Outcome of ICSI pregnancies with spontaneous loss of a co-twin compared with singleton ICSI pregnancies: Single center experience.

AIM: To compare the outcome of intracytoplasmic sperm injection (ICSI) pregnancies complicated by spontaneous loss of a dichorionic co-twin with that of singleton ICSI pregnancies. METHODS: The study group included dichorionic ICSI pregnancies with co-twin loss (n = 33) and the control group included ICSI pregnancies with a singleton from the beginning (n = 327). Primary outcome measures were obstetric complications, including preterm delivery, newborn small for gestational age, gestational diabetes, gestational hypertensive disorders and abruptio placenta; admission to neonatal intensive care unit (NICU) and perinatal mortality observed in the study and control groups. Statistical analysis was performed using spss for Windows, version 22.0. RESULTS: In the study group, there were 26 cases of first trimester (early) and 7 cases of second or third trimester (late) co-twin losses. Mean gestational age at delivery and mean birth weight were significantly lower in the whole study group compared to control (P < 0.05). Preterm delivery and NICU admission rates were significantly higher in the whole study group, compared to control (39.3% vs 14.6% and 36.36% vs 11.69% respectively, P < 0.05), but did not show significant difference between early loss subgroup and control (P > 0.05). Preterm delivery rate was significantly higher in the late loss subgroup compared to the early loss subgroup (85.71% vs 26.92% P < 0.05). CONCLUSION: Loss of a co-twin in dichorionic ICSI pregnancies is associated with increased risk of preterm birth. This risk is significantly higher in cases with late loss compared to the early loss cases.

Fetal sex discordance in a monochorionic twin pregnancy following intracytoplasmic sperm injection: A case report of chimerism and review of the literature.

A 39-year-old woman who became pregnant with twins after an intracytoplasmic sperm injection was referred at the ninth gestational week to determine chorionicity. Ultrasonographic examination showed a monochorionic diamniotic twin pregnancy. First trimester nuchal translucency measurements of the fetuses were 1.6 and 2.7 mm. A non-invasive prenatal test was performed and revealed low risk. One fetus appeared to be female and the other male at the 14th gestational week. Second trimester anatomic scanning results were otherwise normal for both fetuses. The newborns delivered at term appeared to be normal female and male babies phenotypically. At the fourth month, buccal cell analysis showed chimeric karyotypes, 46,XX[98]/46,XY[2] and 46,XY[98]/46,XX[2] in the female and male infant, respectively. The recognition of sex discordance despite monochorionicity may be a clue for the diagnosis of such rare cases of chimerism in dizygotic twins, most of which occur in pregnancies obtained by assisted reproductive technology.