NEW YORK — Women who develop preeclampsia should be counseled about the risk in subsequent gestations and strategies to contain these risks, according to Baha M. Sibai, M.D.
In addition, more general implications about health in later life should be discussed with the patient, said Dr. Sibai, professor and chairman of obstetrics and gynecology at the University of Cincinnati. He made his report at an obstetrics symposium sponsored by Columbia University and New York Presbyterian Hospital.
About 20%-30% of women who have had an episode of preeclampsia will develop it in a subsequent pregnancy, which makes this history at least as significant a risk factor for future preeclampsia as chronic hypertension, renal disease, and pregestational diabetes.
The earlier in the first gestation preeclampsia developed, the higher the risk of recurrence in the next: The condition returned in more than half of women who had their first episode before week 27, compared with a 40% recurrence when the index episode was between week 27 and 30, and 20% at week 37 or after.
A severe episode of preeclampsia or eclampsia also is associated with a worse outcome in subsequent pregnancies, with an increased risk of intrauterine growth retardation, perinatal loss, and abruptio placentae. Here, too, the earlier the episode occurred in the first gestation, the greater the risk to the second, Dr. Sibai said. Preventive measures can contain the risk of preeclampsia and poor outcome in subsequent pregnancies. These include attention to weight, blood pressure, and blood sugar. “Aggressive control of hypertension before and early in pregnancy can reduce the risk of preeclampsia from 50% to [a range of] 10%-15%,” Dr. Sibai said.
In women with diabetes, good control of blood sugar from early in the pregnancy will markedly reduce the rate of preeclampsia, he said.
In vitro fertilization should involve the transfer of no more than two embryos, as a risk-containment measure.
A number of other strategies have been suggested to reduce the incidence of preeclampsia. Prophylactic aspirin has had particular attention, but a large multicenter trial found no difference in outcome among women at highest risk.
A metaanalysis of studies using calcium supplementation likewise found no benefit, he said.
Women who have had preeclampsia should also be counseled about its implications for health problems later in life, such as chronic hypertension, diabetes, and ischemic heart disease. “Preeclampsia is a manifestation of underlying silent disease that will develop into a clinical condition that develops later; it doesn't cause [later health problems],” Dr. Sibai said.
The incidence of chronic hypertension in women who have had a severe episode of preeclampsia, at an average follow-up of 7 years, ranges from 7% when the preeclampsia developed after 37 weeks, to 25% when it had developed before 27 weeks.
The risk of later renal and cardiovascular disease is particularly heightened after an episode of preeclampsia that developed before 30 weeks, that was severe, or that recurred, Dr. Sibai said.
In fact, preeclampsia during one singleton gestation doubles the risk of ischemic heart disease and raises it nearly threefold when preeclampsia is severe. Gestational hypertension without proteinuria is associated with a 1.6 relative risk of ischemic heart disease.
“The risk factors for preeclampsia and coronary artery disease overlap considerably,” Dr. Sibai observed.