Few medical topics carry as much misinformation as abortion. Claims that it causes infertility, breast cancer, lasting psychological trauma, or that restricting it increases birth rates circulate widely — in social media posts, political debates, and even some healthcare settings. But what does the actual medical evidence say?

This article is not a political argument. It is a review of what large-scale, peer-reviewed research — published in journals like The Lancet, The New England Journal of Medicine, and Obstetrics & Gynecology — has found about the safety of abortion, its effects on fertility and cancer risk, the psychological outcomes that follow, and the public health consequences of restricting access. The evidence base is extensive: decades of data from millions of patients across dozens of countries.

Whether you are tracking your reproductive health, preparing for a medical conversation, or simply trying to separate fact from myth, the research deserves to be presented plainly and accurately. That is what follows.

How Safe Is Abortion as a Medical Procedure?

The single most important statistic in this entire discussion: abortion, when performed according to modern clinical guidelines, is one of the safest procedures in medicine.

A landmark study published in Obstetrics & Gynecology analyzed over 54,000 abortions and found a major complication rate of 0.23% — less than one quarter of one percent. The mortality rate for legal abortion in the United States is approximately 0.7 deaths per 100,000 procedures, according to data from the Centers for Disease Control and Prevention (CDC). To put that in context, the maternal mortality rate for carrying a pregnancy to term in the U.S. is roughly 32.9 deaths per 100,000 live births — approximately 47 times higher.

The World Health Organization (WHO) is unambiguous: when performed by trained providers using recommended methods appropriate to the gestational age, abortion is a very safe procedure. The WHO's clinical guidelines, updated in 2022, emphasize that the risks of abortion are far lower than the risks of continued pregnancy and childbirth.

Complication rates increase with gestational age, which is why the vast majority of abortions occur in the first trimester. Data from the CDC show that over 93% of abortions in the United States are performed at or before 13 weeks of gestation, and roughly 80% occur before 10 weeks. First-trimester abortion — whether surgical (aspiration) or medical (mifepristone plus misoprostol) — carries a complication rate comparable to that of a routine dental procedure.

Medication abortion, which now accounts for over half of all abortions in the U.S., has been studied extensively since the FDA approved mifepristone in 2000. A systematic review published in Contraception analyzed data from over 45,000 women and found that medication abortion has a serious adverse event rate of less than 0.4%. The most common side effects — cramping, bleeding, nausea — are expected and temporary.

Myth: Abortion Causes Infertility

This is perhaps the most persistent myth, and one that causes significant anxiety. The medical evidence does not support it.

A large Danish cohort study published in Human Reproduction followed over 11,800 women after first-trimester induced abortion and found no increased risk of subsequent infertility. Women who had undergone an uncomplicated first-trimester abortion had the same rates of subsequent pregnancy as those who had never had one.

A systematic review in Fertility and Sterility examined multiple studies on the relationship between induced abortion and subsequent fertility outcomes. The authors concluded that first-trimester abortion — whether surgical or medical — does not increase the risk of ectopic pregnancy, miscarriage, or infertility in subsequent pregnancies.

The American College of Obstetricians and Gynecologists (ACOG) states clearly: having an abortion does not affect future fertility. This position is based on decades of accumulated clinical data.

Where does the myth come from? Historically, when abortions were performed under unsafe conditions — without sterile technique, by untrained providers — infections were common. Pelvic inflammatory disease from untreated infections can indeed damage fallopian tubes and affect fertility. But this is a consequence of unsafe conditions, not of the procedure itself. Modern, legal abortion performed in clinical settings has essentially eliminated this risk.

There is one nuance worth noting: multiple surgical dilation and curettage (D&C) procedures may carry a small increased risk of cervical insufficiency or uterine adhesions (Asherman syndrome) in rare cases. However, this risk is very low, and the standard first-trimester aspiration technique used today is gentler than the older D&C method. Medical abortion carries no such risk at all, since it involves no instrumentation of the uterus.

Myth: Abortion Causes Breast Cancer

The claimed link between abortion and breast cancer has been studied extensively — and rejected by every major cancer research organization in the world.

The largest and most rigorous study on this question was a prospective cohort study of over 1.5 million Danish women, published in The New England Journal of Medicine in 1997. It found no increased risk of breast cancer among women who had had induced abortions, regardless of the number of abortions, the woman's age at the time, or the gestational age at termination.

A comprehensive systematic review and meta-analysis published in The Lancet in 2004 analyzed data from 53 epidemiological studies across 16 countries, involving over 83,000 women with breast cancer. The authors concluded that pregnancies that end in induced abortion do not increase a woman's risk of developing breast cancer.

The National Cancer Institute (NCI) convened an expert workshop in 2003 specifically to evaluate this question. The panel of over 100 of the world's leading experts concluded that induced abortion is not associated with an increase in breast cancer risk. The NCI's official position has not changed since.

