Hyperemesis gravidarum (HG) is characterized by severe and persistent nausea and vomiting during pregnancy. Even though not well understood, there are some signs that there is a relationship between HG and preeclampsia. Women with one are more likely to have the other. In one study in England, researchers found that women with HG were slightly more likely to develop preeclampsia and twice as likely to experience seizures due to preeclampsia compared to women without HG. In another study, women with HG that persists into the 2nd trimester are more than twice as likely to experience preeclampsia.
Preeclampsia is a complication of pregnancy which includes new-onset high blood pressure, protein in the urine, and sometimes elevated liver enzymes and seizures. Symptoms can include, headache, swelling, abdominal pain, and nausea and vomiting. It usually develops in the last half of pregnancy or even postpartum in some women. In most cases, preeclampsia resolves after delivery. Although most women who develop preeclampsia have good maternal and fetal outcomes with modern medical care, it is still a serious disorder that increases risk of morbidity and mortality.
Why would these two conditions be related? The World Health Organization strongly urges calcium supplementation to prevent preeclampsia. Nutritional deficiencies in pregnancy may contribute. It is also hypothesized that in both conditions, higher levels of cell-free fetal DNA are present in the mother’s body. In both conditions, the maternal immune system responds differently to the foreign placenta than it does in normal pregnancies. There are changes in serotonin levels or serotonin receptor levels in both conditions as well.
If you have NVP that remains into the 2nd trimester, please talk to your OBGYN ask about hyperemesis and preeclampsia.