Gynecology is the specialty that learned to keep both mother and baby safe.

In June 2002, The Lancet published one of the largest trials ever run in pregnancy. Pre-eclampsia raises a pregnant woman’s blood pressure, and it can end in seizures that kill her. Doctors gave magnesium sulphate to prevent those seizures, but nobody had proved it worked. The trial gave 10,141 women with pre-eclampsia, in 33 countries, magnesium sulphate or placebo. Seizures occurred in 0.8% on magnesium, against 1.9% on placebo. That is 58% fewer. Fewer mothers died too. The cost was side effects, in 24% of women against 5%. A cheap old drug had been proved to save mothers’ lives.

Five months later, in November 2002, the New England Journal of Medicine published a trial of a vaccine against a cancer. About one adult in five catches HPV type 16, a virus that can lead to cervical cancer. The trial gave 2,392 young women three doses of a vaccine against it, or placebo. Over the next year and a half, persistent infection occurred at a rate of 3.8 per 100 women a year on placebo. On the vaccine, the rate was zero. All nine cases of early cervical precancer were in women who got placebo. A cancer had become something a vaccine could prevent.

Seven years after that, in October 2009, a trial settled a quieter question. Many pregnant women have mildly raised blood sugar. Nobody knew whether treating it helped. The trial gave 958 such women either diet advice, glucose checks and insulin if needed, or usual care. Treatment did not change the main outcome, a mix of stillbirth and newborn complications. But it halved the number of oversized babies, 7.1% against 14.5%. It cut shoulders getting stuck at birth, 1.5% against 4.0%. It cut caesareans, 26.9% against 33.8%. And it cut high blood pressure in the mother, 8.6% against 13.6%. A mild problem had been worth treating after all.

These are three of the thousands of studies that shaped modern gynecology. They taught gynecology that a cheap drug could keep mothers alive, that a vaccine could prevent a cancer, and that treating a mild problem in pregnancy could spare both mother and baby, and each time the answer was in a paper years before it was in a textbook.

It is still happening. Recently, in January 2026, The Lancet published a trial that prevents pre-eclampsia by choosing when a baby is born. Nothing reliable had reduced pre-eclampsia at term. The trial screened 8,094 women at 36 weeks for their risk, at two hospitals in the UK. Women at high risk were offered a planned birth a little early. The others had usual care. Pre-eclampsia occurred in 3.9% of births in the screened group, against 5.6% with usual care, a 30% reduction. Emergency caesareans and admissions to neonatal care did not rise. Serious adverse events did not differ. A disease the field could only treat could now be headed off. Practice follows the literature as it goes. It is a good culture. It has exactly one cost.