This is a sensitive topic to broach for obvious reasons, but once again physical health and an active lifestyle become more than just a handy convenience or a lifestyle choice. Maternal obesity can cause numerous problems, and is one of the most overlooked adverse prenatal conditions. Obesity during pregnancy is associated with late fetal death, ante partum stillbirth, early neonatal death, large for gestational age infants, birth defects, preeclampsia, hypertensive and thromboem-bolic disease, heart defects, cleft palates, hydrocephaly (a buildup of cerebrospinal fluid in the brain), and spina bifida, as well as other birth defects. (Cnattingius et al., 1998; Anderson et al., 2005; Cedergren, 2004; Rubin, 2/11/09) For the mom, it can also cause problems, such as unplanned C-section, excessive bleeding after delivery, wound infection, or delivery problems and anesthesia complications. (Rubin, 2-11-09)

Obesity-related Birth Defects
The increased risk for serious birth defects may be small when compared to the overall population; 4 percent versus 3 percent among healthy weight mothers. But this means that an extra one out of every 100 babies born suffers with a birth defect because of his or her mother’s weight problems. (add ref) Obesity-related birth defects account for a significant number of all birth defects, making this issue comparable with substance abuse as a risk factor for prenatal harm. The stakes are increased even more when a mother has diabetes. Uncontrolled diabetes during pregnancy can result in a threefold increase in birth defects and maternal health problems. (Kitzmiller et al., 1996; Roland et al., 2005)

The Long-Term Effects of a Mother’s Obesity During Pregnancy & the Risks it Poses to the Baby
Aside from physical deformations or pregnancy problems, maternal obesity and the lifestyle habits that tend to accompany it can increase the risk of a child’s own obesity problems later on. When women gain more than the recommended weight during pregnancy (25 to 35 pounds for healthy women), their kids are 48% more likely to be overweight later on. A diet that is high in fat during pregnancy has been shown to reshape the brain of offspring in rats, setting them up for a lifelong risk of obesity. Nutritional deficiencies in a mother’s diet can also cause problems, potentially leading to infants that are shyer, fussier, and less sociable. (Laber-Warren, 2009)

Other studies have found that sons of obese mother mice grew up fat, anxious, and with signs of brain inflammation. They exhibit increased levels of Interleukin-1, a chemical which previous studies have shown to impair learning and memory. Furthermore, obesity in these mice persisted into adulthood even though they were switched to low-fat diets once weaned, an example of how a mother’s poor diet and exercise habits can result in a lifetime of weight struggles for her offspring. (HesmanSaey, 2009)

Similar lifelong threats to a child’s wellbeing occur when it comes to the risk of diabetes. Babies born when their mothers had already developed obesity-related diabetes were 4-times as likely to develop the condition themselves, and also averaged half-a-pound more per square foot of skin than siblings born before their mother developed diabetes. (Dabelea et al., 2000) And if a mother develops gestational diabetes, it makes any future daughters of hers nearly 8-times as likely to develop it themselves during pregnancy – increasing the health burden with each subsequent generation. (Egeland, Skjaevren & Irgens, 2000) Gestational diabetes, too, is largely a result of poor health habits and the current obesity epidemic. All told, this amounts to a serious, lifelong health risk for children who are born to overweight or obese mothers.

It’s been found that a fetus “tastes” a mothers diet through the amniotic fluid, and therefore, this predispositions the baby towards a tendency for either healthy or unhealthy foods later on. (Greene, 2009) This is consistent with other research on animals, showing that prenatal environments somehow tell a baby “what to eat” when it emerges from the womb. (Milius, 2009) And as discussed earlier, so-called obesity genes can be flipped either off or on, and the disposition of those genes carried from mother to child, based on a mothers lifestyle habits. (Wolffe & Matsky, 1999; USA Today, 9-9-08; PBS, 9-22-08)

Obesity Prevalence During Pregnancy
One study showed that the mean prevalence for obesity during pregnancy was 21.9 percent, with another 13.1 percent of mothers being overweight. (CDC, 12-14-07) This puts as many as 1 in 3 babies at risk for adverse birth outcomes.