But the NIH just sounded an alarm that the pre-eclampsia rate rose by nearly a third during the 1990s. Pre-eclampsia is diagnosed late in pregnancy with a sudden rise in blood pressure, protein in urine, and swelling of the hands, face or feet. Other signs are pain in the upper right abdomen, and headaches or visual disturbances. Scientists now believe a pre-eclamptic woman's vessels are constricted from the beginning, reducing blood flow to the fetus and her own organs, thus potentially causing kidney and other damage. Some women worsen to have seizures, called eclampsia.
Some cases are mild and mothers are prescribed bed rest in hopes of bringing the baby to term.
Severe cases may require an immediate Caesarean section despite the risks of prematurity. While only a few hundred American women a year die from pregnancy, pre-eclampsia does account for 16 percent of maternal deaths. In developing countries that can't deliver babies early or treat seizures with magnesium as U.S. doctors do, it kills thousands. At least part of the reason is more women delaying childbirth until past age 35, and a rise in multiple births. Now, doctors are hunting other substances that may directly affect blood vessels.