Pregnancy outcomes in female childhood cancer survivors: Nationwide survey in Japan

Background The aim of this study was to investigate the outcomes of pregnancy in female childhood cancer survivors (CCS) in Japan, to encourage greater attention to the reproductive health of CCS. Methods This was a retrospective nationwide questionnaire survey of delivery at ≥22 weeks of gestation in CCS at perinatal centers registered with the Japanese Perinatologists Association between 2010 and 2014. We evaluated the maternal characteristics, pregnancy and neonatal outcomes and the relationship between cancer treatment and these outcomes. Results The total number of CCS was 61, and the total number of deliveries was 71, corresponding to 0.019% of total deliveries. Regarding cancer, 46% of the patients had had leukemia. Epilepsy was seen in seven (11%). Mean gestational age at delivery was 37.9 weeks. The rate of preterm delivery was 24%. Mean birthweight was 2,718 g. There were three congenital anomalies (4.2%). The rate of preterm delivery was higher and mean birthweight lower in the women treated with radiotherapy than in those without radiotherapy (42% vs 16%, P = 0.025; 2,436 ± 737 g vs 2,827 ± 483 g, P = 0.010). The adjusted OR of radiotherapy for preterm deliveries was 3.53 (P = 0.049). Conclusions Although the number of deliveries by CCS was low in Japan, the pregnancy outcomes were favorable. The important points for managing pregnancy in CCS were preterm delivery as an obstetric complication, especially in CCS who had been treated with radiotherapy, and epilepsy as a maternal complication, which may be related to previously received treatment.