Why did this myth gain traction? Earlier, smaller case-control studies sometimes found a weak association, but these suffered from a well-documented problem called recall bias: women with breast cancer are more likely to accurately report (or over-report) their complete reproductive history, including abortions, while healthy control subjects are more likely to underreport. When researchers used prospective data — collected before any cancer diagnosis — the association disappeared entirely.

ACOG, the WHO, and the American Cancer Society all concur: there is no causal link between abortion and breast cancer.

What About Mental Health?

The claim that abortion causes lasting psychological harm — sometimes called "post-abortion syndrome" — is not recognized as a diagnosis by any major medical or psychological organization. But the question of how abortion affects mental health has been studied in detail.

The most comprehensive review to date was conducted by the National Academies of Sciences, Engineering, and Medicine (NASEM) in 2018. After reviewing all available evidence, the committee concluded that having an abortion does not increase a woman's risk of depression, anxiety, or post-traumatic stress disorder (PTSD) compared to carrying an unwanted pregnancy to term.

The Turnaway Study, a longitudinal research project led by the University of California, San Francisco, followed nearly 1,000 women over five years — some who received a wanted abortion and some who were turned away. The findings were striking: women who were denied an abortion reported higher levels of anxiety and lower life satisfaction in the short term compared to those who received one. Over time, the most common emotion reported by women who had an abortion was relief. Ninety-five percent of women who had abortions reported that it was the right decision for them when followed up over five years.

That said, some women do experience sadness, grief, or complicated feelings after an abortion. This is normal and valid — but it is not the same as a psychiatric disorder. Emotions after any significant life decision can be mixed. The evidence shows that pre-existing mental health conditions and lack of social support are far stronger predictors of post-abortion emotional difficulty than the abortion itself.

The American Psychological Association's Task Force on Mental Health and Abortion reviewed all available studies and concluded: "The best scientific evidence published indicates that among adult women who have an unplanned pregnancy, the relative risk of mental health problems is no greater if they have a single elective first-trimester abortion than if they deliver that pregnancy."

Medication Abortion: What the Evidence Shows

Medication abortion — using a combination of mifepristone and misoprostol — has transformed reproductive healthcare since its introduction. It now accounts for more than half of all abortions in the United States and is widely used globally.

The safety profile is well-established. A systematic review published in The Lancet examined data from multiple countries and found that medication abortion is effective in 95-98% of cases when used within the recommended gestational age (up to 10-12 weeks depending on protocol). Serious complications requiring hospitalization occur in fewer than 0.4% of cases.

The FDA's post-market surveillance data, covering over 5 million women who used mifepristone between 2000 and 2023, show a fatality rate of less than 0.001%. To put this in perspective, common over-the-counter medications like acetaminophen (Tylenol) and ibuprofen carry comparable or higher rates of serious adverse events when used at scale.

A large retrospective cohort study published in Obstetrics & Gynecology compared outcomes of medication abortion managed via telehealth with in-person care and found no significant difference in complication rates — an important finding given the expansion of telemedicine access.

The WHO includes both mifepristone and misoprostol on its Model List of Essential Medicines, recognizing them as safe and necessary components of reproductive healthcare.

Do Abortion Restrictions Reduce Abortion Rates?

One of the most persistent assumptions in the policy debate is that restricting access to abortion leads to fewer abortions and more births. The global epidemiological evidence does not support this.

A comprehensive study published in The Lancet in 2020 analyzed abortion data from 1990 to 2019 across 150 countries. The key finding: abortion rates are similar in countries where abortion is broadly legal and countries where it is restricted. The global rate in countries with broadly legal abortion was 40 per 1,000 women of reproductive age, compared to 36 per 1,000 in countries with heavy restrictions. The difference was not statistically significant.

What does change dramatically is safety. In countries where abortion is restricted, the proportion of abortions that are unsafe rises sharply. The WHO estimates that approximately 45% of all abortions worldwide are unsafe, and nearly all of these (97%) occur in developing countries where access is restricted. Unsafe abortions account for an estimated 4.7-13.2% of maternal deaths globally.

A study published in JAMA Internal Medicine examined what happened in Texas after the state implemented severe restrictions on abortion clinics in 2013. The study found that the restrictions did not reduce abortion rates — women traveled out of state, ordered medications online, or sought other means. What did increase was self-managed abortion without medical supervision.

The Guttmacher Institute's analysis of global data consistently shows that the factor most strongly associated with lower abortion rates is not legal restriction but rather access to effective contraception. Countries with comprehensive sex education and easy access to modern contraceptives consistently have the lowest abortion rates in the world — regardless of their legal framework. For an evidence-based overview of available methods, see our guide to contraception and birth control options.

What Actually Reduces Abortion Rates

If legal restrictions do not meaningfully reduce abortion rates, what does? The evidence points clearly to two interventions: contraception access and comprehensive sex education.

