Clinical Research Directory

Inclusion Criteria: * 1\. Pregnant women plan to delivery and participate in child care in our hospital; 2. Pregnant women plan to reside in Shenzhen for at least 7 years; 3. Pregnant women who show interest in the study and agree to provide informed consent; 4. Gestational weeks are less than 20 weeks.Those who will agree that their neonatal will be included in the study and be followed up regularly in our child health clinic until an age of 7 years. Exclusion Criteria: * Pregnant women who have been pregnant for more than 20 weeks; refuse to participate; unable to guarantee delivery in our hospital or can't participate in child care in our hospital; mentally incapacitated and need guardians; or be unwilling to sign informed consent.