Birth control

• 1. Introduction

  ›

  The Egyptian Ebers Papyrus from 1550 BC carries one of the earliest written recipes for birth control: honey, acacia leaves, and lint, packed into the vagina to block sperm. Even older, the Kahun Papyrus from 1850 BC offers a similar prescription. Birth control, also called contraception, has been attempted since ancient times. Yet effective and safe methods only arrived in the 20th century.

  For most of human history, the methods people trusted were probably useless. Some involved tying weasel testicles around the thighs during sex. Others demanded drinking dissolved copper salts. What changed? How did a practice once deemed immoral by powerful institutions become a service that human rights agreements now require governments to provide? And why, even today, are about 222 million women who want to avoid pregnancy not using a modern method?

• 2. The Effectiveness Ladder

  ›

  A woman using no birth control at all has an 85% chance of pregnancy within a year. Against that baseline, methods sort into a clear hierarchy. The most effective are long-acting and require no ongoing health care visits.

  Surgical sterilization, implantable hormones, and intrauterine devices all post first-year failure rates below 1%. The implant sits at the bottom of the failure scale, at 0.05%. Vasectomy follows closely, and the copper IUD lands near 0.8%. These methods share one trait: once in place, they do not depend on a person remembering anything.

  Hormonal pills, patches, and vaginal rings can also fall below 1% failure, but only with strict adherence. With typical use, that figure climbs to about 9%, driven by inconsistent use. The gap between perfect use and typical use is where most unplanned pregnancies live. The combination pill, for instance, drops from a 9% typical failure rate to 0.3% with perfect use.

  Further down sit the barrier and behavioral methods. Male condoms carry an 18% typical failure rate, diaphragms with spermicide 12%, and withdrawal 22%. The American Academy of Pediatrics recommends long-acting reversible birth control as the first line for young individuals, precisely because it removes the human error that sinks the rest.

• 3. How Hormones Intervene

  ›

  Combined oral contraceptive pills contain both estrogen and a progestin, while progestogen-only pills, sometimes called minipills, carry just one. Both work mainly by inhibiting ovulation and thickening cervical mucus, and may also change the uterine lining to decrease implantation. Taken accidentally during pregnancy, neither increases the risk of miscarriage nor causes birth defects.

  Combined hormonal contraceptives raise the risk of venous and arterial blood clots. Venous clots increase on average from 2.8 to 9.8 per 10,000 women years, still lower than the risk during pregnancy itself. Because of this, they are not recommended for women over 35 who continue to smoke. They appear in clinical decision tools like the DASH score and the PERC rule, both used to predict clot risk.

  The benefits run alongside the risks. Combined oral contraceptives reduce the risk of ovarian and endometrial cancer, leave breast cancer risk unchanged, and often ease menstrual bleeding and cramps. The lower estrogen dose from a vaginal ring may reduce breast tenderness, nausea, and headache.

  Progestin-only methods carry no increased clot risk, so women with a history of venous clots can use them. They do not affect milk production, making them suitable for breastfeeding women. The progestins drospirenone and desogestrel reduce androgenic side effects but raise clot risk, so they are not first line. Hormonal contraceptives remain available only for women, though versions for men have been clinically tested.

• 4. Barriers And Devices

  ›

  Globally, condoms are the most common method of birth control. Male condoms block ejaculated sperm from entering a partner's body, and modern ones are most often latex, though some use polyurethane or lamb's intestine. Their appeal is practical: inexpensive, easy to use, with few adverse effects. Usage varies sharply by country. In Japan, about 80% of couples using birth control use condoms, compared with about 25% in Germany and 18% in the United States. Condoms made from animal intestines, notably, do not help prevent the spread of sexually transmitted infections like HIV/AIDS.

  Contraceptive sponges combine a barrier with a spermicide and must be placed over the cervix. Their first-year failure rate depends on whether a woman has given birth before: 24% for those who have, 12% for those who have not. A sponge can go in up to 24 hours before intercourse and must stay in place for at least six hours afterward. Allergic reactions and even toxic shock syndrome have been reported.

  Intrauterine devices are small, often T-shaped, and contain either copper or levonorgestrel. The copper version fails about 0.8% of the time in the first year; the levonorgestrel version, 0.2%. With more than 180 million users worldwide, the IUD is the most widely used form of reversible contraception. An earlier model, the Dalkon shield, was linked to pelvic inflammatory disease, a hazard that current models do not carry for those without infections at insertion.

