The Huizhou mother-infant cohort was set up to investigate the effect of dietary factors and environmental exposures during pregnancy on health consequences of mothers and offsprings in Huizhou, China.

Huizhou mother-infant cohort (No-worry Baby Project) is a scientific research/public health project jointly initiated by Huizhou First Maternity and Child Healthcare Hospital and School of Public Health, Sun Yat-sen University. The project plans to recruit 10,000 participants since early pregnancy and follow up for three years after birth in the first stage. Biological samples, data from questionnaires survey and clinical information will be collected for both mothers and infants. The study is aimed to investigate the effects of dietary factors and environmental exposures during pregnancy on infants' health as well as the prognosis of diseased mothers. The study will have essentially both clinical and public health implications to find effective strategies for prevention and management of a range of chronic disorders (above mentioned) during pregnancy and exploration of the possible impacts on offspring health. The cohort will provide scientific basic for improvement of mother and infant's health.

Inclusion Criteria:

• Pregnant women who have plan to delivery and participate in child care in Huizhou hospital;
• Pregnant women who have resided in Huizhou for at least 3 years;
• Pregnant women who are consent for specimens and data collection and follow-ups for both mother and infant.

Exclusion Criteria:

• Pregnant women who are with gestational age more than 24 weeks ;
• Pregnant women who refuse to participate or be unwilling to sign informed consent;
• Pregnant women who are mentally incapacitated and need guardians.

Eligible pregnant women will be recruited from Huizhou First Maternal and Child Care Service Center.