Male contraceptives, also known as male birth control, are methods of preventing

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

by interrupting the function of sperm. The main forms of male

contraception Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth control only be ...

available today are

condom A condom is a sheath-shaped Barrier contraception, barrier device used during sexual intercourse to reduce the probability of pregnancy or a Sexually transmitted disease, sexually transmitted infection (STI). There are both external condo ...

vasectomy Vasectomy is an elective surgical procedure that results in male sterilization, often as a means of permanent contraception. During the procedure, the male vasa deferentia are cut and tied or sealed so as to prevent sperm from entering into ...

, and withdrawal, which together represented 20% of global contraceptive use in 2019. New forms of male contraception are in clinical and preclinical stages of

research and development Research and development (R&D or R+D), known in some countries as OKB, experiment and design, is the set of innovative activities undertaken by corporations or governments in developing new services or products. R&D constitutes the first stage ...

, but as of 2025, none have reached regulatory approval for widespread use. They could be available before

2030 Predicted and scheduled events * January 1 – 1934 in literature, Books, 1934 in film, films and other works published in 1934 will enter the public domain. * February 1 – February 17 – The 2030 Winter Olympics is scheduled to be held ...

, assuming smooth development and

clinical trials Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...

. These new methods include topical creams, daily pills, injections, long-acting implants, and external devices, and these products have both hormonal and non-hormonal mechanisms of action. Some of these new contraceptives could even be

unisex Unisex is an adjective indicating something is not sex-specific, i.e. is suitable for any type of sex. The term can also mean gender-blindness or gender neutrality. The term 'unisex' was coined in the 1960s and was used fairly informally. The co ...

, or usable by any person, because they could theoretically incapacitate mature sperm in the man's body before

ejaculation Ejaculation is the discharge of semen (the ''ejaculate''; normally containing sperm) from the penis through the urethra. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. ...

, or incapacitate sperm in the body of a woman after

insemination Insemination is the introduction of sperm (in semen) into a female or hermaphrodite's reproductive system in order to fertilize the ovum through sexual reproduction. The sperm enters into the uterus of a mammal or the oviduct of an oviparous (eg ...

Background

In the 21st century, surveys indicated that around half of men in countries across the world have been interested in using a variety of novel contraceptive methods, and men in clinical trials for male contraceptives have reported high levels of satisfaction with the products. Women worldwide have also shown a high level of interest in new male contraceptives, and though both male and female partners could use their own contraceptives simultaneously, women in long-term relationships have indicated a high degree of trust in their male partner's ability to successfully manage contraceptive use. A modelling study from 2018 suggested that even partial adoption of new male contraceptives would significantly reduce

unintended pregnancy Unintended pregnancies are pregnancies that are mistimed or unwanted at the time of conception, also known as unplanned pregnancies. Sexual activity without the use of effective contraception through choice or coercion is the predominant caus ...

rates around the globe, which remain at nearly 50%, even in developed countries where women have access to modern contraceptives. Unintended pregnancies are associated with negative socioeconomic, educational, and health outcomes for women, men, and the resulting children (especially in historically marginalized communities), and 60% of unintended pregnancies end in

abortion Abortion is the early termination of a pregnancy by removal or expulsion of an embryo or fetus. Abortions that occur without intervention are known as miscarriages or "spontaneous abortions", and occur in roughly 30–40% of all pregnan ...

s, many of which are unsafe and can lead to women's harm or death. Therefore, the development of new male contraceptives has the potential to improve racial, economic, and gender equality across the world, advance reproductive justice and reproductive autonomy for all people, and save lives.

Available methods

Vasectomy

Vasectomy is surgical procedure for permanent male sterilization usually performed in a physician's office in an outpatient procedure. During the procedure, the vasa deferentia of a patient are severed, and then tied or sealed to prevent sperm from being released during ejaculation. Vasectomy is an effective procedure, with less than 0.15% of partners becoming pregnant within the first 12 months after the procedure. Vasectomy is also a widely reliable and safe method of contraception, and complications are both rare and minor. Vasectomies can be reversed, though rates of successful reversal decline as the time since vasectomy increases, and the procedure is technically difficult and often costly.

Condoms

A condom is a barrier device made of

latex Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latices are found in nature, but synthetic latices are common as well. In nature, latex is found as a wikt:milky, milky fluid, which is present in 10% of all floweri ...

or thin plastic film that is rolled onto an erect

penis A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate. The term ''pen ...

before intercourse and retains ejaculated

semen Semen, also known as seminal fluid, is a bodily fluid that contains spermatozoon, spermatozoa which is secreted by the male gonads (sexual glands) and other sexual organs of male or hermaphrodite, hermaphroditic animals. In humans and placen ...

, thereby preventing pregnancy. Condoms are less effective at preventing pregnancy than vasectomy or modern methods of female contraception, with a real-world failure rate of 13%. However, condoms have the advantage of providing protection against some

sexually transmitted infection A sexually transmitted infection (STI), also referred to as a sexually transmitted disease (STD) and the older term venereal disease (VD), is an infection that is Transmission (medicine), spread by Human sexual activity, sexual activity, e ...

s such as

HIV/AIDS The HIV, human immunodeficiency virus (HIV) is a retrovirus that attacks the immune system. Without treatment, it can lead to a spectrum of conditions including acquired immunodeficiency syndrome (AIDS). It is a Preventive healthcare, pr ...