• 5. The Permanence Question

  ›

  Vasectomy and tubal ligation offer near-permanent results, but they carry very different burdens. Short-term complications are twenty times less likely from a vasectomy than from a tubal ligation. After a vasectomy, scrotal swelling and pain usually resolve within one or two weeks, though chronic scrotal pain affecting quality of life follows in about 1 to 2% of men. With tubal ligation, complications occur in 1 to 2% of procedures, with the serious ones usually tied to anesthesia.

  Regret tracks closely with timing and age. About 6% of women sterilized after age 30 regret it, against 20 to 24% of those sterilized within a year of delivery and before 30. Fewer than 5% of men regret sterilization, with the likeliest regretters being younger, childless, or in unstable marriages. In one survey of biological parents, 9% said they would not have had children if they could choose again.

  Reversal is possible but uncertain. Pregnancy success after tubal reversal ranges from 31 to 88%, with a heightened risk of ectopic pregnancy. After vasectomy reversal, the chance of fathering a child runs from 38 to 84%, falling the longer the gap since the original procedure. In women, the desire for reversal often follows a change in spouse. Non-surgical sterilization is also being explored, with researchers like Fahim studying high-intensity ultrasound that can selectively destroy germ cells without altering testosterone levels.

• 6. Timing Without Tools

  ›

  Behavioral methods regulate the timing or manner of intercourse rather than introducing any device. With perfect use, the first-year failure rate may sit around 3.4%, but poorly used it can approach 85%. The distance between those two numbers defines the entire category.

  Fertility awareness methods identify the most fertile days by monitoring basal body temperature, cervical secretions, or the day of the cycle. Their typical first-year failure rate is 24%, while perfect use ranges from 0.4 to 5% depending on technique. The symptothermal variant, combining temperature with another sign, has shown 20% failure overall and 0.4% with perfect use. About 3.6% of couples worldwide rely on these methods.

  The withdrawal method, also called coitus interruptus, means ending intercourse before ejaculation. Its main risk is mistiming. First-year failure runs from 4% with perfect use to 22% with typical use, and some medical professionals do not count it as birth control at all. Evidence on pre-ejaculatory fluid is thin: one trial found sperm in 10 of 27 volunteers. About 3% of couples use withdrawal.

  The lactational amenorrhea method depends on natural postpartum infertility. If a baby under six months is exclusively breastfed and the mother is not menstruating, an estimated 93 to 99% of women are protected in the first six months. Feeding formula, pumping, a pacifier, or solids all raise the chance of pregnancy. In women who do not breastfeed, fertility may return as early as four weeks after delivery.

• 7. The Ancient Search

  ›

  Silphium, a giant fennel native to north Africa, may have served as birth control in ancient Greece and the ancient Near East. It grew so desirable that by the first century AD it was worth more than its weight in silver. By late antiquity, it was fully extinct, harvested out of existence.

  Aristotle, who lived from about 384 to 322 BC, recommended applying cedar oil to the womb before intercourse, a method probably effective only on occasion. A Hippocratic text advised drinking a copper salt dissolved in water, claiming a year of protection. The later writer Soranus of Ephesus, who lived from about 98 to 138 AD, pointed out this method was both ineffective and dangerous. Soranus tried to build a list of reliable methods on rational principles, rejecting superstition and amulets in favor of wool-based vaginal plugs covered in oils.

  Medieval Europe layered moral judgment over folk practice. The Catholic Church deemed any effort to halt pregnancy immoral, yet women still used coitus interruptus and inserted lily root and rue. The oldest condoms found to date were recovered in the ruins of Dudley Castle in England, dated to 1640, made of animal gut and likely used during the English Civil War to prevent infection. Casanova, in 18th-century Italy, described a lambskin covering, but condoms only became widely available in the 20th century.

• 8. Naming The Movement

  ›

  In 1914, Margaret Sanger and Otto Bobsein popularised the phrase birth control. At the time, the Comstock Law made distributing birth control information illegal, and that same year Sanger jumped bail after her arrest and fled to the United Kingdom. There, influenced by Havelock Ellis, she sharpened her argument that women needed to enjoy sex without fearing pregnancy, and saw a more flexible diaphragm in a Dutch clinic.

