Prediction of intrauterine death and severe preterm delivery in twin pregnancies discordant for major fetal abnormality

Abstract

ObjectiveTo investigate predictors of spontaneous fetal death and preterm delivery in twin pregnancies with one fetus affected by a major structural malformation. Study designRetrospective study (1999–2012) conducted at a tertiary teaching hospital involving 51 twin pregnancies (dichorionic=31, monochorionic diamniotic=15, monochorionic monoamniotic=4, not established=1) with a major fetal abnormality, enrolled before 26 weeks and managed expectantly. Primary outcomes: spontaneous fetal death, and/or delivery before 32 weeks. Prediction was examined with stepwise logistic regression analysis, and independent variables included: maternal age, gestational age at diagnosis, chorionicity, fetal gender, number and type of fetal abnormalities. Significance level was set at 0.15. ResultsFetal abnormalities were diagnosed at a mean gestation of 21.5±3.7 weeks: cardiac abnormalities were observed in 31.4% of abnormal fetuses, abdominal wall defects in 29.4%, central nervous system 21.5%, spine 17.6%, effusions 17.6%, noncardiac thoracic abnormalities 15.7%, genital and urinary system 13.7%, limbs and soft tissue 3.9%, intestinal 1.9% and facial defects 1.9%. Fetal death occurred in 15 (29.4%) abnormal fetuses and was significantly correlated with the number of fetal malformations (p=0.02, OR=2.54, 95% CI=1.14–5.62), presence of effusion/hydrops (p=0.06, OR=4.7, 95% CI=0.95–24) and monochorionic placenta (p=0.11, OR=2.8, 95% CI=0.78–9.8). Normal co-twin fetal death occurred in four cases (7.8%) and was related to monochorionic pregnancies (p=0.14, OR=5.8, 95% CI=0.56–61). Delivery before 32 weeks was observed in 14 (27.5%) pregnancies and was related to presence of effusion/hydrops (p=0.04, OR=5.5, 95% CI=1.07–28). ConclusionSpontaneous fetal death and/or delivery before 32 weeks in twin pregnancies with one fetus affected by a major structural malformation are related to the number of abnormalities diagnosed and presence of fetal effusion or hydrops.