Characteristics and Birth Outcomes of Pregnant Women Treated with Corticosteroid after Fetal Reduction

Background and Purpose: Compared with singleton births, twin pregnancies are at increased risk of significant child morbidity, particularly cerebral palsy, after high-order fetal reduction. This is termed the vanishing-twin syndrome, and is an important etiology of cerebral palsy. Antenatal corticosteroid therapy (CCT) is widely used during preterm labor to enhance lung maturity. The use of dexamethasone, however, increases the risk for detrimental long-term neurodevelopmental effects. Thus, in this study we assess the effect of CCT on neurological disability and congenital abnormality in twins over 2 years of age after fetal reduction. Methods: The CCT (38 sets of twins) and control (56 sets) groups were compared for the incidences of cerebral palsy and congenital abnormalities, as well as mean birth weight, maternal age, and mean gestational age at delivery and at fetal reduction using records from Shin-Kong Memorial Hospital for the period 1992~2000. Results: There were 94 quadruplet-reduced sets of twins in our study. All of these twins were alive and aged over 2 years at the time of this writing. The gestational age at the time of delivery was 32.4±2.7 weeks for the CCT group vs. 36±2.9 weeks for the controls, with mean birth weights of 2099±555 vs. 2405±519g, respectively (p＜0.01). All 94 sets of twins were delivered by cesarean section, with only 1 case of cerebral palsy in the CCT group, while the others had developed normally by the age of 2 years. Only mean birth weight and gestational age at delivery showed significant differences in comparisons of the 2 groups of twins. Conclusion: Limiting the number of embryo transfers is essential for preventing adverse effects of the vanishing-twin syndrome. When reduction has been performed, a prolonged gestational age at delivery is mandatory for twin babies.