Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
JAMA. 2021 Jan 12;325(2):156-163. doi: 10.1001/jama.2020.23718.
In in vitro fertilization cycles using autologous oocytes, data have demonstrated higher live birth rates following cryopreserved-thawed embryo transfers compared with fresh embryo transfers. It remains unknown if this association exists in cycles using freshly retrieved donor oocytes.
To test the hypothesis that in freshly retrieved donor oocyte cycles, a fresh embryo transfer is more likely to result in a live birth compared with a cryopreserved-thawed embryo transfer.
DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study using national data collected from the Society for Assisted Reproductive Technology for 33 863 recipients undergoing fresh donor oocyte cycles in the US between January 1, 2014 and December 31, 2017.
Fresh embryo transfer and cryopreserved-thawed embryo transfer.
The primary outcome was live birth rate; secondary outcomes were clinical pregnancy rate and miscarriage rate. Analyses were adjusted for donor age, day of embryo transfer, use of a gestational carrier, and assisted hatching.
Recipients of fresh and cryopreserved-thawed embryos had comparable median age (42.0 [interquartile range {IQR}, 37.0-44.0] years vs 42.0 [IQR, 36.0-45.0] years), gravidity (1 [IQR, 0-2] vs 1 [IQR, 0-3]), parity (0 [IQR, 0-1] vs 1 [IQR, 0-1]), and body mass index (24.5 [IQR, 21.9-28.7] vs 24.4 [IQR, 21.6-28.7]). Of a total of 33 863 recipients who underwent 51 942 fresh donor oocyte cycles, there were 15 308 (29.5%) fresh embryo transfer cycles and 36 634 (70.5%) cryopreserved-thawed embryo transfer cycles. Blastocysts were transferred in 92.4% of fresh embryo transfer cycles and 96.5% of cryopreserved-thawed embryo transfer cycles, with no significant difference in the mean number of embryos transferred. Live birth rate following fresh embryo transfer vs cryopreserved-thawed embryo transfer was 56.6% vs 44.0% (absolute difference, 12.6% [95% CI, 11.7%-13.5%]; adjusted relative risk [aRR], 1.42 [95% CI, 1.39-1.46]). Clinical pregnancy rates were 66.7% vs 54.2%, respectively (absolute difference, 12.5% [95% CI, 11.6%-13.4%]; aRR, 1.34; [95% CI, 1.31-1.37]). Miscarriage rates were 9.3% vs 9.4%, respectively (absolute difference, 0.2% [95% CI, -0.4% to 0.7%]); aRR, 0.98 [95% CI, 0.91-1.07]).
In this retrospective cohort study of women undergoing assisted reproduction using freshly retrieved donor oocytes, the use of fresh embryo transfers compared with cryopreserved-thawed embryo transfers was associated with a higher live birth rate. However, interpretation of the findings is limited by the potential for selection and confounding bias.
在使用自体卵子的体外受精周期中，与新鲜胚胎移植相比，冷冻-解冻胚胎移植后的活产率更高。目前尚不清楚在使用新鲜获取的供体卵子的周期中是否存在这种关联。
检验以下假设，即在新鲜获取的供体卵子周期中，与冷冻-解冻胚胎移植相比，新鲜胚胎移植更有可能导致活产。
设计、地点和参与者：使用美国生殖技术协会在 2014 年 1 月 1 日至 2017 年 12 月 31 日期间收集的全国数据进行的回顾性队列研究，纳入了 33863 名接受新鲜供体卵子周期的接受者。
新鲜胚胎移植和冷冻-解冻胚胎移植。
主要结局是活产率；次要结局是临床妊娠率和流产率。分析调整了供体年龄、胚胎移植日、使用代孕者和辅助孵化。
新鲜和冷冻-解冻胚胎的接受者中位年龄相当（42.0 [四分位距 {IQR}，37.0-44.0] 岁 vs 42.0 [IQR，36.0-45.0] 岁），孕次（1 [IQR，0-2] vs 1 [IQR，0-3]），产次（0 [IQR，0-1] vs 1 [IQR，0-1]）和体重指数（24.5 [IQR，21.9-28.7] vs 24.4 [IQR，21.6-28.7]）。在总共 33863 名接受 51942 个新鲜供体卵子周期的接受者中，有 15308 个（29.5%）新鲜胚胎移植周期和 36634 个（70.5%）冷冻-解冻胚胎移植周期。在新鲜胚胎移植周期中，92.4%的周期中移植了囊胚，在冷冻-解冻胚胎移植周期中，96.5%的周期中移植了囊胚，转移的胚胎数量没有显著差异。新鲜胚胎移植后活产率为 56.6%，冷冻-解冻胚胎移植后活产率为 44.0%（绝对差异，12.6% [95%CI，11.7%-13.5%]；调整后的相对风险 [aRR]，1.42 [95%CI，1.39-1.46]）。临床妊娠率分别为 66.7%和 54.2%（绝对差异，12.5% [95%CI，11.6%-13.4%]；aRR，1.34 [95%CI，1.31-1.37]）。流产率分别为 9.3%和 9.4%（绝对差异，0.2% [95%CI，-0.4%至 0.7%]；aRR，0.98 [95%CI，0.91-1.07]）。
在这项使用新鲜获取的供体卵子进行辅助生殖的女性回顾性队列研究中，与冷冻-解冻胚胎移植相比，使用新鲜胚胎移植与更高的活产率相关。然而，由于存在选择和混杂偏倚的潜在风险，对研究结果的解释受到限制。
