Effect of female body mass index on intrauterine insemination outcomes: a systematic review and meta-analysis

The prevalence of women with a raised body mass index (BMI) seeking assisted conception treatment is increasing. Findings of existing studies evaluating the effect of female BMI on intrauterine insemination (IUI) treatment outcomes remain inconsistent. This systematic review and meta-analysis evaluate the effect of female BMI on IUI treatment outcomes. Two authors independently conducted data extraction and assessed study quality. Risk ratios (RR) and 95% confidence intervals were calculated using the Mantel-Haenszel approach for dichotomous outcomes. 11 studies involving 23,145 IUI treatment events, comprising 21,211 cycles from 8 studies, and 1,934 participants in three studies, met the inclusion criteria for the meta-analysis. Two cohorts of women undergoing IUI treatment were compared - women with normal BMI < 25 kg/m(2 )were compared with a second cohort of women with a BMI category >= 25 kg/m(2). There was no statistically significant difference in live birth rate (LBR) (RR 1.06, 95% CI 0.86-1.307); clinical pregnancy rate (CPR) (RR 0.94, 95% CI 0.78-1.13); miscarriage (RR 0.92, 95% CI 0.31-2.74) or ectopic pregnancy rate (RR 2.20, 95% CI 0.78-6.23). Our meta-analysis showed that a raised female BMI did not affect IUI treatment outcomes. Nevertheless, weight loss counselling should be offered to women with a raised BMI undergoing IUI, to reduce the associated obstetric morbidity.