. Condoms may be combined with other forms of contraception (such as

spermicide Spermicide is a contraceptive substance that destroys spermatozoon, sperm, inserted vaginally prior to Sexual intercourse, intercourse to prevent pregnancy. As a contraceptive, spermicide may be used alone. However, the pregnancy rate experienc ...

) for greater protection.

Withdrawal

The withdrawal method, also known as ''coitus interruptus'' or pulling out, is a behavior that involves halting penile-vaginal intercourse to remove the penis out and away from the

vagina In mammals and other animals, the vagina (: vaginas or vaginae) is the elastic, muscular sex organ, reproductive organ of the female genital tract. In humans, it extends from the vulval vestibule to the cervix (neck of the uterus). The #Vag ...

prior to ejaculation. Withdrawal is considered a less-effective contraceptive method, with typical-use failure rates around 20%. However, it requires no equipment or medical procedures.

Research into new methods

Researchers have been working to generate novel male contraceptives with diverse mechanisms of action and possible delivery methods, including long-acting reversible contraceptives (LARCs), daily transdermal gels, daily and on-demand oral pills, monthly injectables, and implants. Efforts to develop male contraceptives have been ongoing for many decades, but progress has been slowed by a lack of funding and industry involvement. As of 2024, most funding for male contraceptive research is derived from government or philanthropic sources. Novel male contraceptives could work by blocking various steps of the sperm development process, blocking sperm release, or interfering with any of the sperm functions necessary to reach and fertilize an egg in the female reproductive tract. Advantages and disadvantages of each of these approaches will be discussed below, along with relevant examples of products in development.

Methods that block or interfere with sperm production

These methods work by preventing the testes from producing sperm, or interfering with sperm production in a way that leads to the production of nonfunctional sperm. This approach can be accomplished by either

hormonal A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physiology and behavior. Hormones a ...

or nonhormonal small-molecule drugs, or potentially by thermal methods. The effectiveness of contraceptives in this group can be easily assessed microscopically, by measuring sperm count or abnormalities in sperm shape, but because

spermatogenesis Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testicle. This process starts with the Mitosis, mitotic division of the stem cells located close to the basement membrane of ...

takes approximately 70 days to complete, these methods are likely to require approximately three months of use before they become effective, and approaches that halt sperm production at an early stage of the process may result in reduced testicular size. Methods have been suggested in the 1980s.

Hormonal male contraceptives

Hormonal contraceptives for men work similarly to hormonal female methods, using

steroid A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes t ...

s to interrupt the hypothalamic-pituitary-gonadal axis and thereby block sperm production. Administering external

androgen An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...

s and

progestogen Progestogens, also sometimes written progestins, progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestoge ...

s suppresses secretion of the gonadotropins LH and FSH, which impairs

testosterone Testosterone is the primary male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting se ...

production and sperm generation in the testes, leading to reduced sperm counts in ejaculates within 4–12 weeks of use. However, since the contraceptives contain testosterone or related androgens, the levels of androgens in the blood remain relatively constant, thereby limiting side effects and maintaining masculine

secondary sex characteristic A secondary sex characteristic is a physical characteristic of an organism that is related to or derived from its sex, but not directly part of its reproductive system. In humans, these characteristics typically start to appear during pubert ...

s like muscle mass and hair growth. Multiple methods of male hormonal contraception have been tested in

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...

s since the 1990s, and although one trial was halted early, leading to a large amount of press attention, most hormonal male contraceptives have been found to be effective, reversible, and well-tolerated.

= In clinical trials

= , the following hormonal male contraceptive products are in clinical trials: *NES/T ( Nesterone/Testosterone gel) is a transdermal gel that users apply to the upper arms and shoulders once daily. Developed as a collaboration between the NICHD and

Population Council The Population Council is an international, nonprofit, non-governmental organization. The Council conducts research in biomedicine, social science, and public health and helps build research capacities in developing countries. One-third of its re ...

, NES/T is in a phase II clinical trial, where it is being evaluated for safety and efficacy, with healthy couples relying on it as their only means of birth control. * DMAU (Dimethandrolone undecanoate) is a steroid-based contraceptive molecule with both

ic and progestational activities, which allows it to be used as a single agent. DMAU has been tested in clinical trials in both oral and injectable forms. * 11β-MNTDC is another dual-function molecule (progestogenic androgen) in clinical development as an oral contraceptive for men. Some anabolic steroids may exhibit suppressive effects on spermatogenesis, but none are being investigated for use as a male contraceptive.

Non-hormonal male contraceptives

Non-hormonal contraceptives for men are a diverse group of molecules that act by inhibiting any of the many

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

s involved in sperm production, release, or function. Because sperm cells are highly specialized, they express many proteins that are rare in the rest of the human body. This suggests the possibility that non-hormonal contraceptives that specifically block these sperm proteins could have fewer side effects than hormonal contraceptives, since sex steroid receptors are found in tissues throughout the body. Non-hormonal contraceptives can work by blocking spermatogenesis, sperm release, or mature sperm function, resulting in products with a wide variety of usage patterns, from slow onset to on-demand usage. Contraceptives targeting mature sperm functions could even be taken by both sperm-producing and egg producing people. Challenges of non-hormonal contraceptive development include

bioavailability In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. H ...

and delivery past the blood-testis barrier.

= In clinical trials

= , the following non-hormonal male contraceptive product is in clinical trials: * YCT529, a

retinoic acid receptor The retinoic acid receptor (RAR) is a type of nuclear receptor which can also act as a ligand-activated transcription factor that is activated by both all-trans retinoic acid and 9-cis retinoic acid, retinoid active derivatives of Vitamin A. ...

antagonist An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.Phase 1 clinical trial in 2023 organized by the US startup YourChoice Pharmaceuticals. The clinical test on humans is done by the UK company Quotient Sciences. It was originally planned in 2022 instead of 2023, with an expected marketing date 5 years later.

