Outcomes in in vitro fertilization (IVF) cycles which display dysynchronous follicular growth

Abstract

Diminished ovarian reserve can cause advanced follicular recruitment (dysynchrony) due to inappropriate rises of FSH during the luteal phase. Dysynchrony is considered poor prognosis. Previous data have shown that high dose estradiol during the preceding luteal phase can synchronize the follicular cohort. Though there is no precise definition of dysynchrony during in vitro fertilization cycles, it can be defined as one follicle significantly larger than the remaining cohort on stimulation day 6 (early), or when the two lead follicles reach maturity two days prior to the cohort reaching maturity (late). This study tried to determine: 1) the frequency of dysynchronous cycles, 2) to see if dysynchrony causes lower pregnancy and live-birth rates. Retrospective chart review of all couples undergoing in vitro fertilization with microdose agonist protocol. We compared two groups. Group A had early dysynchrony: 1 follicle ≥4 mm ahead of the cohort at first ultrasound (stimulation day 6); or late dysynchrony: 1–2 follicles reaching maturity (mean diameter 18 mm3) two or more days prior to the cohort reaching maturity. Group B: all other patients. The student t-test was used for continuous variables and Chi-Square for non-parametric data. 227 microdose GnRHa cycles were evaluated from 2003 through 2006. Dysynchrony occured in 1 out of 4 IVF cycles. There were no differences in average age of the female partner, primary diagnosis, antral follicle count, cycle day 3 estradiol, gonadotropin dose, cycle cancellation, or pregnancy rates among groups. Women displaying dysynchrony had slightly higher cycle day 3 FSH values; however, cycle day 3 FSH did not predict dysynchrony. Dysynchronous cycles had fewer eggs retrieved (7.4 ± 5.0, vs. 10.3 ± 7.1, P≤.05). Dysynchronous cycles showed trends for fewer grade 1–2 embryos available for transfer on post-retrieval day 3 (2.3 ± 2.5 vs. 3.0 ± 3.1, P=.08) and lower live-birth rates, compared to cycles without dysynchrony, (23% vs. 29%, P=0.29). In our population, dysynchrony occured in 1 of 4 women undergoing stimulation with the microdose GnRHa protocol for advanced maternal age or diminished ovarian reserve. Currently there is not enough evidence to say that dysynchrony leads to lower live-birth or pregnancy rates. Therefore, cycles displaying these characteristics do not need to be cancelled for dysynchrony alone. High-dose luteal estradiol to suppress FSH is not inidicated.