Male contraception: history and development

Comparison of Childless and Partnerless Vasectomy Rates Before and After Dobbs v. Jackson Women's Health Organization

The Supreme Court ruling Dobbs v. Jackson Women's Health Organization (June 2022) overturned federal protection of abortion rights, resulting in significant impact on both male and female reproductive rights and health care delivery. We conducted a retrospective review of all patients who underwent vasectomy at a single academic institution between June 2021 and June 2023. Our objective was to compare the rates of childless and partnerless vasectomies 1 year before and after this ruling, as these men may be more susceptible to postprocedural regret. Of total, 631 men (median age = 39 years, range = 20-70) underwent vasectomy consultation. Total vasectomies pre- and post-Dobbs were 304 (48%) versus 327 (52%). Total childless and partnerless vasectomies pre- and post-Dobbs were 44 (42%) versus 61 (58%) and 43 (46%) versus 50 (54%). Vasectomy completion rate was slightly increased post-Dobbs (90% vs. 88%; p = .240). The post-Dobbs cohort had significantly less children (1.8 vs. 2.0; p = .031). Men in the post-Dobbs era were significantly more likely to be commercially insured (72% vs. 64%) and less likely to be uninsured (1% vs. 6%; p = .002). Men who underwent childless vasectomy were significantly more likely to be younger (36.4 vs. 39.8 years; p < .001). There was a significantly greater proportion of Hispanic and Black men in the partnerless cohort compared to the cohort with partners (24% vs. 19% and 9% vs. 2%; p = .002). In conclusion, patients should be counseled on the permanent nature of this procedure, underscoring need for effective and reversible male contraception.

'That just sounds bizarre': factors affecting heterosexual college students' perceptions of new sperm-targeting contraceptives

Contraceptive responsibility has historically fallen on women in the context of heterosexual relationships, often resulting in a perceived burden on their emotional and reproductive health. We conducted in-depth, individual interviews with women and men in college to investigate factors influencing the choices they make regarding contraceptive use and more specifically their perceptions and willingness to try new sperm-targeting contraceptives. Thematic analysis revealed factors at a societal, interpersonal, and individual level affecting participants' perceptions and imagined decisions. Societally, a perceived gendered divide continues to exist placing primary responsibility for contraceptive use on women. Interpersonally, the context of a relationship increased partners' feelings of empathy and willingness to try alternative contraceptive methods; and individually participants remained concerned about their own sexual and reproductive safety. Findings indicate that societal level norms need to be shifted towards the acceptability of sperm-targeting contraceptives or other versions of contraceptives that act on male bodies, in addition to a greater focus on their development. It is proposed that this would help to ease the continued undue burden placed on women for reproductive health.

A brief history and future prospects of contraception

Modern contraception ushered in an era of improved family planning, but more than 60 years after approval of "the pill," product gaps and unmet needs still exist. Nearly 250 million women worldwide who want to delay or avoid pregnancy do so ineffectively or not at all, and the principal mechanism of male contraception, condoms, has not changed in 100 years. As a result, about half of the pregnancies that occur globally each year are unintended. Increasing contraceptive options and uptake will curtail abortions, empower women and men, promote healthy families, and moderate population growth that overtaxes the environment. This Review addresses the history of contraception, shortcomings in contraceptive methods, promising approaches for male and female contraception, and simultaneous protection against unintended pregnancy and sexually transmitted infections.

Identification and validation of Sertoli cell homing peptides as molecular steering for testis targeted drug delivery

The testicle, an organ privileged with immunity because of Blood-Testis Barrier (BTB), poses a major impediment to developing and delivering drugs to the testes. These problems can be prevented by targeting testicular cells using specific ligands, such as homing peptides. This is the first study to demonstrate the successful selection of Sertoli cell homing peptides using a phage display peptide library. The identification of peptides is performed with Sanger sequencing and high-throughput NGS. The Sertoli cell and testis targeting potential of the SCHP1 and SCHP2 was confirmed using confocal microscopy and flow cytometry of the FITC-labelled peptides and in vivo bio-distribution of the corresponding Cy5.5-tagged peptides. Secondary structures were predicted in the setting of different polarity by circular dichroism. The results suggest that SCHP1 and SCHP2 can effectively target Sertoli cells. In vivo bio-distribution in mouse models indicated significantly higher uptake of SCHP1 and SCHP2 by testes compared with the heart, brain, and spleen. SCHP1 and SCHP2 can be adopted as molecular steering for targeted male contraceptive delivery, treatment of testicular cancer, and male infertility. Further development of the peptides into peptidomimetics may increase their stability, and information on the molecular targets of these peptides may reveal their therapeutic potential.

