Eight-year trends in the effect of the Great East Japan Earthquake on obstetrics outcomes using the Fukushima Health Management Survey

Information on longitudinal effects of natural/environmental disasters on obstetrics outcomes is limited. This study analyzed longitudinal changes, over an 8-year period, in obstetrics outcomes after the Great East Japan Earthquake and the Fukushima power plant accident. We used data from the first 8 years of the Pregnancy and Birth Survey by the Fukushima prefectural government and compared data on obstetrics outcomes by year. Longitudinal changes in the occurrence of preterm birth before 37 gestational weeks, low birth weight, and anomalies in newborns were assessed in all six districts in Fukushima. The total number of participants was 57537. In 8 years, maternal age, rate of conception after sterility treatment, and incidence of cesarean section delivery tended to increase (p<0.001, p<0.001, and p=0.009, respectively). Although significant differences were observed in preterm birth and low birth weight among the districts (p=0.020 and p=0.025, respectively), no significant trend was observed in the preterm birth, low birth weight, and anomalies in newborns in all six districts (p=0.096, p=0.269, and p=0.239, respectively). The Great East Japan Earthquake and the Fukushima power plant accident were associated with increased incidence of cesarean section delivery but had no significant adverse effects on obstetrics outcomes.