= In preclinical development

= , the following non-hormonal male contraceptive products are in

preclinical development In drug development, preclinical development (also termed preclinical studies or nonclinical studies) is a stage of research that begins before clinical trials (testing in humans) and during which important feasibility, iterative testing and dr ...

: * Triptonide, a derivative of '' Tripterygium wilfordii'', a plant used in

traditional Chinese medicine Traditional Chinese medicine (TCM) is an alternative medicine, alternative medical practice drawn from traditional medicine in China. A large share of its claims are pseudoscientific, with the majority of treatments having no robust evidence ...

, has been shown to safely, effectively, and reversibly block sperm production in laboratory mice and monkeys, though the mechanism of action requires more clarification. * BRDT inhibitors such as JQ1 have been shown to produce reversible sterility in male mice by blocking

chromatin remodeling Chromatin remodeling is the dynamic modification of chromatin architecture to allow access of condensed genomic DNA to the regulatory transcription machinery proteins, and thereby control gene expression. Such remodeling is principally carried out ...

, and efforts to develop and evaluate new small-molecule inhibitors with improved

pharmacokinetic Pharmacokinetics (from Ancient Greek ''pharmakon'' "drug" and ''kinetikos'' "moving, putting in motion"; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to describing how the body affects a specific subs ...

properties are ongoing. *Several testis-specific

kinase In biochemistry, a kinase () is an enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates. This process is known as phosphorylation, where the high-energy ATP molecule don ...

s have been linked to male infertility in mice and/or humans, and inhibitors of several of these kinases, such as the testis-specific serine kinases and

Cyclin-dependent kinase 2 Cyclin-dependent kinase 2, also known as cell division protein kinase 2, or Cdk2, is an enzyme that in humans is encoded by the ''CDK2'' gene. The protein encoded by this gene is a member of the cyclin-dependent kinase family of Ser/Thr protein ...

are in

medicinal chemistry Medicinal or pharmaceutical chemistry is a scientific discipline at the intersection of chemistry and pharmacy involved with drug design, designing and developing pharmaceutical medication, drugs. Medicinal chemistry involves the identification, ...

development. *The

retinoic acid Retinoic acid (simplified nomenclature for all-''trans''-retinoic acid) is a metabolite of vitamin A1 (all-''trans''-retinol) that is required for embryonic development, male fertility, regulation of bone growth and immune function. All-''trans ...

signalling pathway has been known since the late 1950s to be necessary for spermatogenesis in rodents and humans, and various attempts have been made to develop male contraceptives that work by blocking different enzymes in this pathway. As of 2024, efforts are underway to develop inhibitors of ALDH1A2, Retinoic acid receptor alpha, and SMRT. New male contraceptive methods could be available before

, assuming smooth development and

= Thermal male contraception

= Prolonged testicular heating had been shown to reduce sperm counts in 1941, considered as a method of birth control after 1968 and in the 1980s No modern clinical trials have demonstrated the safety, contraceptive effectiveness, or reversibility of this approach. Various devices are in early preclinical stages of development, and as of 2017 some approaches have been used by men through self-experimentation. As of 2015, the mechanism by which heating disrupts spermatogenesis was still not fully understood. There have been theoretical concerns that prolonged heating could increase the risk of

testicular cancer Testicular cancer is cancer that develops in the testicles, a part of the male reproductive system. Symptoms may include a lump in the testicle or swelling or pain in the scrotum. Treatment may result in infertility. Risk factors include an c ...

since the inborn birth defect of cryptorchidism carries a risk of testicular cancer or that heating could damage sperm DNA, resulting in harm to potential offspring.

Methods that block sperm release

These approaches work by either physically or chemically preventing the emission of sperm during ejaculation, and are likely to be effective on-demand.

Non-hormonal pharmaceutical methods in preclinical and clinical development

α1-adrenoceptor antagonists and P2X1 antagonists have been shown to inhibit

smooth muscle Smooth muscle is one of the three major types of vertebrate muscle tissue, the others being skeletal and cardiac muscle. It can also be found in invertebrates and is controlled by the autonomic nervous system. It is non- striated, so-called bec ...

contractions in the

vas deferens The vas deferens (: vasa deferentia), ductus deferens (: ductūs deferentes), or sperm duct is part of the male reproductive system of many vertebrates. In mammals, spermatozoa are produced in the seminiferous tubules and flow into the epididyma ...

during ejaculation, and therefore prevent the release of semen and sperm while maintaining the sensation of

orgasm Orgasm (from Greek , ; "excitement, swelling"), sexual climax, or simply climax, is the sudden release of accumulated sexual excitement during the sexual response cycle, characterized by intense sexual pleasure resulting in rhythmic, involu ...

. Various molecules in these categories are under consideration as possible on-demand male contraceptives. * Silodosin and Tamsulosin are α1-adrenoceptor antagonists approved to treat

Benign Prostatic Hyperplasia Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, urinary retention, inability t ...

, and their ejaculation-blocking effects have been evaluated in humans. A patent for their use as contraceptives was filed in 2023 and approved in 2024. Other α1-adrenoceptor antagonists such as phenoxybenzamine have shown inhibition of ejaculation as a side effect, and have been investigated as potential male contraceptives, but work on these molecules is not active as of 2024. * Novel small molecule P2X1 antagonists are also in early screening and development as potential ejaculation blockers as of 2024.