[Vasectomy : Current information]

Vasectomy is considered to be the simplest, most effective and cheapest method of fertility control in men, with a significantly lower risk of morbidity and mortality compared to tubal ligation in women. Patient informed consent is particularly important and should include potential irreversibility, surgical options, anesthesia, possible complications as well as postoperative behavior and the need for re-evaluation. There are different access routes available with conventional and no-scalpel vasectomy as well as different techniques for closing the ends of the vas deferens. To confirm sterility the European Association of Urology (EAU) recommends that an ejaculate analysis should be performed 3 months after the procedure and after approximately 20 ejaculations. Complications are relatively rare, although particularly vasectomy failure due to recanalization has to be considered. Approximately 3-6% of vasectomized men strive for a refertilization, which with experienced surgeons is successful in about 90% of cases.

BET proteins: Investigating BRDT as a potential target for male contraception

While many contraception options are available for women, birth control methods for men are limited to condoms and vasectomy. Past research into male contraceptives has focused on hormonal options but the associated side effects have thus far precluded this method from reaching the market. Non-hormonal male contraceptives and vas occlusion have also been explored, but to date no method has progressed past clinical testing. Recent interest in epigenetic research has unveiled a new potential non-hormonal male contraceptive target: the testis-specific bromodomain BRDT. Potent inhibitors for bromodomain-containing proteins are described in the literature, but a BRDT-specific compound has yet to be designed, prepared and tested. The high similarity between bromodomain proteins of the BET family makes development of selective and specific inhibitors both difficult and necessary. Selective inhibition of BRDT by a small molecule is an exciting new target in the search for a new non-hormonal male contraceptive.

RISUG® as a male contraceptive: journey from bench to bedside

Even after decades of research men still lack reliable and reversible contraceptive methods comparable to female methods of contraception. Traditional methods of male contraception present a high failure rate and also involve high risk both when used for contraception and for protection against sexually transmitted diseases. Various chemical, hormonal, immunological, vas based and herbal methods of contraception have been examined by scientists world over during the past four decades. Among the possible lead approaches, exogenous hormonal contraception, either alone or in combination with progesterone or antiandrogen, is being viewed at low profile because of their insufficiency in inducing uniform suppression of spermatogenesis and steroid related long term complications. As an alternative to vasectomy, among various intravasal devices being examined, RISUG® (Reversible Inhibition of Sperm Under Guidance), a co-polymer of styrene and maleic anhydride offers long term contraception with safety, efficacy and it can be delivered by no-scalpel injection. Thus it is the only male contraceptive procedure currently under Phase- III Clinical Trial. The non-invasive reversal technique, successfully demonstrated in langur monkeys and functional reversal achieved with dimethyl sulphoxide (DMSO) and sodium bicarbonate (NaHCO3) in rats and rabbits with safety at F1 generation (first filial generation) have projected RISUG® as a better alternative to vasectomy. In this narrative review we revisit the long journey of RISUG® beginning with formulation on a bench towards reaching the market as a safe and effective contraceptive method, discussing various milestones and roadblocks of this expedition awaiting the mandatory regulatory clearance from the Government of India. Successful completion of ongoing phase III clinical trials with demonstration of reversal in human volunteers will give an indigenously developed male contraceptive to the world.

N-Butyldeoxygalactonojirimycin Induces Reversible Infertility in Male CD Rats

This study shows for the first time that an iminosugar exerts anti-spermiogenic effect, inducing reversible infertility in a species that is not related to C57BL/6 male mice. In CD rats, N-butyldeoxygalactonojirimycin (NB-DGJ) caused reversible infertility at 150 mg/kg/day when administered daily as single oral dose. NB-DGJ inhibited CD rat-derived testicular β-glucosidase 2 (GBA2) activity at 10 µM but did not inhibit CD rat-derived testicular ceramide-specific glucosyltransferase (CGT) at doses up to 1000 µM. Pharmacokinetic studies revealed that sufficient plasma levels of NB-DGJ (50 µM) were achieved to inhibit the enzyme. Fertility was blocked after 35 days of treatment and reversed one week after termination of treatment. The rapid return of fertility indicates that the major effect of NB-DGJ may be epididymal rather than testicular. Collectively, our in vitro and in vivo studies in rats suggest that iminosugars should continue to be pursued as potential lead compounds for development of oral, non-hormonal male contraceptives. The study also adds evidence that GBA2, and not CGT, is the major target for the contraceptive effect of iminosugars.

