Clinical features and short-term outcomes of triplet pregnancies in Japan

Objective: To review clinical features and short-term outcomes of triplet pregnancies among Japanese women. Methods: A retrospective analysis was carried out among 320 Japanese women with triplet pregnancies (8 monochorionic, 75 dichorionic, and 150 trichorionic triplets; 87 with unknown placental chorionicity) who delivered at 22 gestational weeks or more between January 2005 and December 2008. Results: Delivery was by cesarean for 315 (98%) women. Gestational age at delivery was 32.3 ± 2.8 weeks (mean ± SD) and 33.2 weeks (median), and 97%, 61%, and 14% of women delivered at less than 37, less than 34, and less than 30 gestational weeks, respectively. For live-born infants, mean birth weight was 1762 ± 437 g, 1608 ± 396 g, and 1406 ± 380 g for the heaviest, middle, and lightest triplet, respectively. Eighteen (5.6%) women experienced perinatal mortality (3 triplets for 1 woman, 2 triplets for 4 women, and 1 triplet for 13 women). Perinatal mortality was 25 deaths per 1000 deliveries, and decreased with increasing number of chorionic membranes (125, 44, and 20 per 1000 mono-, di-, and trichorionic triplet deliveries, respectively). Conclusion: Short-term outcomes were good among triplet pregnancies in Japan. The data may be useful for counseling Japanese women with triplet pregnancies.