Effect of starting time of ovarian stimulation on outcomes of in vitro fertilization in women with endometriosis

Objective To investigate the effect of appropriate starting time of gonadotropin (Gn) in modified prolonged protocol on outcomes of in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) in women with endometriosis (EMS). Methods A total of 98 cycles from infertile patients who underwent IVF/ICSI were retrospectively analyzed. The patients were divided into group A (modified prolonged protocol, EMS, n=44), group B (modified prolonged protocol, non-EMS, n=21) and group C (regular prolonged protocol, EMS, n=33). The difference of clinic outcomes was compared and analyzed among the different groups. Results 1) The total dosage of Gn used was lower and the fertilization rate was higher in group A [(2 330.4±747.8) IU, 77.6%]than in group B [(3 338.7±1 341.5) IU, 65.8%], the differences were statistically significant (P 0.05). 2) The initial dosage and total dosage of Gn used in group A [(192.0±35.3) IU, (2 330.4±747.8) IU] was higher than that in group C [(228.8±48.9) IU, (2 828.5±1 129.0) IU], the difference was statistically significant (P 0.05). Conclusion It is a cost-effective controlled ovarian hyperstimulation (COH) protocol for infertile patients with EMS, because the modified prolonged protocol can reduce the dosage of Gn used without affecting the clinical results through monitoring E2 level. Key words: Modified prolonged protocol; Starting time of gonadotropin; Serum E2 level; Endometriosis