Weight Loss Interventions
It's been long known that morbid obesity can cause infertility. What most women don't know is that rapid weight loss can harm a woman's chances for having a healthy baby. This theory, subscribed to by a leading researcher named Richard Legro from the Penn State University College of Medicine's Department of Obstetrics and Gynecology in Hershey, Pennsylvania is said by Legro to be worthy of more research, since little is known about the topic. However, Legro states that extreme or sudden decreases in caloric intake combined with increased activity just before a woman conceives may have serious adverse effects. This includes women undergoing assisted reproductive techniques. Such sudden strenuous weight-loss techniques stress the reproductive system and could lead to a failure to conceive, warns Legro.
While the disruptions to the normal workings of the body can be assumed in the case of drastic weight loss, there is an additional concern for women trying to conceive. Many environmental pollutants are stored in body fat. This includes such toxins as DDT and organochlorine. When fat is burned through dramatic changes in lifestyle, Legro believes it's possible these pollutants are released into the bloodstream. These chemicals may have a dire effect on pregnancy, should one occur at this time.
Professor Legro was the lead author of the National Institutes of Health's (NIH) studies on pregnancy in women with PCOS (polycystic ovarian syndrome) who are obese. PCOS is one of the leading causes of infertility. Legro addressed the issue of extreme and sudden weight loss in women undergoing treatment for infertility at a recent conference called Updates in Infertility Treatment, held in Seville. The professor explained that the issue has never undergone a proper investigation using rigorous controlled clinical trials. "We don't know how many calories are needed, how long women should diet, or whether they should do it at all during infertility treatment."
Legro spoke of studies on women undergoing fertility treatments while on very low-calorie diets. In these studies, women lost 8.8% of their total body fat over the course of 6 weeks. The diets were stopped when women were found to have low numbers of oocyte, poor rates of fertilization, and low pregnancy rates. The professor also mentioned the way in which intensive exercise was found to lead to higher rates of implantation failure in in-vitro fertilization (IVF).
Legro says that it has been hard to achieve a follow-through on weight loss studies, since most of the participants, a full two-thirds, tend to drop out of the studies. "The weight-loss intervention providing the most bang for your buck is bariatric surgery where up to 40 per cent of body weight is lost on average after one year and is still 30 per cent less after 10 years. If you follow PCOS patients after bariatric surgery it effectively cures PCOS and improves insulin sensitivity but we don't know its effects on fecundity," concluded Legro.