  Back in the United States in 1916, Sanger opened a short-lived clinic in the Brownville section of Brooklyn with her sister, Ethel Bryne. Authorities shut it down after eleven days and arrested her, and the publicity sparked activism nationwide. Her first husband, William Sanger, distributed copies of Family Limitation, and her second, James Noah H. Slee, became the movement's main funder. In 1921 she founded the American Birth Control League, which later became the Planned Parenthood Federation of America.

  Britain moved in parallel. The Malthusian League, built on the ideas of Thomas Malthus, formed in 1877 to advocate for family planning. In 1921 Marie Stopes opened the first permanent birth-control clinic in Britain, where midwives taught the use of a cervical cap. In April 1930 a Birth Control Conference gathered 700 delegates, and three months later the Ministry of Health let local authorities give birth-control advice in welfare centres.

  Sanger's reach extended into the laboratory. In the 1950s she helped fund research by John Rock and biologist Gregory Pincus that produced the first hormonal contraceptive pill, later called Enovid. The first human trials ran on patients at the Worcester State Psychiatric Hospital, followed by clinical testing in Puerto Rico. Participants were not fully informed of the medical implications, and the approved method was never made available to them afterward.

  About 222 million women who want to avoid pregnancy in developing countries are not using a modern method, 53 million of them in sub-Saharan Africa and 97 million in Asia. The shortfall produces 54 million unplanned pregnancies and nearly 80,000 maternal deaths a year. Many countries restrict access for religious or political reasons, and poverty compounds the gap.

  The stakes are measured in lives. Birth control use in developing countries has cut deaths around the time of pregnancy by 40%, roughly 270,000 deaths prevented in 2008, and could prevent 70% if full demand were met. Lengthening the time between pregnancies improves both delivery outcomes and child survival, since outcomes worsen when a mother conceives within eighteen months of a previous birth.

  The economic case is concrete. The United Nations estimates that every dollar spent on family planning saves two to six dollars, with copper IUDs producing the greatest savings. A pregnancy, delivery, and newborn care in the United States averaged $21,000 for a vaginal delivery and $31,000 for a caesarean as of 2012. Raising a child born in 2011 was projected to cost an average US family $235,000 over 17 years.

  Usage patterns differ across the map. In the developing world, 35% of birth control is female sterilization, 30% IUDs, 12% oral contraceptives, 11% condoms, and 4% male sterilization. Contraceptive use among women in sub-Saharan Africa rose from about 5% in 1991 to about 30% in 2006. The United Nations launched the Every Woman Every Child movement in 2010, aiming to add 120 million modern birth control users across the world's 69 poorest countries by 2020.

  On the 13th of July 2023, the FDA approved Opill, the first daily oral nonprescription over-the-counter birth control pill in the United States, expected to outperform condoms at preventing unintended pregnancy. Made by Perrigo, a pharmaceutical company based in Dublin, the pill was expected to reach shelves in 2024. It marked a turn toward a long-debated goal: birth control without a prescription gate.

  Religions divide sharply on the ethics. In 1968 the Roman Catholic Church reaffirmed that only natural family planning is permissible, though many self-identified Catholics in developed countries report using other methods. The Greek Orthodox Church allows a possible exception within marriage, including for spacing births. Among Protestants, views span from the Quiverfull movement, which supports none, to those allowing every method. Judaism ranges from the stricter Orthodox sect to the more permissive Reform sect, while a common Buddhist view accepts preventing conception but not intervening after it.

  US law shifted through the courts. The 1936 ruling in United States v. One Package of Japanese Pessaries held that prescribing contraception to protect health was not illegal under the Comstock Laws. The Supreme Court's Griswold v. Connecticut in 1965 and Eisenstadt v. Baird in 1972 effectively voided the remaining restrictions, extending a right to privacy first to married then to single people. In 1966, President Lyndon B. Johnson began endorsing public funding for family planning.

  Research keeps pushing at the edges. The serine/threonine-protein kinase STK33 is indispensable for male fertility, and an inhibitor called CDD-2807 has induced reversible infertility in mice without measurable toxicity. September 26 is World Contraception Day, devoted to a vision of a world where every pregnancy is wanted.