High Body Fat Linked to Poor Pregnancy Results

Women whose body mass index (MBI) indicates that they are obese before or in the early stages of pregnancy face a much higher risk of stillbirth and infant death, compared to women of a healthy weight, according to a recent study.

The study, which was published in the Journal of the American Medical Association (JAMA), found that even small increases past a healthy maternal BMI was linked to a higher risk of fetal death, stillbirth, neonatal (newborn) death, perinatal (immediately before birth) death, and infant death due to complication.

According to the study, researchers conducted a comprehensive review of 38 studies that measured maternal BMI and the risks of pregnancy complications among mothers. The studies included 10,147 fetal deaths, 16,273 stillbirths, 4,311 perinatal deaths, 11,294 neonatal deaths and 4,983 infant deaths.

Even after adjusting for extraneous factors which would influence the risk of adverse birth complications, the researchers were able to determine that women with a maternal BMI over 40 (severely obese) faced a nearly three-fold increase in risk of the aforementioned poor pregnancy outcomes, compared to women with a BMI of 20 -- a BMI of 18.5 to 25 being deemed healthy or "normal."

Although the study only establishes an association between unhealthy maternal BMIs and poor pregnancy outcomes, previous studies have linked high maternal BMIs to increased risk of children developing diabetes and cardiovascular problems later in life, which may be in-part due to genetic disposition.

A more recent study has even linked paternal BMI to children facing an increased risk of developing autism, indicating that obesity -- or the causes of obesity -- may be tied to interference with healthy gene expression.

The most recent study was published in JAMA on April 15.