The Colorado Family Planning Initiative provided long-acting reversible contraceptives (LARCs) — IUDs and implants — free of charge to low-income women. Over a six-year period, the teen birth rate dropped by 54% and the teen abortion rate dropped by 64%. A study published in Obstetrics & Gynecology confirmed these dramatic results.

The Contraceptive CHOICE Project at Washington University in St. Louis removed cost barriers to contraception for over 9,000 women. The result: unintended pregnancy rates and abortion rates among participants dropped to a fraction of the national average. The findings, published in The New England Journal of Medicine, showed that when women have access to the most effective contraceptive methods without cost barriers, unintended pregnancies plummet.

At the international level, the data tell the same story. Western European countries — which combine legal abortion access with universal contraceptive coverage and comprehensive sex education — have the lowest abortion rates in the world, often below 10 per 1,000 women of reproductive age. This is roughly one-quarter the rate seen in regions where abortion is heavily restricted but contraception is less accessible.

The WHO has consistently identified contraception access as the most effective strategy for reducing unintended pregnancies and, by extension, abortions.

Long-Term Physical Health After Abortion

Beyond fertility and cancer, what does the research say about other long-term physical health outcomes?

The NASEM 2018 report — the most comprehensive review of abortion safety evidence ever conducted — examined outcomes including subsequent pregnancy complications, cardiovascular health, and overall mortality. The conclusion: legal abortion performed by trained clinicians has no long-term health risks beyond those of any brief surgical or medical procedure.

Specifically, the evidence shows:

  • Subsequent pregnancy outcomes: Multiple large cohort studies have found no increased risk of preterm birth, low birth weight, or placenta previa after a first-trimester abortion. A systematic review in BJOG confirmed these findings across studies involving hundreds of thousands of women.

  • Cervical health: First-trimester aspiration abortion does not increase cervical cancer risk. Pap smear screening recommendations are the same for women who have had abortions as for those who have not.

  • Mortality: A Finnish registry study that followed 9,192 women for up to 25 years after abortion found no increased long-term mortality compared to women who gave birth.

Tracking your reproductive health data over time — menstrual cycle patterns, symptoms, and any procedures — helps you and your healthcare provider spot changes early. WatchMyHealth's cycle tracking feature allows you to log cycle data, symptoms, and health events so you have a complete picture when you need it.

Unsafe Abortion: The Real Danger

While legal, properly performed abortion is extremely safe, unsafe abortion remains a major global health crisis. Understanding this distinction is essential.

The WHO defines unsafe abortion as a procedure for terminating an unintended pregnancy carried out either by persons lacking the necessary skills or in an environment that does not conform to minimal medical standards, or both. Globally, an estimated 25 million unsafe abortions occur each year.

The consequences are severe. According to WHO data, unsafe abortion is one of the leading causes of maternal mortality worldwide, contributing to an estimated 39,000 deaths per year and millions of hospitalizations for complications including hemorrhage, infection, and organ damage.

The pattern is starkly consistent across regions and time periods: where legal access to safe abortion is restricted, rates of unsafe abortion rise, and maternal morbidity and mortality increase. When Romania banned abortion in 1966, the maternal mortality rate increased dramatically; when the ban was lifted in 1989, maternal mortality dropped immediately. Similar patterns have been documented in South Africa, Nepal, and Ethiopia after those countries liberalized their abortion laws.

This is not a theoretical concern. A study in The Lancet estimated that making abortion broadly legal could prevent 26,000 maternal deaths annually. The evidence makes the public health calculus clear: the safety of abortion depends overwhelmingly on the conditions under which it is performed, not on the procedure itself.

Making Informed Decisions About Your Health

Reproductive health decisions are deeply personal, and making them well requires accurate information. Here is what the medical evidence, taken as a whole, tells us:

  • Abortion performed under proper medical conditions is very safe — safer, statistically, than carrying a pregnancy to term
  • It does not cause infertility when performed according to current clinical guidelines
  • It does not cause breast cancer — this has been definitively studied and rejected
  • It does not cause psychiatric disorders — the most common long-term emotion reported is relief
  • Legal restrictions do not reduce abortion rates — but they dramatically increase the proportion of unsafe abortions
  • Contraception access is the most effective way to reduce abortions — demonstrated consistently across countries and decades

Whatever decisions you face regarding your reproductive health, they should be grounded in evidence rather than myths. Tracking your health data — cycle patterns, symptoms, medications, and any changes you notice — gives you a foundation for informed conversations with your healthcare provider. WatchMyHealth's cycle tracking and symptom logging tools are designed to help you maintain that record over time, so that when you need it, you have a clear, data-driven picture of your health.

If you are making a reproductive health decision, consult a qualified healthcare provider who can discuss the evidence as it applies to your specific situation. The research is there. Use it.