Preconception exposure of mothers: The review of epidemiological research

A review of epidemiological research of the effects of preconception (prior to conception) radiation exposure to a mother’s body was presented. The anatomical and physiological characteristics that affect radiosensitivity and radioresistance of female reproductive system were reported. Biological prerequisites accounting for different effects of radiation exposure to animals and humans were indicated. The results that were published in open access on epidemiological assessments of the effects of preconception exposure of mothers to the health of their offspring were described based on various cohorts as examples. Analysis of the research work was performed for the cohort of the offspring of atomic bomb survivors in Japan, among the offspring of the individuals affected by radiation accidents and nuclear weapon tests, among the population of the sites with high natural level of radiation. The results of research work among the offspring of female patients exposed to diagnostic and therapeutical radiation and of the offspring of the mothers who were in contact with ionizing radiation sources at workplaces were presented. A special attention was paid to specifics of standardization of occupational exposure of female personnel according to national and international approaches. Generally, it was demonstrated that despite a wide range of epidemiological research works there is still no clear understanding of the effects of preconception exposure of mothers to their offspring. The total results of the analysis of the effects of maternal exposure in preconception period are quite controversial and usually involve a range of uncertainties. In the course of such sort of epidemiological research the following difficulties are indicated: poor verification of medical outcomes, primary data based on questionnaire surveys, lack of detailed information on individual exposure parameters, low statistical power of research works and too short period of follow up of the cohort under research. For this reason, the necessity of further analysis of the effects of exposure of female body was indicated involving detailed risk coefficients of unfavorable reproductive outcomes. Prospective trends for epidemiological analysis of preconception exposure of mothers were indicated. Feasibility of assessment of long-term preconception radiation exposure was described based on the cohort of female workers of Mayak Production Association that is the leading atomic enterprise in the national history.