Objective To examine the effect of cardiovascular risk factors before pregnancy on risk of pre-eclampsia. Design Population based prospective study. Setting Linkage between a Norwegian population based study (Nord-Trøndelag health study, HUNT-2) and Norway's medical birth registry. Participants 3494 women who gave birth after participating in the Nord-Trøndelag health study at baseline; of whom 133 (3.8%) delivered after a preeclamptic pregnancy. Main outcome measure Odds ratio of developing preeclampsia. Results After adjustment for smoking; previous preeclampsia; parity; maternal age, education, and socioeconomic position; and duration between baseline measurements and delivery, positive associations were found between prepregnancy serum levels of triglycerides, cholesterol, low density lipoprotein cholesterol, non-high density lipoprotein cholesterol, and blood pressure and risk of pre-eclampsia. The odds ratio of developing preeclampsia for women with baseline systolic blood pressures greater than 130 mm Hg (highest fifth) was 7.3 (95% confidence interval 3.1 to 17.2) compared with women with systolic blood pressures less than 111 mm Hg (lowest fifth). Similar results were found for nulliparous and parous women. Women who used oral contraceptives at baseline had half the risk of pre-eclampsia compared with never or former users (0.5, 0.3 to 0.9). Conclusion Women with cardiovascular risk factors may be predisposed to pre-eclampsia.

Background-Preeclampsia and gestational hypertension are associated with increased risk for cardiovascular disease later in life. We have assessed whether the effect can be attributed to factors that operate in pregnancy or to prepregnancy risk factors that are shared by both disorders. Methods and Results-Longitudinal data from 2 consecutive waves of a Norwegian population-based study (the Nord-Trøndelag Health Study [HUNT]) were combined with data from the Medical Birth Registry of Norway. Among 24 865 women who had participated in both HUNT 1 and 2, we indentified 3225 women with a singleton birth between the 2 studies who had standardized measurements of blood pressure, serum lipids, and body mass index. The crude results showed that women who experienced preeclampsia or gestational hypertension in pregnancy had substantially higher levels of body mass index and systolic and diastolic blood pressures and unfavorable lipids compared with other women. However, after adjustment for prepregnancy measurements, the difference in body mass index was attenuated by Ͼ65%, and the difference in blood pressure was attenuated by Ϸ50%. In relation to high-density lipoprotein cholesterol and triglycerides, differences between the groups were attenuated by 40% and 72%, respectively. Conclusions-These results suggest that the positive association of preeclampsia and gestational hypertension with postpregnancy cardiovascular risk factors may be due largely to shared prepregnancy risk factors rather than reflecting a direct influence of the hypertensive disorder in pregnancy. (Circulation. 2010;122:579-584.)

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