Term pregnancy and live birth subsequent to immediate uterine transfer of sperm microinjected oocyte in a natural cycle

Abstract

It has been reported that it is possible to achieve a pregnancy after immediate uterine transfer of oocyte and sperm, before fertilization and cleavage were known to have occurred; there is an enormous amount of work about the optimal timing of embryo transfer, with no conclusive evidence of a gold standard satisfying patient age, endometrial receptivity, hormonal levels and embryological parameters. We hereby report a case of one 35-year-old nulligravid woman with longstanding tubal factor infertility and 3 previous failed ICSI cycles, treated with ICSI and immediate transfer of the oocyte microinjected with a spermatozoon in a natural cycle. A single oocyte was retrieved, injected with a spermatozoon and transferred 40 min after injection, resulting in an uneventful pregnancy and delivery of a healthy female infant weighing 3320 g at 40 weeks’ estimated gestational age. This case, certainly novel, should be interpreted with caution. Whether confirmed for efficacy and safeness in appropriate controlled clinical trials, our present observation could offer a simple, practical and cost-effective approach in ART programs in selected patients.

Chinese abstract

据报道称，在卵母细胞发生受精和卵裂前即刻将卵母细胞和精子植入宫腔获得妊娠是可能实现的；考虑到患者的年龄、子宫内膜容受性、激素水平及胚胎学参数而无法找到符合这一金标准的有力证据，因此关于胚胎移植最佳时期的选择仍需要进行大量的研究工作。而我们的病案中报道了一份病例：35岁女性，长期输卵管因素不孕，先前卵泡浆内单精子注射（ICSI）3个周期失败，本次在自然周期中行ICSI后立即将单精子注射后的卵母细胞植入宫腔。植入40分钟后单个卵母细胞成功获卵，成功妊娠并于足月（40周）顺利分娩一健康女婴，体重3320克。该报道毋庸置疑是创新的，但解读时应慎重。无论在适当的临床控制试验中是否能证明该技术安全有效，我们在现有的观察性研究中至少可以为实施辅助生殖技术中某些特定的病人提供简单、有效、性价比高的方法。

• ICSI
• immediate transfer
• natural cycle
• poor responder

Declaration of interest

The authors report no conflicts of interest.

Ethical Approval: For this type of study formal consent is not required. This article does not contain any studies with animals performed by any of the authors. Informed consent was obtained from all individual participants included in the study.