**3.1. Is there a need to treat endometriosis in patients undergoing IVF?**

In a meta-analysis (15)the chance of achieving pregnancy after IVF was significantly lower for patients with endometriosis (odds ratio, 0.56; 95% confidence interval, 0.44-0.70), as compared to those withtubal factor. They also reported decreased fertilization rates, implantation rates and in the number of oocytes retrieved.
