Birth defect rate in Fukushima at same level as national average: health survey

13 February 2015

The average rate of birth defects and other abnormalities among newborns in Fukushima Prefecture in fiscal 2011-2013, the first three years since the March 2011 nuclear disaster at the Fukushima Daiichi atomic power plant of Tokyo Electric Power Co., was about the same as the national average in Japan, according to a survey conducted by the prefectural government on the impact of the accident on its residents’ health.

The rate in Fukushima was in the 2% range compared with the commonly accepted average of 3%-5%. The finding was reported during a meeting of a study committee held in Fukushima city on Feb. 12 to discuss the results of the survey. Committee members said the finding shows it is unlikely that expectant and nursing mothers are being affected by radiation in the prefecture.

The survey tracked the number of newborns who showed congenital anomalies of the heart or the spine, Down syndrome and other defects between the 12th week of pregnancy to one month after birth. The rate of occurrence in fiscal 2011 was 2.85% among 8,538 respondents, 2.39% among 6,993 respondents in fiscal 2012 and 2.35% among 7,067 respondents in fiscal 2013. The survey also found that the rates did not differ significantly among different regions in the prefecture.

The natural rate of occurrence of such birth defects is believed to be around 3% to 5% according to guidelines for obstetrical practice in Japan drawn up by the Japan Society of Obstetrics and Gynecology and other experts. Meanwhile, figures compiled by the Japan Association of Obstetricians and Gynecologists put the national average in 2012 at 2.34%. The rates of premature births and low-birth weight infants in the northeastern Japan prefecture during the three-year period from April 2011 also showed no major difference from nationwide trends, according to the survey.

“The rates of occurrence (in Fukushima) do not differ from the commonly accepted figures so it is unlikely that there was any impact from radiation,” said Keiya Fujimori, professor at Fukushima Medical University’s department of obstetrics and gynecology. “However, it is necessary to continue conducting the survey and analyze findings.”

In light of the results that show the unlikelihood of any radiation effects on expectant and nursing mothers, Kenichi Hata, head of the Fukushima Prefecture Association of Obstetricians and Gynecologists and director of Meiji Hospital in Fukushima city, said: “It is important to publicize the survey findings nationwide.”