Birthing centers expert witness Susan Trezona, CNM, offers this article on her website:
Maternal Obesity Increases Risks
Mothers are considered overweight if their body-mass index, or BMI – a height-weight ratio – is between 25 and 30, and obese if their BMI is 30 or higher.
Overweight or obese women are two to three times as likely as normal-weight women to give birth to babies with either one or more serious defects, including the neural tube malformation known as spina bifida, omphalocele — in which intestines or other abdominal organs protrude through the navel — and malformations in the anal opening or urethra in boys, according to a study published in the August 2007 issue of the Archives of Pediatric and Adolescent Medicine.
Also, overweight or obese women have higher rates of miscarriage, gestational diabetes and hypertension, stillbirths and delivery of small infants. Additionally, it’s more difficult to monitor a pregnancy in an overweight or obese mother and therefore, the costs are also greater, Dr. Katz says. He also notes that there is an increased risk for Cesarean births in women with obesity.
It’s unclear why the public is still ill-informed about the risks of overweight or obesity in pregnancy. But Dr. Katz is adamant about one thing: “Women who are obese in pregnancy don’t need to gain additional weight,” he says.
Dr. Katz says he thinks part of the lack of awareness may stem from the long-time emphasis on women gaining enough weight during pregnancy. “But now, we’ve gone over the line,” he says. “The pendulum has swung in the other direction.”
Dr. Katz encourages women considering pregnancy to consult with their physician about the risks involved in conceiving while overweight. He recommends losing weight, adopting a more nutritious diet, and taking a daily multivitamin containing at least 1 milligram of folic acid. He also advises obese women planning to get pregnant to stabilize their weight loss program at least one month or one menstrual cycle before conception.