Researchers conducted this study to examine PCOS and PIH’s association within a large population of pregnant women in an integrated healthcare system. 

This retrospective study utilized a source cohort of 1023 women with PCOS and 1023 women without PCOS who had a delivered pregnancy within Kaiser Permanente Northern California. Preexisting hypertension was defined by hypertension diagnosis, treatment, or elevated blood pressure before 20 weeks of gestation. PIH development, including gestational hypertension, preeclampsia/eclampsia, or HELLP, was ascertained by chart review. Among women without preexisting hypertension who had a singleton pregnancy, the association of PCOS and PIH was examined using multivariable logistic regression. 

Among 1902 women with a singleton pregnancy, 101 PCOS and 36 non-PCOS women had preexisting hypertension and were excluded. Of the remaining 1765 women, those with PCOS were slightly older, more likely to be obese, nulliparous, and conceive with fertility treatment; they also had a higher incidence of PIH, including gestational hypertension preeclampsia or HELLP. PCOS was associated with increased PIH odds, remaining significant after adjusting for age, race/ethnicity, nulliparity, and fertility treatment.

Compared to women without PCOS, women with PCOS are at higher risk for PIH, but this association was not independent of weight status.