SummaryIn this report we present an unusual case of a couple who achieved a twin pregnancy by intracytoplasmic sperm injection (ICSI) with a single immature oocyte retrieved. The oocyte was at metaphase I at 39 h post human chorionic gonadotrophin (hCG) administration, which is our standard ICSI time. Extended culture allowed the extrusion of the polar body, and sperm injection was performed at 43 h post-trigger. The fertilized egg underwent embryo biopsy on day 3 and preimplantation genetic assessment for three chromosomes (X, Y and 21). The embryo remained in culture until day 5. Later, the biopsy results reported a transferable embryo, which was replaced to the uterine cavity at blastocyst stage. Pregnancy test gave a positive β-hCG result, and the 6 weeks’ scan, performed to confirm the fetal heart, revealed the presence of one amniotic sac and two fetal heartbeats, which currently have been so far eventless and smooth, ongoing at 18 weeks of gestation.

中文翻译：

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单个卵母细胞胞浆内精子注射导致单个囊胚转移后单羊膜双胎妊娠：病例报告

摘要在本报告中，我们介绍了一对夫妇通过胞浆内单精子注射 (ICSI) 获得双胞胎妊娠的不寻常案例，并取回了一个未成熟的卵母细胞。在人绒毛膜促性腺激素 (hCG) 给药后 39 小时，卵母细胞处于中期 I，这是我们的标准 ICSI 时间。延长培养允许极体挤出，并在触发后 43 小时进行精子注射。受精卵在第 3 天进行了胚胎活检，并对三个染色体（X、Y 和 21）进行了植入前遗传评估。胚胎一直处于培养状态直到第 5 天。后来，活检结果报告了一个可移植的胚胎，该胚胎在囊胚阶段被替换到子宫腔中。妊娠试验 β-hCG 结果为阳性，并进行了 6 周的扫描以确认胎心，