Determining the cause of intrauterine fetal death in monochorionic twins: A case report

BackgroundDetermining the cause of intrauterine fetal death is essential for patients to manage their next pregnancy. However, in the majority of cases of fetal death, the cause remains unexplained despite comprehensive evaluation, especially in the cases of twins. Among twin pregnancies, conditions of monochorionic twinning, commonly regarded as monozygotic, are more complicated than dichorionic ones. Case summaryWe systematically evaluated the cause of fetal death for a Han Chinese woman with monochorionic twinning following in vitro fertilization/embryo transfer. Discrepant karyotypes were unexpectedly discovered between the twins. One fetus had an aneuploid male karyotype (46, XY), dup (9) (p24.3-q13), and the other had a normal female karyotype (46, XX). We considered that the male died of aberration of chromosome 9 and the female died of subsequent acute exsanguination through vascular anastomosis. ConclusionThis study demonstrated the importance of recognizing the presence of monochorionic dizygotic twinning and the challenges of clinical management for twins following in vitro fertilization/double embryo transfer.

Automated summary

This study systematically evaluated the cause of fetal death in a Han Chinese woman with monochorionic twinning following in vitro fertilization/embryo transfer. Discrepant karyotypes were discovered between the twins, with one fetus having an abnormal male karyotype (46, XY) and duplication (9) (p24.3-q13), and the other having a normal female karyotype (46, XX). The male fetus was considered to have died due to chromosome 9 aberration, while the female fetus died due to subsequent acute exsanguination through vascular anastomosis. This study highlights the importance of recognizing monochorionic dizygotic twinning and the challenges of clinical management for twins following IVF/double embryo transfer.