Effect of endometriosis on in vitro fertilization.

OBJECTIVE: To investigate the IVF outcome for patients with endometriosis.
DESIGN: Meta-analysis.
SETTING: Academic research center. PATIENT(S): A MEDLINE search and review of the literature were performed. Patients were classified by level of endometriosis, and controls were classified according to the indication for IVF. INTERVENTION(S): Bivariate analysis and multivariate logistic regression was used to estimate overall effect and control for confounding. MAIN OUTCOME MEASURE(S): Pregnancy rates, fertilization rate, implantation rates, and numbers of oocytes retrieved. RESULT(S): Twenty-two published studies were included in the overall analysis. The chance of achieving pregnancy was significantly lower for endometriosis patients (odds ratio, 0.56; 95% confidence interval, 0.44-0.70) when compared with tubal factor controls. Multivariate analysis also demonstrated a decrease in fertilization and implantation rates, and a significant decrease in the number of oocytes retrieved for endometriosis patients. Pregnancy rates for women with severe endometriosis were significantly lower than for women with mild disease (odds ratio, 0.60; 95% confidence interval, 0.42-0.87). CONCLUSION(S): Patients with endometriosis-associated infertility undergoing IVF respond with significantly decreased levels of all markers of reproductive process, resulting in a pregnancy rate that is almost one half that of women with other indications for IVF. These data suggest that the effect of endometriosis is not exclusively on the receptivity of the endometrium but also on the development of the oocyte and embryo.