Mother-Infant Cohort Study in Malaysia and China

Inclusion Criteria: * Pregnant women aged between 18 and 45 years old * Pregnant women who attend the antenatal check-up at the selected clinics/hospitals * Pregnant women with the gestational age of less than 12 weeks * Pregnant women who plan to attend post-natal check-ups for at least one year at the same clinic/hospital Exclusion Criteria: * Pregnant women who are diagnosed with immune deficiency * Pregnant women who have a multiple pregnancy and preterm delivery (\<37 weeks) * Pregnant women who plan to move out of the study area in the next one year * Pregnant women with fetal/newborn with congenital abnormalities