Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Department of Integrative Physiology and Biochemistry, University of Colorado at Boulder, Boulder, NV, United States.
Front Endocrinol (Lausanne). 2023 Sep 20;14:1188433. doi: 10.3389/fendo.2023.1188433. eCollection 2023.
ICSI (intracytoplasmic sperm injection) leads to a reduced male-to-female ratio at birth, whereas blastocyst transfer results in an increased male-to-female ratio. However, limited knowledge exists regarding the impact of these factors on the live birth rate for each gender. This study aimed to investigate the influence of patient characteristics and treatment parameters on the live birth rate for each gender, as well as the ultimate male-to-female ratio at birth in frozen-thawed embryo transfer (FET) cycles.
This retrospective cohort study involved a total of 28,376 FET cycles and 9,217 subsequent deliveries, spanning from January 2003 to December 2015. The study consisted of two parts. First, logistic regression models were constructed to determine the factors influencing the male-to-female ratio among babies born after FET. Second, we aimed to investigate the mechanisms underlying this sex ratio imbalance by analyzing data from all transfer cycles. Generalized estimated equations were employed to assess the impact of risk factors on rates of male and female live births separately.
ICSI resulted in a lower proportion of male offspring compared to fertilization (IVF) (50.1% vs. 53.7%, aOR: 0.87, 95% CI: 0.80-0.96). Conversely, blastocyst transfer yielded a higher proportion of male offspring than cleavage-stage embryo transfer (58.7% vs. 51.6%, aOR: 1.32, 95% CI: 1.17-1.48). Analysis of all cycles indicated that ICSI resulted in a reduced likelihood of male live birth in comparison to IVF (19.8% vs. 21.6%, aOR: 0.90, 95% CI: 0.83-0.97). However, the transfer of blastocysts rather than cleavage-stage embryos not only increased the chance of male live birth (26.9% vs. 20.2%, aOR: 1.70, 95% CI:1.56-1.85) but also facilitated female live birth (20.3% vs. 19.3%, aOR: 1.26, 95% CI: 1.15-1.39).
ICSI was associated with a reduction in the male-to-female sex ratio and a lower rate of male live births, while blastocyst transfer was associated with an increased male-to-female sex ratio at birth and a higher rate of male live births.
卵胞浆内单精子注射（ICSI）导致出生时的男女比例降低，而囊胚培养则导致男女比例增加。然而，对于这些因素对每个性别的活产率的影响，我们的了解有限。本研究旨在探讨患者特征和治疗参数对每个性别的活产率以及冷冻胚胎移植（FET）周期中出生时最终男女比例的影响。
这是一项回顾性队列研究，共纳入了 28376 个 FET 周期和 9217 次后续分娩，时间范围为 2003 年 1 月至 2015 年 12 月。研究分为两部分。首先，构建逻辑回归模型，以确定 FET 后婴儿性别比的影响因素。其次，我们旨在通过分析所有转移周期的数据来探讨这种性别比例失衡的机制。使用广义估计方程分别评估危险因素对男性和女性活产率的影响。
与受精（IVF）相比，ICSI 导致男性后代的比例较低（50.1%比 53.7%，aOR：0.87，95%CI：0.80-0.96）。相反，囊胚培养比卵裂期胚胎培养产生更高比例的男性后代（58.7%比 51.6%，aOR：1.32，95%CI：1.17-1.48）。对所有周期的分析表明，与 IVF 相比，ICSI 降低了男性活产的可能性（19.8%比 21.6%，aOR：0.90，95%CI：0.83-0.97）。然而，移植囊胚而不是卵裂期胚胎不仅增加了男性活产的机会（26.9%比 20.2%，aOR：1.70，95%CI：1.56-1.85），还促进了女性活产（20.3%比 19.3%，aOR：1.26，95%CI：1.15-1.39）。
ICSI 与男女比例降低和男性活产率降低相关，而囊胚培养与出生时男女比例增加和男性活产率升高相关。
