Natural cycle cryo-thaw transfer may improve pregnancy outcome

Abstract

Objective: To compare natural vs. hormone replacement treatment (HRT) for cryo-thaw embryo transfer cycles in patients with frozen embryos from previous ART. Design and Settings: Retrospective chart review of 164 patients (242 cycles) who underwent natural or HRT cryo-thaw embryo transfer between January 2002 and April 2005. Main Outcome Measures: Pregnancy rates per transfer in natural and HRT cryo-thaw cycles. Results: The pregnancy rate per transfer was higher with natural cycles (36.76% vs. 22.99%, P = 0.0298). There was no statistical difference in mean age, endometrial thickness, and average embryo quality in successful cycles. Mean endometrial thickness prior to transfer was greater in natural cycles (9.95 vs. 8.89 mm, P < 0.001). Mean serum estradiol levels were higher in the HRT group prior to transfer (526.1 vs. 103.8 pg/ml, P < 0.001), and were found to be lower in women who achieved pregnancy (337.1 vs. 433.3 pg/ml, P = 0.0136). Conclusion: Hormone replacement in preparation for cryo-thaw transfer of embryos was found to be associated with decreased pregnancy rates in comparison to natural cycle cryo-thaw transfer. Greater endometrial thickness was achieved with lower serum estradiol levels in patients undergoing natural cycles, suggesting Financial disclosure: none of the above authors had any financial interests with commercial companies.

A modified natural cycle results in higher live birth rate in vitrified-thawed embryo transfer for women with regular menstruation

“…In agreement with our findings, some previous studies observed superior outcomes in terms of implantation, clinical pregnancy, and lower miscarriage rates when natural cycles were used [Morozov et al 2007;Orvieto et al 2016;Xiao et al 2012]. Moreover, since FET during a natural cycle is less expensive and more patient-friendly, Peeraer et al [2015] recommended NC regimen as the treatment of choice for women with regular cycles undergoing FET.…”

“…For example, natural cycles with or without human chorionic gonadotropin (HCG) induced ovulation requires minimum medication and typically carried the least risk for adverse effects and is the least costly. Several groups have reported superior results for this regimen [Morozov et al 2007;Xiao et al 2012]. For the reason of convenience, artificial cycles are often applied to patients with regular menstrual intervals.…”

Preparation of endometrium for frozen embryo replacement cycles: a systematic review and meta-analysis

“…Luteal phase support was given in five studies [36,[40][41][42][43]; the ORs for clinical pregnancy and live birth rates were not significantly different (OR 1.32 (95 % CI 0.90-1.93; four studies) and 1.47 (95 % CI 0.72-3.03; two studies), respectively).…”

“…A total of eight studies, all being retrospective cohort studies [35,36,[38][39][40][41][42][43], making a total of 8762 ET cycles, were included.…”

Estrogen supplementation in art (a review)

“…[43] установили, что толщина эндометрия при переносе в естественном цикле (ЕЦ) выше (9,95 мм против 8,89 мм; p<0,001), а средний уровень эстради-ола ниже (103,8 пг/мл против 526,1 пг/мл; p<0,001) по сравнению с ЗГТ. Частота наступления беремен-ности также оказалась выше после переноса размо-роженных эмбрионов в ЕЦ (36,76% против 22,99%; p=0,0298).…”