Department of Maternal and Child Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China.
Department of Vascular anomalies and Interventional Radiology, Qilu Children's Hospital of Shandong University, Jinan, 250022, Shandong, China.
Reprod Sci. 2021 May;28(5):1267-1276. doi: 10.1007/s43032-020-00323-2. Epub 2020 Oct 1.
The purpose of this study is to identify that the advantages of frozen embryos are not evident in ovulatory women or women with non-polycystic ovary syndrome (non-PCOS) by meta-analysis. An exhaustive literature search of PubMed (MEDLINE), Embase, and Cochrane Library databases was performed until March 20, 2020 (limited to articles published in English). We included randomized clinical trials comparing the results of frozen and fresh embryo transfers. The primary outcomes were live birth rate and birth weight. The fixed effect model was used when a significant heterogeneity was observed. Otherwise, a random effect model was used. In 511 identified studies, 4 were eligible and were included in this review. There was no difference in live birth rate, singleton birth weight, clinical pregnancy, ongoing pregnancy, gestational diabetes, and gestational hypertension between frozen and fresh embryos. In frozen embryos, the relative risk of moderate or severe ovarian hyperstimulation syndrome (OHSS) was lower, the incidence rate of pre-eclampsia higher, and the standardized mean difference of twin birth weight higher than in fresh embryos. There is no significant difference between frozen embryo transfer (FET) and fresh embryo transfer in ovulatory women or women with non-PCOS. We recommend that the transfer depends on the actual situation in the patient in clinical practice, rather than the "freeze all" policy and thawing FET.
本研究旨在通过荟萃分析确定，对于排卵正常或非多囊卵巢综合征（non-PCOS）的女性，冷冻胚胎并无明显优势。检索了 PubMed（MEDLINE）、Embase 和 Cochrane Library 数据库，检索时间截至 2020 年 3 月 20 日（仅限于发表的英文文章）。我们纳入了比较冷冻胚胎与新鲜胚胎移植结果的随机临床试验。主要结局为活产率和出生体重。当存在显著异质性时，采用固定效应模型；否则，采用随机效应模型。在 511 项已确定的研究中，有 4 项符合纳入标准，并纳入本综述。冷冻胚胎与新鲜胚胎的活产率、单胎出生体重、临床妊娠、持续妊娠、妊娠期糖尿病和妊娠期高血压无差异。与新鲜胚胎相比，冷冻胚胎的中重度卵巢过度刺激综合征（OHSS）相对风险较低，子痫前期发生率较高，双胞胎出生体重的标准化均数差较高。对于排卵正常或非多囊卵巢综合征的女性，冷冻胚胎移植（FET）与新鲜胚胎移植无显著差异。我们建议在临床实践中，根据患者的实际情况决定移植方式，而不是采用“全部冷冻”策略和解冻 FET。
