Mothers who give birth to babies with some kind of structural birth defect, such as missing arms and/or legs, malformed hearts and badly developed spinal cords, are more likely to have been obese before they became pregnant, compared to mothers who were not obese before their pregnancy, says an article in
The article states that obese/overweight women have a higher risk of developing chronic diseases, having problems with fertility, experiencing complications during pregnancy and having irregular menstrual periods. In 2004, 51% of women aged 20-39 in the USA were overweight/obese.
D. Kim Waller, Ph.D., University of Texas, Houston, and team interviewed 10,249 women in eight states. All their infants were born with birth defects during the period 1997-2002. They were all contacted from 6 weeks to 24 months after their babies were born and asked for their height and weight before pregnancy. Other medical information as well as details on demography were requested. These women were compared to 4,065 others whose babies were born without defects during the same period.
The following birth defects were associated with a higher chance that the mother was obese before pregnancy:
— Spina bifida, (the spinal cord is not covered – this causes problems with mobility as well as incontinence)
— Heart defects
— Anorectal atresia (the anal opening is malformed)
— Hypospadias (when the urethra opens on the underside instead of the end of the penis)
— Small or missing toes, fingers arms or legs
— Diaphragmatic hernia, or an opening in the diaphragm that allows abdominal organs to move into the chest cavity and may cause lungs to be underdeveloped
— Omphalocele (the intestines or other abdominal organs protrude out through the navel)
The researchers added “The reasons for an association between maternal obesity and a spectrum of structural birth defects are unknown. Both animal studies and human studies provide substantial evidence that alterations in glycemic control are responsible for an increased risk of a range of structural birth defects among women who have diabetes prior to becoming pregnant. Thus, a similar mechanism to that occurring in women with diabetes may be responsible for the associations observed between maternal obesity and specific categories of birth defects.” Women with type 2 diabetes were excluded from the study, and when the analysis was performed also excluding women with gestational diabetes, the results were similar. However, undiagnosed cases of type 2 or gestational diabetes may have affected the results. Our study supports previous evidence as well as provides new evidence for the associations between maternal obesity and particular categories of birth defects,” the authors conclude. “Future inquiries are needed to unravel the underlying reasons for these associations.”
Arch Pediatr Adolesc Med. 2007;161(8):745-750
Written by: Christian Nordqvist