Risk factors for preeclampsia-eclampsia among Zimbabwean women: recurrence risk and familial tendency towards hypertension

We sought to estimate the risk of recurrence of preeclampsia-eclampsia among Zimbabwean women. Additionally, we sought to assess the extent to which family history of pregnancy-induced or chronic hypertension was predicative of the risk of developing preeclampsia-eclampsia. This hospital based case-control study was conducted at Harare Maternity Hospital, Harare Zimbabwe during the period June 1995 to April 1996. Study participants were 200 women with preeclampsia or eclampsia and 200 normotensive pregnant women serving as controls. Logistic regression procedures were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Among multiparous women, a history of any pregnancy-induced hypertension was associated with a 10.5-fold increase in risk of preeclampsia-eclampsia in a subsequent pregnancy (95% CI 4.7-23.5). Women who reported that their mother or sisters experienced pregnancy-induced hypertension were found to be at an increased risk of preeclampsia-eclampsia (OR = 2.3 and 2.6, respectively). A 2.3-fold excess risk of preeclampsia-eclampsia was associated with paturients' maternal history of chronic hypertension (95% CI 1.3-3.6). The corresponding relative risk of preeclampsia-eclampsia for women reporting to have a sister with chronic hypertension was 2.6 (95% CI 1.2-5.3). Zimbabwean women, like North American and European women, are at increased risk for the recurrence of preeclampsia-eclampsia. Findings from our study and those of others suggest a possible genetic component involved in the multifactorial aetiology of preeclampsia-eclampsia. The information provided here should be useful to clinicians involved in the management of patients with a prior history or family history of hypertension.