How have the triplet pregnancies baseline characteristic and its outcomes changed over the last two decades?

Abstract

Triplet pregnancies are high-risk pregnancies, and baseline characteristics and gestational care protocols have changed over years. The objective of this study is to compare the baseline characteristics and the prevalence of maternal, fetal, obstetric, and perinatal outcomes in triplet pregnancies between 2013 and 2024 (PII) and 2000 and 2012 (PI). This is a single-center, observational retrospective case-control study that includes all triplet pregnancies followed up at the La Paz University Hospital between 2000 and 2024. Univariate and multivariate statistical studies were performed. 234 triplet pregnancies were analyzed: 140 (PI group) and 94 (PII group). Maternal age (P = 0.04) and nulliparous women (P < 0.01) were higher in PII group, although ART pregnancies were more frequent in PI (P = 0.04). The dichorionic triamniotic pregnancies percentage was significantly higher (P < 0.01) in PII group and the trichorionic triamniotic percentage was significantly higher (P < 0.01) in PI group. Preeclampsia (P < 0.01), intrauterine growth restriction (P < 0.01), fetal death (P < 0.01), neonatal death (P = 0.04), and small for gestational age (P < 0.01) were significantly more frequent in PII group. Threatened preterm labour (P < 0.01) and extreme premature births (P < 0.01) were significantly more frequent in the PI group. After adjusting for confounders, premature birth was the only one that remained significant (P = 0.01). The baseline characteristics of the PII group (higher maternal age, more nulliparous women, and higher rate of dichorionic triamniotic) might be associated with a higher rate of obstetric and fetal complications during this period. Premature births and threatened preterm labour have decreased over the years, probably related to the advances in gestational care.