Vas-occlusive contraception

Vas-occlusive contraception is a form of male

that blocks

sperm Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ...

transport in the

, the tubes that carry sperm from the

epididymis The epididymis (; : epididymides or ) is an elongated tubular genital organ attached to the posterior side of each one of the two male reproductive glands, the testicles. It is a single, narrow, tightly coiled tube in adult humans, in length; ...

to the ejaculatory ducts. Vas-occlusive contraception provides a contraceptive effect through physical blockage of the

, the duct connecting the

to the

urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated ...

. While a

excises, or removes, a piece of each vas deferens and occludes the remaining open ends of the duct, vas-occlusive methods aim to block the duct while leaving it intact. Vas-occlusive methods generally aim to create long-acting reversible options, through a second procedure that removes the blockage. However, full reversibility remains questionable, since animal and human studies have shown sperm abnormalities, incomplete recovery of sperm parameters, and the development of fertility-impairing

antibodies An antibody (Ab) or immunoglobulin (Ig) is a large, Y-shaped protein belonging to the immunoglobulin superfamily which is used by the immune system to identify and neutralize antigens such as bacteria and viruses, including those that caus ...

against one's own sperm after blockage removal.

= In clinical trials

= , the following vas-occlusive male contraceptive products are in clinical trials: * RISUG is an injectable male contraceptive vas-occlusive gel that has been in development in India since the 1970s, and has shown high effectiveness at pregnancy prevention in multiple clinical trials through Phase III in India, though the results of the largest phase III study were published in a questionably peer-reviewed

predatory journal Predatory publishing, also write-only publishing or deceptive publishing, is an exploitative academic publishing business model, where the journal or publisher prioritizes self-interest at the expense of scholarship. It is characterized by misle ...

. RISUG is proposed to be reversed through a second injection that dissolves the polymer, but as of 2024, reversibility and return to fertility after removal of RISUG have not been shown in humans. As of 2022, RISUG was awaiting approval from the Drug Controller General of India for mass production. * ADAM is a

hydrogel A hydrogel is a Phase (matter), biphasic material, a mixture of Porosity, porous and Permeation, permeable solids and at least 10% of water or other interstitial fluid. The solid phase is a water Solubility, insoluble three dimensional network ...

-based male contraceptive implant in early clinical development by Contraline, Inc. The implant is administered to a user in a procedure similar to a no-scalpel vasectomy, and is proposed to provide protection from pregnancy for approximately two years, after which the hydrogel degrades, thereby restoring fertility.

= In preclinical development

= , the following vas-occlusive male contraceptive products are in preclinical development: * Plan A, formerly known as Vasalgel, is an adaptation of the polymer used in RISUG, which as of 2024 is in preclinical development in the United States by NEXT life sciences. * Other methods for vas occlusion have been proposed, though these methods are largely in very early development.

Barrier methods

Research into new, more acceptable designs of condoms is ongoing.

Methods that block functions of mature sperm

These approaches work by blocking functions that mature sperm need in order to reach and fertilize an egg in the female reproductive tract, such as

motility Motility is the ability of an organism to move independently using metabolism, metabolic energy. This biological concept encompasses movement at various levels, from whole organisms to cells and subcellular components. Motility is observed in ...

, capacitation, semen liquification, or

fertilization Fertilisation or fertilization (see American and British English spelling differences#-ise, -ize (-isation, -ization), spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give ...

. Drugs or devices that target mature sperm are likely to be effective on-demand (taken just before intercourse), and could even be delivered either in sperm-producing or egg-producing bodies, leading to unisex contraceptives.

In preclinical development

, the following non-hormonal male contraceptive approaches are in preclinical or early development: *Short-term inhibition of soluble adenylyl cyclase has been demonstrated to temporarily impair

sperm motility Sperm motility describes the ability of sperm to move properly through the female reproductive tract (internal fertilization) or through water ( external fertilization) to reach the egg. Sperm motility can also be thought of as the ''quality'', wh ...

and capacitation, and thereby block fertility in mice.

Medicinal chemistry Medicinal or pharmaceutical chemistry is a scientific discipline at the intersection of chemistry and pharmacy involved with drug design, designing and developing pharmaceutical medication, drugs. Medicinal chemistry involves the identification, ...

efforts are underway to develop molecules that could be used as on-demand contraceptives. *EP055 is a non-hormonal contraceptive molecule in development that works by targeting the sperm protein Eppin and blocking the initiation of sperm motility after ejaculation. *Inhibitors of various sperm

ion channel Ion channels are pore-forming membrane proteins that allow ions to pass through the channel pore. Their functions include establishing a resting membrane potential, shaping action potentials and other electrical signals by Gating (electrophysiol ...

s/ transporters such as CatSper, sNHE, Slo3, and NKAα4, are in development. These inhibitors generally act to block sperm motility and/or capacitation, and have the potential to be administered either systemically in males or through vaginal delivery in females. *Blocking

prostate The prostate is an male accessory gland, accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found in all male mammals. It differs between species anatomically, chemica ...

-derived serine proteases, such as PSA, is under consideration as a way to prevent semen liquifaction and therefore trap sperm in the ejaculate and prevent it from crossing through the

cervix The cervix (: cervices) or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the time ...

towards the egg. *Sperm-specific metabolic enzymes needed to power motility, such as Lactate Dehydrogenase C, GAPDHS, are also being evaluated as inhibition targets for developing male contraceptives.

