124. van der Steeg JW, Steures P

van der Steeg JW, Steures P, Eijkemans MJ, Habbema JD, Hompes PG, Burggraaff JM, Oosterhuis GJ, Bossuyt PM, van der Veen F and Mol BW.

Obesity affects spontaneous pregnancy chances in subfertile, ovulatory women. Hum Reprod 2008:23:324-8.

BACKGROUND:
Obesity is increasing rapidly among women all over the world. Obesity is a known risk factor for subfertility due to anovulation, but it is unknown whether obesity also affects spontaneous pregnancy chances in subfertile, ovulatory women.

 
METHODS:
We evaluated whether obesity affected the chance of a spontaneous pregnancy in a prospectively assembled cohort of 3029 consecutive subfertile couples. Women had to be ovulatory and had to have at least one patent tube, whereas men had to have a normal semen analysis. Time to spontaneous ongoing pregnancy within 12 months was the primary endpoint.

 
RESULTS:
The probability of a spontaneous pregnancy declined linearly with a body mass index (BMI) over 29 kg/m(2). Corrected for possible related factors, women with a high BMI had a 4% lower pregnancy rate per kg/m(2) increase [hazard ratio: 0.96 (95% CI 0.91-0.99)].

 
CONCLUSIONS:
These results indicate that obesity is associated with lower pregnancy rates in subfertile ovulatory women.