Pregnancy outcomes in children, adolescents, and young adults that survived cancer: A nationwide survey in Japan.

AIM Recent advances in cancer treatment have improved the prognosis of child, adolescent, and young adult (CAYA) cancer survivors. This study aimed to examine the current status of pregnancy outcomes among female cancer survivors in Japan. METHODS The first questionnaire was sent to 633 major tertiary institutions certified by the Japan Society of Obstetrics and Gynecology to identify institutions managing cases of pregnant cancer survivors between January 2011 and December 2015. The second questionnaire was sent only to institutions with pregnant cancer survivors during the study period. RESULTS We analyzed 2242 singleton deliveries of cancer survivors based on the responses received in the second questionnaire (199/255 responses; 78.0%). The three most frequent types of malignant tumors were uterine cervical (23.4%), breast (17.6%), and thyroid cancers (17.5%). Conception was aided by the use of assisted reproductive technology in 17.0% of the patients. The proportions of mothers aged 35-39.9 and ≥ 40 years were 36.5% and 11.8%, respectively. The prevalence of preterm birth (PTB) at <37, <34, and < 32 weeks' gestation were 16.7%, 6.8%, and 4.3%, respectively. The proportion of infants with low birth weight (LBW) was 18.9%. CONCLUSION The present study findings suggest that advanced maternal age was common among pregnant cancer survivors and these survivors often gave birth to PTB and LBW infants in Japan. The likelihood of adverse pregnancy outcomes should be considered by healthcare providers when planning counseling and perinatal care for cancer survivors.