Acceptability

Although some people question whether men would be interested in managing their own contraceptives or whether women would trust their male partners to do so successfully, studies consistently show that men around the world have significant levels of interest in novel forms of male contraception and that women in committed relationships would generally trust their male partners to manage the contraceptive burden in the relationship. Additionally, males participating in various contraceptive clinical trials have reported high satisfaction with the products they were using.

Among men

Studies on potential uptake indicate that in most countries, more than half of men surveyed would be willing to use a new method of male contraception. Interestingly, some of the highest rates were reported in low-income countries like Nigeria and Bangladesh where 76% of men surveyed indicated that they would be willing to use a new method within the first 12 months that it is available. This is particularly compelling, since it has been estimated that a mere 10% uptake of new male contraceptive methods could avert nearly 40% of unintended pregnancies in Nigeria. Across the world, many young and middle-aged men especially want the ability to control their own fertility, and are not well-served by existing family planning programs. Although a phase II trial for an injectable male contraceptive was halted in 2011 by an independent data safety monitoring board due likely to rare adverse effects experienced by some participants, leading many popular articles to suggest men could not tolerate side effects similar to those that many women endure on hormonal birth control, in reality more than 80% of the study's male participants stated at the end of the trial that they were satisfied with the contraceptive injection, and would be willing to use the method if it were available. Subsequent hormonal male contraceptive clinical trials have progressed successfully, showing high levels of efficacy and acceptability among the participants.

Among women

It is sometimes assumed that women won't trust men to take contraceptives, since women would bear the consequences of a male partner's missed dose or misuse. Of course, male contraceptive options would not have to replace female contraceptives, and in casual sexual encounters both partners may prefer to independently control their own contraceptive methods. On the other hand, some long-term couples might want only one partner to bear the contraceptive burden. Indeed, there is evidence that a large proportion of women in relationships in many countries around the world would trust their partners to take a potential male method, and many women want more male partner involvement in their own reproductive health services. Further, current contraceptive use data show that more than a quarter of women worldwide already rely on male-controlled methods for contraception (such as condoms and vasectomy), and this figure could grow as more male contraceptive methods become available.

Potential benefits

On unintended pregnancy rates

Despite the fact that modern female pharmaceutical contraception has been on the market since the 1960s, 40-50% of pregnancies are still unintended worldwide, leading to an approximate total of 121 million unintended pregnancies annually. Importantly, most studies on unintended pregnancies only measure women's intentions about the pregnancy, and so pregnancies that were unintended by men are understudied and may be under-reported. Unintended pregnancies have been shown to be linked with a wide variety of negative outcomes on mental and physical health, as well as educational and socioeconomic attainment in both parents and the children born of unintended pregnancies. Surprisingly, although the rate of unintended pregnancies (per 1000 women of childbearing age) is higher in

developing countries A developing country is a sovereign state with a less-developed Secondary sector of the economy, industrial base and a lower Human Development Index (HDI) relative to developed countries. However, this definition is not universally agreed upon. ...

, the percentage of pregnancies that are unintended is actually higher in

developed countries A developed country, or advanced country, is a sovereign state that has a high quality of life, developed economy, and advanced technological infrastructure relative to other less industrialized nations. Most commonly, the criteria for eval ...

, since a lower proportion of women in developed countries are intending to conceive at any given time. Research indicates that unmet need for modern contraception is the cause of 84% of unintended pregnancies in developing countries. In the United States, which has a higher unintended pregnancy rate than many other developed nations, one important reason that women cite for nonuse of contraceptives is concerns about the side effects of existing products. Taken together, these statistics suggests that the current suite of contraceptives is insufficient to meet the fertility planning needs of people across the world, and therefore the introduction of new male contraceptives is likely to decrease the stubbornly high global rates of unintended pregnancy. International market research indicates that 49% of men in the United states and 76% of men in Nigeria would try a novel male contraceptive within the first year of its existence. Independent modelling predicts that even if real-world usage is only 10% as high as the market research suggests, the introduction of a male contraceptive would avert roughly 200,000 unintended pregnancies per year in the USA and Nigeria each.

For men

Fathers with unintended births report lower proportions of happiness than in fathers with intentional births and unintended fatherhood for men in their early 30s is associated with a significant increase in depressive symptoms. In addition, men in insecure financial situations are more likely to report a recent unintended pregnancy, and supporting and raising a child brings significant costs that can exacerbate financial insecurity. More broadly, access to effective and reliable contraception would advance men's ability to "maintain personal bodily autonomy, have children, not have children, and parent the children we have in safe and sustainable communities" in accordance with the principles of Reproductive Justice.

For women and gender equity

Family planning has been found to be associated with overall well-being and is one of the most efficient tools for women's empowerment. Positive outcomes of effective birth control include improvements in women's health, self-agency, education, labor force participation, financial stability, as well as decreases in pregnancy-related deaths, and these positive social and health impacts may be further realized by the addition of novel male and unisex methods. New male contraceptive options would not come at the expense of women’s reproductive autonomy, since women would still be able to take advantage of all of the contraceptive methods available to them, choose to have both partners use their own contraceptive methods at the same time, or rely solely on their male partners’ form of contraception. Interventions encouraging male engagement in couples' reproductive health and decisionmaking have shown positive outcomes related to promoting more equitable gender norms in the context of family planning, and increased joint decision making in couples. It is reasonable to assume from these data that increasing male involvement as contraceptive users will further improve gender equity.

