Late in 2011, a study was published in the American Journal of Epidemiology that found an association between consumption of probiotic milk products and the reduced risk of developing preeclampsia, a serious pregnancy condition involving high blood pressure and high levels of protein in the urine. Preeclampsia is one of the leading causes of maternal death worldwide, estimated to affect between 2 and 8 percent of all pregnancies.
Because inflammation is an underlying feature of preeclampsia, and because diet and the gut microflora can contribute to inflammation throughout the body and have been suggested as having effects on blood pressure, researchers hypothesized that intake of food with probiotics might delay and reduce preeclampsia.
The analysis of over 33,000 pregnant women in Norway, in the Mother and Child Cohort Study, found that when the women who consumed at least 4.7 ounces of milk products containing probiotics during the first half of pregnancy their risk of developing preeclampsia, especially severe preeclampsia, was reduced. A weak dose-dependent association was found, meaning that the more probiotic milk the women consumed, the more benefit they experienced.
The study will have to be confirmed by follow-up with a randomized controlled trial using probiotics or probiotic food during pregnancy, but this preliminary study certainly adds to a large amount of evidence in support of the benefits of probiotics during pregnancy. Talk with your doctor about taking a probiotic if you are pregnant and think it would be beneficial for you.