Mom's Low Cholesterol Tied to Preemie Births

Nutritional deficiencies and genetics may be to blame, researchers suggest.

By Serena Gordon
HealthDay Reporter
Monday, October 1, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

MONDAY, Oct. 1 (HealthDay News) -- While lower cholesterol is generally considered a good thing, new research suggests that very low cholesterol levels in pregnant women may harm the health of the fetus.

Expectant mothers whose total cholesterol levels were under 159 milligrams per deciliter (mg/dL) gave birth -- on average -- to babies weighing about one-third of a pound less than babies born to mothers whose cholesterol levels exceeded 159 mg/dL, the researchers found.

Additionally, 12.7 percent of white women with low cholesterol levels gave birth prematurely, compared to just five percent of those with higher cholesterol levels. No such association was found in black women, however.

"To our surprise, we found that white women with very low cholesterol also have a significant risk of having babies born prematurely," said Dr. Max Muenke, chief of medical genetics at the U.S. National Human Genome Research Institute in Bethesda, Md.

Results of the study are in the October issue of Pediatrics.

"At this point, it's not even clear if it's the low cholesterol itself, or another lipid," he said, adding that more research is needed to confirm these findings.

"This study intuitively makes some sense," said Dr. Robert Welch, chair and program director for obstetrics and gynecology at St. John Health's Providence Hospital in Southfield, Mich. "Cholesterol is a building block for membranes, hormones and proteins, so it makes sense that if you have low cholesterol, your baby won't have the substrate it needs to grow."

Each year, more than half a million babies are born prematurely in the United States, according to the March of Dimes. Medical advances have brought down the incidence rates for many diseases and conditions, but that's not been the case with premature or low birth weight babies.

In 1994, 11 percent of babies were born prematurely, and 7.3 percent were considered low birth weight. In 2004, those numbers were 12.5 percent and 8.1 percent, respectively. A preterm birth is one that occurs before 37 weeks, and a baby under five and a half pounds is considered to have a low birth weight.