Obesity Increases the Risk of Spontaneous Abortion during Infertility Treatment

Abstract

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.

Increased body mass index negatively impacts blastocyst formation rate in normal responders undergoing in vitro fertilization

“…This trend is consistent with other studies examining the effect of BMI on pregnancy, live birth, and miscarriage rates which have found similar associations [9,11,20,29,30]. Rittenberg et al [30] reported a significantly lower live birth rate in patients with a BMI ≥25 kg/m 2 when compared to patients with a normal BMI (64 versus 81 %, p=0.005).…”

Optimal parameters for determining the LH surge in natural cyclefrozen-thawed embryo transfers

“…Wang et al also reported that the spontaneous abortion rates in women undergoing infertility treatment progressively increased with increasing BMI [18]. Thus, our findings that obesity was associated with lower implantation rates and higher spontaneous abortion rates are similar to those described in the literature [17][18][19][20][21]. It has been suggested that the adverse effects of obesity on IVF outcomes may be attributed to the alteration in the uterine environment [22,23].…”

“…Loveland et al showed that women with BMI > 25 kg/m 2 exhibited lower implantation and pregnancy rates and higher spontaneous abortion rate following IVF compared to women with [17]. Wang et al also reported that the spontaneous abortion rates in women undergoing infertility treatment progressively increased with increasing BMI [18]. Thus, our findings that obesity was associated with lower implantation rates and higher spontaneous abortion rates are similar to those described in the literature [17][18][19][20][21].…”

“…The correlation between BMI and IVF outcomes has been well investigated [17][18][19][20]. Loveland et al showed that women with BMI > 25 kg/m 2 exhibited lower implantation and pregnancy rates and higher spontaneous abortion rate following IVF compared to women with [17].…”

Obesity and Female Fertility: The Bridging Role of Leptin

“…The ongoing pregnancy rate and live birth rate is however consistently decreased especially due to an increase in miscarriages in women with obesity [56][57][58]. What should be verified?…”