Comparison of maternal, fetal, obstetric and neonatal outcomes for 234 triplet pregnancies conceived in vivo versus IVF and ICSI conceptions.

RESEARCH QUESTION: Is there a difference in maternal, fetal, obstetric and neonatal outcomes for triplet pregnancies when comparing in vivo conceptions with those conceived by assisted reproductive technology (ART)?

DESIGN: This single-centre, retrospective cohort study included all triplet pregnancies followed up at La Paz University Hospital, Madrid between 2000 and 2022. The characteristics of the pregnant women, and maternal, fetal, obstetric and perinatal outcomes were examined. Univariate and multivariate statistical analyses were performed.

RESULTS: In total, 234 triplet pregnancies were analysed: 92 in the natural and assisted insemination conception group (in-vivo conception) and 142 in the in vitro fertilization and intracytoplasmic sperm injection conception group (ART conception). ART triplet pregnancies were more common between 2000 and 2010 (P = 0.003). The percentage of monochorionic triamniotic pregnancies was significantly higher (P = 0.02) in the in-vivo conception group, and the percentage of dichorionic triamniotic pregnancies was significantly higher (P = 0.003) in the ART conception group. After adjusting for confounders, intrauterine growth restriction (IUGR) remained significantly more common in the ART conception group (adjusted odds ratio 8.65, 95% CI 1.66-45.03; P = 0.01). Differences in maternal age (P = 0.61), threatened preterm labour (P = 0.10), Apgar score ≤5 at 5 min (P = 0.99), umbilical cord pH <7.20 (P = 0.99) and fetal death (P = 0.99) disappeared after adjustment for confounders.

CONCLUSION: ART triplet pregnancies had a higher rate of IUGR than in vivo triplet pregnancies. This could be related to higher maternal age, and higher rates of Apgar score ≤5 at 5 min and umbilical cord pH <7.20 in these pregnancies. In these cases, placental examination could provide valuable information.