What causes pregnancy induced hypertension?

No one knows: There have been many theories, but no one knows what causes pregnancy induced hypertension.

Still a mystery: My OB chairman told us this about a famous hospital where pioneers in pregnancy worked and studied complications like toxemia. It was called chicago lying-in hospital; it evolved into labor and delivery of the u chicago medical center. Nearby is a row of plaques of famous researchers. There is one for the person who discovers the cause of preeclampsia. After all of these years, it is still empty.

PIH: There are four types of high blood pressure (hypertension) that can occur in pregnancy: preeclampsia, chronic hypertension, preeclampsia superimposed on chronic hypertension and gestational hypertension. Please see this link for complete info: http://bit.Ly/extems.

Chronic/preeclampsia: Hypertension occurs in 3-4% pregnancies. Most times it is a reflection of essential HTN (perhaps exacerbated by wt gain and increased plasma volume). Htn occurring after 20 weeks might reflect preeclampsia and if associated neurological changes, eclampsia . Thyroid abnormalities later in pregnancy can also affect BP and cause htn.