Table 1.

Participant eligibility and exclusion criteria

Eligibility criteria
(1)	Pregnant women whose babies are due between August 1, 2011 and the end of the registration period.
(2)	Pregnant women who live in the areas designated by the regional center and who are expected to live within Japan in the future.
(3)	Pregnant women who visit the cooperating medical facilities or claimed their maternity handbook at the local municipal offices.
Exclusion criteria
(1)	Pregnant women and fathers of children who do not consent to participate in this study.
(2)	Pregnant women or fathers who have difficulties filling in the questionnaire forms.
(3)	Pregnant women who are expected to give birth outside the target area and are thus unable to provide an umbilical cord blood samples.