Obesity and overweight are common conditions in the developed countries and they carry many health consequences, including some reproductive disorders. There is a very high prevalence of obese women in the infertile population and many studies have highlighted the link between obesity and infertility. A large proportion of infertile women have polycystic ovary syndrome (PCOS) which is also linked with increased risk of obesity and other metabolic anomalies. The association between obesity and/or PCOS and hyperinsulinaemia, hyper androgenism and abnormal secretion of other hormones, such as leptin, underlies many reproductive disorders observed in this population. It has been demonstrated that weight loss can improve the fertility of obese women through the recovery of spontaneous ovulation, whereas others will have improved response to ovarian stimulation in infertility treatment. Therefore, it is proposed that following the initial assessment of infertility and body mass index or other measurement of obesity, various weight management interventions, including diet, exercise or pharmacotherapeutic approaches, should be considered for overweight and obese infertile women.

Women with PCOS, particularly those with a high BMI, should be reviewed regularly with respect to IGT or NIDDM, as the frequency of impaired glycaemic control is high, and that the rate of conversion from normal glucose tolerance to IGT or NIDDM, or from IGT to NIDDM is substantial.

WANG, JIM X., MICHAEL J. DAVIES, AND ROBERT J. NORMAN. Obesity increases the risk of spontaneous abortion during infertility treatment. Obes Res. 2002;10: 551-554. Objective: This study examines the relationship between body mass and the risk of spontaneous abortion in a large cohort of patients who received infertility treatment. Research Methods and Procedures: This is a retrospective study using data on pregnancies (n ϭ 2349) achieved after treatment in a tertiary medical center from 1987 to 1999. One pregnancy per subject was included, and the subjects were stratified into five body mass groups based on body mass index (BMI): underweight, Ͻ18.5 kg/m 2 ; normal, 18.5 to 24.9 kg/m 2 ; overweight, 25 to 29.9 kg/m 2 ; obese, 30 to 34.9 kg/m 2 ; and very obese, Ն35 kg/m 2 . Logistical regression analysis was used. Results: The overall incidence of spontaneous abortion was 20% (476 of 2349). The effect of BMI on the risk of spontaneous abortion was significant after adjusting for several independent risk factors. Compared with the reference group (BMI 18.5 to 24.9 kg/m 2 ), underweight women had a similar risk of spontaneous abortion, whereas there was progressive increase of risk in overweight, obese, and very obese groups (p Ͻ 0.05, p Ͻ 0.01, and p Ͻ 0.001, respectively). Discussion: Of all known risk factors for spontaneous abortion, the control of obesity has great significance because it is noninvasive, potentially modifiable, possibly amenable to low cost, and self-manageable by patients. This study established a positive relationship between BMI and the risk of spontaneous abortion in women who became pregnant after assisted reproductive technology treatment.

The results of this study suggest that the higher risk of spontaneous abortion observed in women with PCOS is likely to be due to their high prevalence of obesity and the type of treatment they receive.