For transgender, nonbinary, and intersex people

While this article has used the term "male" contraception for clarity, these contraceptives are most accurately described as "sperm-targeting" contraceptives, since they would work effectively in any body that produces sperm, regardless of that person's gender identity or external genitalia. Importantly, contraceptives that block functions of mature sperm could be delivered in a

manner, incapacitating sperm before ejaculation in sperm-producing people, or after sperm arrives in the body of egg-producing people.

Transgender A transgender (often shortened to trans) person has a gender identity different from that typically associated with the sex they were sex assignment, assigned at birth. The opposite of ''transgender'' is ''cisgender'', which describes perso ...

, nonbinary, and

intersex Intersex people are those born with any of several sex characteristics, including chromosome patterns, gonads, or genitals that, according to the Office of the United Nations High Commissioner for Human Rights, "do not fit typical binar ...

people are underserved by current contraceptive options. For example, many trans men can become pregnant (both intentionally and unintentionally), but may prefer not to use

estrogen Estrogen (also spelled oestrogen in British English; see spelling differences) is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three ...

- or

progestin A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural female sex hormone progesterone in the body. A progestin is a '' synthetic'' progestogen. ...

-containing hormonal birth control (both because of the social classification of these hormones as "female sex hormones" and because of a fear they will interfere with masculinizing hormone therapy, although the American College of Obstetricians and Gynecologists states that these hormonal contraceptives have little effect on masculinization.) Trans women who have not had gender-affirming genital surgery may have similar unmet contraceptive needs as those of

cisgender The word ''cisgender'' (often shortened to ''cis''; sometimes ''cissexual'') describes a person whose gender identity corresponds to their sex assigned at birth, i.e., someone who is not ''transgender''. The prefix '' cis-'' is Latin and ...

men, since gender-affirming hormonal therapy is not effective contraception. Nonbinary and intersex people may be less likely to use current methods of birth control, since they are popularly categorized by the labels "male" and "female", which may not match an individual's gender identity or may invoke feelings of

gender dysphoria Gender dysphoria (GD) is the distress a person experiences due to inconsistency between their gender identitytheir personal sense of their own genderand their sex assigned at birth. The term replaced the previous diagnostic label of gender i ...

. This dynamic may contribute to the higher rates of unintended pregnancies seen in the

LGBTQ+ LGBTQ people are individuals who are lesbian, gay, bisexual, transgender, queer, or questioning. Many variants of the initialism are used; LGBTQIA+ people incorporates intersex, asexual, aromantic, agender, and other individuals. The group i ...

community as compared to

heterosexual Heterosexuality is romantic attraction, sexual attraction, or sexual behavior between people of the opposite sex or gender. As a sexual orientation, heterosexuality is "an enduring pattern of emotional, romantic, and/or sexual attractions ...

peers, which could in theory be ameliorated by the introduction of

contraceptives.

For child welfare

Novel male contraceptive options are predicted to reduce the incidence unintended pregnancies, and being the product of an intended rather than unintended pregnancy has been shown to correlate with improved health and wellbeing outcomes in children. Additionally, reduced family size correlates with improved educational outcomes, and children born after the introduction of family planning programs in the USA experienced a reduction in poverty rates, both in childhood and adulthood.

For racial and socioeconomic equality

Unintended pregnancies rates increase as income decreases, both between countries and between socioeconomic and racial groups within a given country. Women of color, especially Black women, in the United States and other developed countries have dramatically higher rates of death during and after birth and worse maternal health outcomes, due in part to systemic discrimination. Since unintended pregnancies can have negative effects on an individual's physical and mental health, educational attainment, and economic prospects, these higher unintended pregnancy rates likely contribute to the persistent socioeconomic gaps within and between societies. It's therefore possible that the introduction of new male contraceptives would not only mitigate gender inequities, as discussed above, but racial and income inequities as well, by providing more ways for individuals to avoid unintended pregnancies.

For national economies

In addition to the personal financial savings of avoiding unintended pregnancy mentioned above, on a societal level, contraceptives are a public health intervention with a high return on investment: for every dollar the United States government spends on family planning programs, it saves $7.09, for a total of over $13 billion per year. Unintended pregnancies in the United States are estimated to cause $4.5 billion in direct medical costs. New male contraceptives are likely to prevent some unintended pregnancies and therefore reduce these costs.

On abortion rates

61% of unintended pregnancies end in

, whereas only 20% of all pregnancies end in abortion. Interestingly, unintended pregnancy rates are higher in countries where abortion is illegal than those where abortion is legal, yet the incidence of abortion is similar between these groups of countries. Illegal abortions are more likely to be unsafe, and there are an estimated 25 million unsafe abortions globally each year, leading to 50,000 - 70,000 yearly deaths and 5 million people with long-term health consequences. Importantly, increases in the prevalence and uptake of modern contraceptives have been shown to decrease unintended pregnancy and abortion rates when fertility rates are constant. This suggests that the introduction of new forms of male contraception could prevent a significant number of abortions, save lives, and avoid unnecessary suffering.

History

Early history

A variety of plant extracts have been used throughout history in attempts to prevent pregnancy, though most were used by women, and the efficacy and safety of these methods is questionable.

Condom A condom is a sheath-shaped Barrier contraception, barrier device used during sexual intercourse to reduce the probability of pregnancy or a Sexually transmitted disease, sexually transmitted infection (STI). There are both external condo ...

s made of animal organs or fabric have been in documented use since at least the 16th century, and various types of penile coverings have been depicted and referenced in materials from cultures around the world as early as 3000 BCE, though it is not always clear that these coverings were used for birth control or protection from sexually transmitted infections. The 1800s saw the development of thick reusable rubber condoms, and thinner disposable latex rubber condoms entered production in the 1920s.

