Exposure to radiation therapy is associated with female reproductive health among childhood cancer survivors: a meta-analysis study

Many epidemiological studies have revealed a positive correlation between medical radiation exposure and the reproductive health in female childhood cancer survivors. However, because of variations in the samples size, such studies showed partly inconsistent conclusions. The aim of this meta-analysis was to clarify the association between radiotherapy and the risk of reproductive health impairment for female who survived from childhood cancer. Fourteen cohort studies involving childhood radiotherapy were selected as the exposure of interest and the impaired reproductive health condition during the childbearing age as the outcome. Among meta-analysis of observational studies found in Pubmed and Embase from 1900 to 2014, we evaluated those relevant observational studies which surveyed the association of medical radiation and reproductive health in female childhood cancer survivors. Review Manager 5.2 and STATA 12.0 software were used to perform the meta-analysis. Study-specific estimations for each outcome were combined into a pooled relative risk (RR) with 95 % confidence interval (CI) by a meta-analytic approach. Based on a random-effects meta-analysis, significant association between infertility (RR = 1.28, 95 % CI = 1.16-1.42), acute ovarian failure (AOF) (RR = 9.51, 95 % CI = 5.03-17.96), low level of anti mullerian hormone (AMH) (< 1 ng/mL) (RR = 14.79, 95 % CI = 3.36-66.64), stillbirth (RR = 1.19, 95 % CI = 1.02-1.39) and low birth weight (RR = 2.22, 95 % CI = 1.55-3.17) were identified. Conversely, no significant results were found in abortion and congenital malformations. To the best of our knowledge, this is the first meta-analysis assessing the effect of medical radiation on female childhood cancer survivors' reproductive capability and pregnancy outcomes. Although there were some limitations, our meta-analysis further supported that radiotherapy was a risk factor for reproductive health problems of female who survived from childhood cancer.