The impact of chorionicity on pregnancy outcome and neurodevelopment at 2 years old among twins born preterm: the EPIPAGE‐2 cohort study

Abstract

Objective To compare the short-and mid-term outcomes of preterm twins by chorionicity of pregnancy. Design Prospective nationwide population-based EPIPAGE-2 cohort study. Setting 546 maternity units in France, between March and December 2011. Population A total of 1700 twin neonates born between 24 and 34 weeks of gestation. Methods The association of chorionicity with outcomes was analysed using multivariate regression models. Main outcome measures First, survival at 2-year corrected age with or without neurosensory impairment, and second, perinatal, short-, and mid-term outcomes (survival at discharge, survival at discharge without severe morbidity) were described and compared by chorionicity. Results In the EPIPAGE 2 cohort, 1700 preterm births were included (850 twin pregnancies). In all, 1220 (71.8%) were from dichorionic (DC) pregnancies and 480 from monochorionic (MC) pregnancies. MC pregnancies had three times more medical terminations than DC pregnancies (1.67 versus 0.51%, P < 0.001), whereas there were three times more stillbirths in MC than in DC pregnancies (10.09 versus 3.78%, P < 0.001). Both twins were alive at birth in 86.6% of DC pregnancies compared with 80.0% among MC pregnancies (P = 0.008). No significant difference according to chorionicity was found regarding neonatal deaths and morbidities. Likewise, for children born earlier than 32 weeks, the 2-year follow-up neurodevelopmental results were not significantly different between DC and MC twins. Conclusions This study confirms that MC pregnancies have a higher risk of adverse outcomes. However, the outcomes among preterm twins admitted to neonatal intensive care units are similar irrespective of chorionicity.

Effect of gestational age at laser therapy on perinatal outcome in monochorionic diamniotic pregnancies affected by twin‐to‐twin transfusion syndrome

“…Premature neonates born from monochorionic pregnancies, even after TTTS, have similar long-term neurodevelopmental outcome, when compared with other twin pregnancies. 33 Second, we found no relationship between postoperative TAPS, TTTS recurrence and gestational age at laser therapy, which are major contributors to the occurrence of neurological lesions. 3 Our results support the idea of a direct correlation between gestational age at fetal therapy and perinatal outcome, as the association between survival outcomes and the gestational age at surgery remained significant after adjustment on potential severity factors.…”

The spectrum of brain malformations and disruptions in twins

“…The near equal proportion of MZ and DZ twins with structural defects found in our cohort has not been reported previously but fits well with a recent comprehensive analysis of 1,493 twin placentas from British Columbia (Jahanfar & Lim, 2018 (Tosello et al, 2020). The same British Columbia study of twin placentas found a significantly higher risk of unequal placental sharing and abnormal anastomoses in males compared to females for both same sex twin pairs (enriched for MZ)…”

“…An excess of male twins was also observed with amyoplasia (Hall et al, 2014). Some studies of neurodevelopmental outcomes in twins include sex as a variable feature but do not report any differences, implying that any differences were not significant (Dostanic, Sustersic, & Paro-Panjan, 2018;Tosello et al, 2020). However, we predict that studies including larger numbers of twins with individual level data will support an increased risk in males based on analysis of twin placentas, discussed below (Jahanfar & Lim, 2018).…”

“…While HYDN and POR have been described in twins, we found less specific cerebral volume loss especially involving white matter in 5 of 10 subjects in this group. (Glinianaia et al, 2008;Hall, 1996;Hall, 2003;Kosinska-Kaczynska et al, 2016;Scheller & Nelson, 1992;Tosello et al, 2020). We looked for and found a significant excess of MZ twins compared to a population cohort (Tables 5 and 6), although the difference was not significant if we used the predicted zygosity ratio from Weinberg's differential rule or reclassified all UZ twins as DZ.…”

Selective intrauterine growth restriction of monochorionic diamniotic twin pregnancies: What is the neonatal prognosis?

“…Finally, the assimilation that our study suggests between sIUGR and IUGR is strictly limited to morbidity-mortality information in surviving newborns. In a recent study, the perinatal and two-year outcomes of twins born before 32 weeks were not significantly different between the monochorionic and bichorionic twin groups [35]. In other cohort studies, with inclusion to term, the number of sIUGRs was higher in monochorionic twins [36,37].…”