The PREBIC investigates the effects of preconception exposures on offspring. Since 2018, the study has recruited over 17,000 adults trying to conceive who are participating in the national preconception care service programme in Chongqing Medical University in China. The study aims to recruit 40,000 participants (20,000 couples). Participants are followed up in three stages: preconception, pregnancy, and offspring. In the first stage (preconception), couples are followed up every three months following recruitment. This stage is terminated if pregnancy is achieved or if the couple fail to conceive within two  years. In the second stage (pregnancy), pregnant women are followed up three times throughout the three trimesters. Women who give birth have an extra follow-up at delivery. Follow-up in the third stage is of the offspring, occurring at 42 days, 6 months, 1 year, and 2 years after birth.

Recruitment is ongoing