Gossypol Induces Disruption of Spermatogenesis and Steroidogenesis in Male Mice

Gossypol, commonly found in cotton seeds, is hazardous to male reproductive physiology. Although several studies have indicated the toxicity of gossypol in human and animal reproduction, the mechanism of gossypol action in testes has not yet been elucidated. In the present study, we investigated the effects of gossypol in normal mouse testis cells, TM3 and TM4 cells, and in gossypol-treated C57BL/6 mice. We confirmed the antiproliferative effects of gossypol using cell viability assays, with PCNA as a proliferation marker, and cell cycle analysis. We also verified mitochondrial dysfunction and Ca²⁺ dysregulation in the cytosol of TM3 and TM4 cells, using JC-1 and Fluo-4 dyes. To confirm the cellular signaling mechanisms in testis cell lines, we performed Western blot analysis to assess the changes in MAPK and PI3K/Akt signal transduction, using their pharmacological inhibitors. Moreover, we screened the mRNA expression of genes involved in spermatogenesis and steroidogenesis in TM3 and TM4 cells. We also confirmed the mRNA expression and localization of genes regulating testis function in gossypol-treated and untreated mice testes. Collectively, we suggest that gossypol induces negative effects on testis function by reducing cell viability, mitochondrial membrane potential, and testis development-related genes in vitro and in vivo as well as by modulating the MAPK and PI3K signaling pathways.

Testosterone Is a Contraceptive and Should Not Be Used in Men Who Desire Fertility

Testosterone has a variety of functions and is commonly used in older men to treat symptoms of hypogonadism, such as decreased libido, decreased mood and erectile dysfunction. Despite its positive effects on sexual function, it has a negative effect on fertility. Exogenous testosterone therapy can negatively affect the hypothalamic-pituitary gonadal axis and inhibit the production of follicle stimulating hormone and luteinizing hormone. The purpose of this review is to discuss the contraceptive properties of testosterone therapy and to discuss strategies to increase testosterone in men with the desire to preserve fertility.

An automated smartphone-based diagnostic assay for point-of-care semen analysis

Male infertility affects up to 12% of the world's male population and is linked to various environmental and medical conditions. Manual microscope-based testing and computer-assisted semen analysis (CASA) are the current standard methods to diagnose male infertility; however, these methods are labor-intensive, expensive, and laboratory-based. Cultural and socially dominated stigma against male infertility testing hinders a large number of men from getting tested for infertility, especially in resource-limited African countries. We describe the development and clinical testing of an automated smartphone-based semen analyzer designed for quantitative measurement of sperm concentration and motility for point-of-care male infertility screening. Using a total of 350 clinical semen specimens at a fertility clinic, we have shown that our assay can analyze an unwashed, unprocessed liquefied semen sample with <5-s mean processing time and provide the user a semen quality evaluation based on the World Health Organization (WHO) guidelines with ~98% accuracy. The work suggests that the integration of microfluidics, optical sensing accessories, and advances in consumer electronics, particularly smartphone capabilities, can make remote semen quality testing accessible to people in both developed and developing countries who have access to smartphones.

Vasectomy: tips and tricks

According to data from the National Study of Family Growth, vasectomy is utilized by 6–13% of American couples for their form of contraception. Physician surveys have shown that over 500,000 men undergo vasectomies per year, and more than 75% of vasectomies are performed by urologists. This chapter provides a brief history of vasectomy, as well as recommendations for preoperative counseling, an overview of the modified no-scalpel vasectomy technique, and a brief description of the complications of vasectomy.

Suppression of spermatogenesis by testosterone undecanoate-loaded injectable in situ-forming implants in adult male rats

We have investigated the feasibility of administration of testosterone undecanoate (TU)-loaded injectable in situ-forming implant (ISFI) for contraception in adult male Sprague–Dawley rats. Male rats were treated with vehicle, TU-loaded ISFIs (540, 270 and 135 mg TU kg⁻¹) or TU injections (45 mg TU kg⁻¹ every 30 days) for 120 days. Fertility tests served for determining infertility or restoration of fertility in treated rats. Serum testosterone concentration, epididymal sperm count, motility, morphology, and histology of the testis were monitored. The TU-loaded ISFIs increased serum testosterone levels in rats steadily without fluctuation over 3 months. One month after TU administration, the epididymal sperm count decreased significantly in all experimental groups. After 3 months, the animals treated with 270 and 135 mg kg⁻¹ TU-loaded ISFIs were 100% infertile, and no implantation sites were produced in the mated females. However, some of males treated with 540 mg kg⁻¹ ISFI or TU injections were still fertile but numbers of implantation sites were also significantly lower than control values. TU-loaded ISFI at an appropriate dose has potential as a long-acting male contraceptive drug that suppresses spermatogenesis consistently over a period of 3 months.

Pipeline for contraceptive development

The high rates of unplanned pregnancy reflect an unmet need for effective contraceptive methods for women, especially for individuals with health risks such as obesity, diabetes, hypertension, and other conditions that may contraindicate use of an estrogen-containing product. Improvements in safety, user convenience, acceptability, and availability of products remain important goals of the contraceptive development program. Another important goal is to minimize the impact of the products on the environment. Development of new methods for male contraception has the potential to address many of these issues of safety for women who have contraindications to effective contraceptive methods but want to protect against pregnancy. It would also address a huge unmet need for men who want to control their fertility. Products under development for men would not introduce ecotoxic hormones into the water system.