Vasectomy Vasectomy is an elective surgical procedure that results in male sterilization, often as a means of permanent contraception. During the procedure, the male vasa deferentia are cut and tied or sealed so as to prevent sperm from entering into ...

was first performed in humans in the late 1800s, but not initially as a method of voluntary birth control. Instead, it was first used as an attempted treatment (later proved to be ineffective) for enlarged prostates, and within a few years, one-sided vasectomy became popular as a supposed method of sexual rejuvenation in older men. Although this rejuvenation treatment was ineffective

pseudoscience Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable cl ...

and any perceived effects were likely due only to the

placebo effect A placebo ( ) can be roughly defined as a sham medical treatment. Common placebos include inert tablets (like sugar pills), inert injections (like saline), sham surgery, and other procedures. Placebos are used in randomized clinical trials ...

, many prominent men, such as Sigmund Freud and W.B. Yeats, sought out the procedure. In the early 1900s, the use of vasectomy took a darker turn, and it became widely promoted and practiced as a means of eugenic involuntary sterilization. It was not until the 1950s that vasectomy became widely used as a method for voluntary sterilization and family planning. Since then, vasectomy has undergone extensive technical improvements and innovations, such that it is no longer a single procedure, but a family of related procedures.

Modern history

In the 1990s, and into the early 2000s, major pharmaceutical companies

Organon The ''Organon'' (, meaning "instrument, tool, organ") is the standard collection of Aristotle's six works on logical analysis and dialectic. The name ''Organon'' was given by Aristotle's followers, the Peripatetics, who maintained against the ...

Wyeth Wyeth Pharmaceuticals Inc. was a pharmaceutical company until it was purchased by Pfizer in 2009. The company was founded in Philadelphia, Pennsylvania, in 1860 as John Wyeth and Brother. Its headquarters moved to Collegeville, Pennsylvania, a ...

, and Schering were pursuing preclinical and clinical development of various male contraceptive products, but in 2006, all three companies ceased development of these products within a short time of each other, for reasons that have not been publicly released. In 2013, the Male Contraceptive Initiative was founded with the goal of funding and supporting the development of new male contraceptives. In 2020, Dr. Polina Lishko was awarded the MacArthur "Genius" Fellowship for her contributions to the understanding of sperm physiology, with the award specifically noting her work on "opening up new avenues in ... the development of male-specific or unisex contraceptives."

Past research efforts

Many researchers have attempted to develop male contraceptive products over the last hundred years. A selection of these efforts (that are no longer in development as of 2024) are listed below. * Hormonal ** Trestolone (MENT) was investigated as a contraceptive implant in the 1990s and early 2000s by the

, but this molecule was never approved for contraceptive use. ** An injectable male contraceptive consisting of

Testosterone undecanoate Testosterone undecanoate, sold under the brand name Nebido among others, is an androgen and anabolic steroid (AAS) medication that is used mainly in the treatment of low testosterone levels in men, It is taken by mouth or given by injection ...

and

Norethisterone enanthate Norethisterone enanthate (NETE), also known as norethindrone enanthate, is a form of hormonal birth control which is used to prevent pregnancy in women. It is used both as a form of progestogen-only injectable birth control and in combined inje ...

reached Phase II clinical trials in 2008. The injection was administered every 8 weeks, and it effectively and reversibly suppressed sperm production in at least 95% of the participants. However, in 2011 the trial was halted early on the recommendation of a

World Health Organization The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Gen ...

Research Project Review Panel, based on their evaluation of

adverse event In pharmaceuticals, an adverse event (AE) is any unexpected or harmful medical occurrence that happens to a patient during medical treatment or a clinical trial. Unlike direct side effects, an adverse event does not necessarily mean the medicati ...

s, specifically noting "mood changes, depression, pain at the injection site, and increased libido". This decision generated significant controversy amongst scientists and in public media. * Non-Hormonal ** WIN 18446 is a molecule initially developed by a pharmaceutical company called

Sterling Drug Sterling Drug was an American based global pharmaceutical company. It was also known as Sterling Winthrop, Inc., after the merger with Winthrop-Stearns Inc. which itself resulted from the merger of Winthrop Chemical Company Inc. and Frederick Ste ...

that was shown to produce reversible infertility in rats. In the late 1950s, it was tested in male prisoners at the Oregon State Penitentiary, and while it showed effective and reversible suppression of sperm production with limited adverse effects, if men drank alcohol while taking WIN 18446, they experienced a severe Disulfiram-alcohol reaction, including nausea, vomiting, and heart palpitations, and so the molecule was not developed further at that time. However, research on this class of compounds was renewed in 2006 by a team at

University of Washington The University of Washington (UW and informally U-Dub or U Dub) is a public research university in Seattle, Washington, United States. Founded in 1861, the University of Washington is one of the oldest universities on the West Coast of the Uni ...

, who uncovered the mechanism of action for the contraceptive effect and the alcohol reaction (inhibition of Aldehyde dehydrogenase (ALDH) enzymes), and are attempting to produce molecules that selectively inhibit the sperm-specific isoform of the enzyme ( ALDH1A2). **

Gossypol Gossypol () is a natural phenol derived from the cotton plant (genus ''Gossypium''). Gossypol is a phenolic aldehyde that permeates cells and acts as an inhibitor for several dehydrogenase enzymes. It is a yellow pigment. The structure exhibits ...

