Low Cholesterol During Pregnancy: One Of The Causes of Premature Births?

Low cholesterol levels in women may prevent them from having heart disease. But, some emerging studies that suggest that, in some instances, having very low cholesterol levels may actually be one of the causes of premature births. For instance, a study performed at the National Human Genome Research Institute recently reported that pregnant women with very low total cholesterol levels might be at a higher risk for delivering their babies prematurely. Premature births can lead to a lot of consequences such as respiratory disease, cerebral palsy, and death.

For this study, a little under 1,100 women, ages 21 to 34, in South Carolina were examined during their second trimester over a 5-year period. These women were not diabetic and did not smoke. During this visit, blood was taken in order to evaluate their total cholesterol levels. These women were followed for the duration of their pregnancy.

The researchers found that women with total cholesterol levels lower than 159 mg/dL had up to a 21% increased incidence of delivering their baby prematurely. While this increase was especially evident in Caucasian women, low cholesterol levels did not appear to affect African Americans.

Additionally, babies delivered by African-American and Caucasian women with lower cholesterol levels had a slightly lower birth weight (a difference on the average of five ounces). Another interesting finding was that the babies delivered by women with the lowest cholesterol levels were born with heads of smaller circumference (microcephaly). No other birth defects were identified while this study was conducted.

Other studies have shown pregnant women with total cholesterol levels higher than 261 mg/dL were also at higher risk for delivering prematurely. In this study, roughly 12% of Caucasians and African-American mothers delivered their babies prematurely.

Cholesterol plays an important role in fetal development, and this study sheds some light on the importance of cholesterol, especially during pregnancy. Although high cholesterol levels have been proven to contribute to the development of conditions such as heart disease, very low cholesterol levels may have consequences, too.

More studies will be needed to further establish a connection between low cholesterol and premature delivery. One item that was not addressed during the study was the weight of the pregnant women, since poor nutritional intake may also influence cholesterol levels. Until more studies are performed, it is recommended that pregnant women follow a healthy, balanced diet and regularly consult with their healthcare provider.

_Sources:

Edison RJ, Berg K, Remaley A, et al. Adverse Birth Outcome Among Mothers With Low Serum Cholesterol. Pediatrics. 2007;120;723-733.