In vitro fertilization in normoresponder patients with endometriomas: comparison with basal simple ovarian cysts.

Objective: To investigate whether the space-occupying effect of an endometrioma, rather than endometriosis itself, affects results in in vitro fertilization (IVF) using women with simple ovarian cysts as the control group.

Methods: 85 normoresponder patients with endometriomas of 10-50 mm who underwent IVF treatment directly without initial removal were compared with 83 normoresponder patients with simple ovarian cysts of 10-35 mm detected at the beginning of stimulation and initiated treatment without aspiration.

Results: Gonadotropin consumption was higher in the endometrioma group (3,013 vs. 2,451 IU; p = 0.001), although significantly fewer numbers of oocytes were retrieved (13.9 vs. 16.4; p = 0.03). However, oocyte maturation rates were similar. The transferred grade I embryos ratio was evaluated and found to be better in the cyst group (79.7 vs. 70.7%; p = 0.03). Consequently, the implantation rate was found to be significantly higher in the cyst group (28 vs. 19%; p = 0.02), although pregnancy and ongoing pregnancy rates were similar.

Conclusion: The presence of an endometriotic cyst during the IVF cycle was demonstrated to be associated with a lower embryo quality and implantation rate, although pregnancy success was unaffected. This adverse effect is suggested to be the result of the disease itself, not the presence of a cystic mass.