Recombinant production of enzymatically active male contraceptive drug target hTSSK2 - Localization of the TSKS domain phosphorylated by TSSK2

The testis-specific serine/threonine kinase 2 (TSSK2) has been proposed as a candidate male contraceptive target. Development of a selective inhibitor for this kinase first necessitates the production of highly purified, soluble human TSSK2 and its substrate, TSKS, with high yields and retention of biological activity for crystallography and compound screening. Strategies to produce full-length, soluble, biologically active hTSSK2 in baculovirus expression systems were tested and refined. Soluble preparations of TSSK2 were purified by immobilized-metal affinity chromatography (IMAC) followed by gel filtration chromatography. The biological activities of rec.hTSSK2 were verified by in vitro kinase and mobility shift assays using bacterially produced hTSKS (isoform 2), casein, glycogen synthase peptide (GS peptide) and various TSKS peptides as target substrates. Purified recombinant hTSSK2 showed robust kinase activity in the in vitro kinase assay by phosphorylating hTSKS isoform 2 and casein. The ATP Km values were similar for highly and partially purified fractions of hTSSK2 (2.2 and 2.7 μM, respectively). The broad spectrum kinase inhibitor staurosporine was a potent inhibitor of rec.hTSSK2 (IC50 = 20 nM). In vitro phosphorylation experiments carried out with TSKS (isoform 1) fragments revealed particularly strong phosphorylation of a recombinant N-terminal region representing aa 1-150 of TSKS, indicating that the N-terminus of human TSKS is phosphorylated by human TSSK2. Production of full-length enzymatically active recombinant TSSK2 kinase represents the achievement of a key benchmark for future discovery of TSSK inhibitors as male contraceptive agents.

Male Contraception: Research, New Methods, and Implications for Marginalized Populations

The majority of research on contraception has focused on manipulating the female reproductive system. Recent studies have identified novel contraceptives for males, including hormonal- and nonhormonal-based therapeutics. Although these new contraceptives are still undergoing clinical trials, their development and potential future use in society necessitate serious consideration of their implications for reproductive health. Through my analysis of the research conducted on male contraception over time and the current therapeutics available, it is clear that male contraception has the potential to shift societal gender dynamics and provide males with greater control over their own reproduction. This article also identifies the implications of these novel contraceptives for marginalized populations, especially men of color and men of lower socioeconomic positions. To overcome barriers to contraception among these populations, public policy efforts are needed in order to motivate the development of programs that facilitate coverage of these new male contraceptives by health plans and to increase their availability to underserved communities. Health care providers will be responsible for educating patients about these novel male contraception options and the need to continue using existing methods (e.g., condoms) in order to prevent sexually transmitted infections. This article analyzes the research conducted on male contraception and identifies the implications of these novel therapeutics for marginalized groups of men in the United States to identify the interventions that will be necessary to help ensure that all men have access to these promising scientific innovations.

Phenolic Profiling and Evaluation of Contraceptive Effect of the Ethanolic Extract of Salsola imbricata Forssk. in Male Albino Rats

Reported researches dealing with either composition or bioactivity of Salsola imbricata are limited. This study was conducted aiming to investigate the phenolic composition of the plant and evaluate its efficacy as male contraceptive. Polyphenols, namely, phenolic acids and flavonoids, were qualitatively and quantitatively analysed by RP-HPLC in the hydrolysed methanol extract using two different wavelengths, 280 and 330 nm. The efficiency of different solvents in extracting the plant phenolics was assessed via spectrophotometric determination of the total phenolic and flavonoid contents. Acute toxicity study was carried out on the ethanolic extract to ascertain its safety prior to biological evaluation. The contraceptive effect was assessed, in male rats, by oral administration of the extract at two doses (250 and 500 mg/kg b. wt.), over a period of 65 days. HPLC analyses allowed the identification and quantification of a total of 13 and 8 components in the hydrolysed-methanol extract; the overall phenolic composition was dominated by quercitrin (12.692%) followed by coumaric acid (4.251%). Prolonged oral administration of the ethanolic extract caused slight reduction in the testis weight only. A significant decrease in the sperm count was observed (P < 0.01) in the two treated groups while significant decrease in the epididymal sperm motility was only observed in the high dose group. Morphological abnormalities were observed in sperms of treated animals. No distinct change in serum FSH, LH, and testosterone concentration was recorded. The histopathological findings supported to a high extent these results. The male contraceptive activity of Salsola imbricata could be ascribed to its phenolic components, especially quercitrin.