Change in paternity: a risk factor for preeclampsia in multiparous women?

Background: Preeclampsia is often thought of as being a disease of first pr egnancies. The incidence of preeclampsia in subsequent pregnancies, after a previous normal pregnancy is lower. However, it has been reported that thi s beneficial effect of multiparity is lost with a change in paternity. The aim of this study was to assess the impact of change in paternity on the in cidence of preeclampsia in Dutch multiparous pregnant women. Methods: 364 M ultiparous patients with hypertension (diastolic blood pressure greater tha n or equal to 100 mmHg) were identified in the obstetric database of the Ac ademic Hospital Vrije Universiteit Amsterdam for the period 1989-1996. The diagnosis in their obstetrical history (Preeclampsia, HELLP-syndrome, chron ic hypertension) was defined in a pragmatic way in view of the retrospectiv e nature of the study. The control group consisted of 281 multiparous women from a midwife clinic, with normotensive pregnancies in the same period. P atients and controls were asked, by telephone, if the index pregnancy was f rom the same partner as the previous pregnancy and what the sex of the newb orns had been in each pregnancy. Fisher's Exact test was used for statistic al analysis and P < 0.05 was considered significant. Results: The final stu dy group consisted of 333 multiparous patients with hypertension. The contr ol group consisted of 182 multiparous women without hypertension. The preva lence of new paternity was significantly higher (P < 0.0001) both for preec lamptic and HELLP patients in comparison with the controls, with an odds ra tio of 8.6 (95%CI: 3.1-23.5) and 10.9 (95%CI: 3.7-32.3), respectively. Conc lusion : This study confirms that change of partner raises the risk for pre eclampsia in subsequent pregnancies. Immune maladaptation on the fetal mate rnal interface could be an underlying mechanism. Multiparous women with a n ew partner should be approached as being primigravid women. (C) 1999 Elsevi er Science Ireland Ltd. All rights reserved.