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Obesity Increases the Risk of Some Birth Defects

Obesity Increases the Risk of Some Birth Defects


Many of us, men and women alike, probably have a few extra pounds that we would like to shed, and we are well aware, hopefully, of the importance of maintaining a healthy weight. But for women who are pregnant or planning on becoming pregnant, the dangers posed by those extra pounds can affect more than just their own health.

Medical researchers have discovered that women who are overweight prior to becoming pregnant experience a greater risk of having children with birth defects. While previous studies have shown a connection between pre-pregnancy obesity and birth defects involving the brain and spinal cord – such as spina bifida – new research has revealed that maternal obesity may be linked to a broader range of birth defects than previously realized.

The Current Study

Researchers interviewed nearly 15,000 women who had given birth between 1997 and 2002. Of these, 10,249 women had had babies with birth abnormalities while 4,065 women had babies that were physically healthy. Researchers collected and compared the pre-pregnancy height and weight of the women and calculated that 2,312 had been obese. The results indicated that, among babies born to obese mothers, 4 percent could be expected to have major birth defects, as compared to only 3 percent of infants born to women of average weight.

Of the sixteen different birth defects researchers observed in the study, seven were found to be more common in infants of obese mothers:

  • Spina bifida
  • Heart defects
  • Deformity in the anal opening (anorectal atresia)
  • Abnormally positioned male urethral opening (hypospadias)
  • Small or missing limbs
  • Diaphragmatic hernia
  • Protrusion of the intestines or other abdominal organs through the navel (omphalocele)

Cause and Effect?

Researchers are quick to point out that their studies do not identify a direct causal relationship between obesity and birth defects, and that the overall risk posed by maternal obesity to an unborn child is quite small. They hasten to add that other factors, such as dieting and undiagnosed diabetes, may also contribute to birth abnormalities. The studies simply indicate that in cases in which babies were born with a particular birth defect, the mother was more likely to have been obese prior to pregnancy.

So What's the Skinny?

In short, authors of the study assert that the results support the importance of maintaining a healthy weight, and they advise women who are overweight to avoid fad and crash diets if they are pregnant or thinking of becoming pregnant. If a woman becomes pregnant and is overweight, then losing some of the extra pounds is a good idea, but it should be done carefully and with a healthy diet.

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