It has long been known that being overweight during pregnancy could lead to medical problems during the pregnancy such as high blood pressure and diabetes. In addition, being overweight during pregnancy may lead to increased birth defects. Women have been encouraged to achieve a healthy weight before becoming pregnant and to try to maintain a healthy lifestyle during their pregnancy to avoid these complications. It appears that achieving a healthy weight before pregnancy could also be important for the development of the baby.
A recent study in the British Medical Journal looked at more than 1.2 million births in Sweden over a period of fourteen years. The results not only showed that a higher weight before you get pregnant could lead to birth defects, but that higher weights are associated with even higher risks of these defects. The development of a baby’s organs such as the heart and brain occurs at about 8 weeks of pregnancy, a time at which many women may not even realize that they are pregnant. A normal weight before pregnancy seems to be the key to decreasing the risks of these birth defects.
In this study, researchers looked specifically at risk of defects associated with body mass index or BMI, a calculation that relates body weight to height that is commonly used to asses the degree a person is over or underweight for their height. They divided women in to groups of underweight (BMI <18.5), normal weight (BMI 18.5 to <25), overweight (BMI 25 to <30), obesity class I (BMI 30 to <35), obesity class II (BMI 35 to <40), and obesity class III (BMI ≥40). Women with a BMI >40 were found to be highest risk of having a baby with birth defects of several major organ systems, including the spine, brain, heart, digestive system, genital organs, and limbs. There was an almost doubled risk of problems with development of the spinal cord and brain (neural tube defects) in women who had BMI >40. Similar increased risks of defects in the babies of women with increasing BMI were seen. Women with a BMI >40 were at most risk of having a child with birth defects.
Weight alone is not the only factor that contributes to the health of a pregnancy and baby, but achieving a normal weight will decrease the risk of high blood pressure and diabetes of pregnancy and birth defects. Now, more than ever, discussion of healthy eating and exercise habits to achieve a healthy weight is important when discussing a woman’s desire to get pregnant; being a normal weight before pregnancy will increase the likelihood of a healthy pregnancy and lower the risk of birth defects. If you have questions on how we can help, please contact us!