Low Vitamin D Levels During Pregnancy Increase the Risk of Preeclampsia

The levels of vitamin D in expectant moms help predict the risk of developing severe preeclampsia, a life threatening disorder, claims a new finding.

The study, led by researchers at the University of Pittsburgh Graduate School of Public Health, states that pregnant women with low levels of Vitamin D in the first 26 weeks, have the risk of developing preeclampsia. Based on the analysis of blood samples of pregnant women, the study states that adequate levels of Vitamin D were linked with 40 percent reduced risk of severe preeclampsia. On the other hand, no similar association was noticed between levels of vitamin D and mild preeclampsia.

Preeclampsia occurs in the second half of the pregnancy and is marked by the presence of abnormally high blood pressure and high levels of protein in the urine. Due to this women have swelling in their hands, feet and legs. They also suffer from severe headaches and vision problems. When this condition is left untreated it leads to eclampsia, a serious life-threatening disorder for both the mother and the baby. This condition affects at least 5 to 8 percent of all pregnant women.

In the current study, blood samples of 700 pregnant women were collected who later developed preeclampsia. The status of vitamin D was examined in the blood samples in order to predict the risk of developing preeclampsia.

"For decades, vitamin D was known as a nutrient that was important only for bone health," said Lisa Bodnar, Ph.D., M.P.H., R.D., associate professor in Pitt Public Health's Department of Epidemiology. "Over the past 10 to 15 years, scientists have learned that vitamin D has diverse functions in the body beyond maintaining the skeleton, including actions that may be important for maintaining a healthy pregnancy."

The team also studied the blood samples of 3,000 mothers who did not have preeclampsia. The blood samples were collected during 1959-1965 from 12 different U.S. sites which were a part of the Collaborative Perinatal Project. Even decades later the researchers were able to test for vitamin D levels in the blood samples as the samples were well preserved.

The researchers controlled certain key factors that affect the status of Vitamin D in women. This included pre-pregnancy body mass index, race, smoking, diet, exposure to sunlight, physical activity and number of previous pregnancies.

Regardless of the vitamin D status, it was seen that the overall risk of preeclampsia was 0.6 percent, according to the sample study.

"Scientists believe that severe preeclampsia and mild preeclampsia have different root causes," said senior author Mark A. Klebanoff. "Severe preeclampsia poses much higher health risks to the mother and child, so linking it with a factor that we can easily treat, like vitamin D deficiency, holds great potential."

 The team says further studies are needed if the findings are constant even in modern samples of pregnant women.

Earlier, a study reported in the journal BMJ showed that preeclampsia occurs due to the deficiency of an amino acid, L-arginine. This amino acid helps in regulating the blood flow during pregnancy.

The finding was reported in the journal Epidemiology.