, an extract of cotton, has been studied as a male contraceptive pill, and was given to thousands of men in China in the 1970s. It successfully decreased sperm production, leading to infertility without significant adverse effects, but this effect was permanent in a substantial percentage of the users, and so it was not pursued for widespread approval. However, synthetic derivatives of gossypol that work through a similar mechanism of action, but more selectively target the sperm-specific Lactate Dehydrogenase C enzyme, are still in development as potential male contraceptives. ** Miglustat (Zavesca or NB-DNJ) is a drug approved for treatment of several rare lipid storage disorders. In several genetically-related strains of

laboratory mice The laboratory mouse or lab mouse is a small mammal of the order Rodentia which is bred and used for scientific research or feeders for certain pets. Laboratory animal sources for these mice are usually of the species ''Mus musculus''. They a ...

, it provided effective and fully reversible contraception, but later studies of showed no contraceptive effect in rabbits or humans. ** Various small molecules have been shown to cause infertility in rodents and other species by disrupting the junctions between

Sertoli cells Sertoli cells are a type of sustentacular "nurse" cell found in human testes which contribute to the process of spermatogenesis (the production of sperm) as a structural component of the seminiferous tubules. They are activated by follicle-sti ...

and elongating

spermatids The spermatid is the haploid male gametid that results from division of secondary spermatocytes. As a result of meiosis, each spermatid contains only half of the genetic material present in the original primary spermatocyte. Spermatids are con ...

, leading to premature release of immature, nonfunctional sperm. These fertility-disrupting molecules include derivatives of

lonidamine Lonidamine is a derivative of indazole-3-carboxylic acid, which for a long time, has been known to inhibit aerobic glycolysis in cancer cells. It seems to enhance aerobic glycolysis in normal cells, but suppress glycolysis in cancer cells. This i ...

, such as

Adjudin Adjudin (AF-2364) is a drug which is under development as a potential non-hormonal male contraceptive drug, which acts by blocking the production of sperm in the testes, but without affecting testosterone production. It is an analogue of the che ...

and Gamendazole, and indenopyridine derivatives such as RTI-4587-073(l) (also known as CDB-4022). Toxicity, reversibility, and

challenges limited the development of lonidamide derivatives, though efforts to create more specific delivery vehicles partially ameliorated these problems. A new lonidamide derivative called BHD that showed contraceptive effects in rodents was developed in 2023, but further characterization is needed. Indenopyridine derivatives have not been fully evaluated for effects on fertility and toxicity, and as of 2024, it is unclear if work on these compounds is ongoing. ** In the 20th century, various small molecules such as α-chlorohydrin and 6-chloro-6-deoxy-glucose were shown to cause infertility in rodents, but these molecules also caused unacceptable systemic toxicity, and were not developed further. ** Contraceptive immunization with sperm

antigen In immunology, an antigen (Ag) is a molecule, moiety, foreign particulate matter, or an allergen, such as pollen, that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. ...

s has been found to be partially effective and reversible in male primates. ** Numerous plant extracts and naturally-derived molecules have been preliminarily evaluated for use as male contraceptives or

s. While some of these extracts have become the basis of more specific molecular drug development campaigns mentioned earlier in this article, others require more work to clarify the

active ingredient An active ingredient is any ingredient that provides biologically active or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure or any function of the body of humans or animals. ...

, or further research into

efficacy Efficacy is the ability to perform a task to a satisfactory or expected degree. The word comes from the same roots as '' effectiveness'', and it has often been used synonymously, although in pharmacology a distinction is now often made betwee ...

toxicity Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacteria, bacterium, or plant, as well as the effect o ...

, and reversibility. These molecules face an additional financial challenge in drug development, since unaltered natural products cannot be patented in the United States and many other countries, which reduces the interest of for-profit pharmaceutical companies in these compounds. * Vas-Occlusive ** The following vas-occusive device prototypes were developed in the late 20th and early 21st centuries, but are no longer in development. *** The intra-vas device (IVD) was a rod-shaped device intended to be inserted into the lumen of the

via a small incision. *** The “Shug” was a noninjectable device consisting of 2 silicone plugs with nylon tails to help anchor the plug to the vas deferens, and was inserted via the no-scalpel scrotal puncture method. *** Injectable medical

polyurethane Polyurethane (; often abbreviated PUR and PU) is a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane term ...

was used as a vas-occlusive contraceptive for several hundred thousand men in China in the 1980s.

Notes

References

External links

Prominent funders of male contraceptive research

Male Contraceptive Initiative

National Institute of Child Health and Human Development

Conferences and courses discussing male contraception

Scientific Research

International Congress on Male Contraception

American Society for Andrology Meeting

North American Testis Workshop
*
European Society of Human Reproduction and Embryology Annual Meeting

Society for the Study of Reproduction Annual Meeting

Gordon Research Conference on Fertilization and Activation of Development

Gordon Research Conference on Mammalian Reproduction

NICHD Contraceptive Development Meeting

Frontiers in Reproduction Summer Course

Clinical care, advocacy, and accessibility

International Conference on Family Planning

National Family Planning and Reproduction Health Association Meeting

National Reproductive Health Conference

Society of Family Planning Annual Meeting
{{DEFAULTSORT:Male Contraceptive Birth control Contraception for males Clinical research Medical research Reproduction Human sexuality Women's health Gender equality Women's empowerment Men's health Andrology Urology