The DEEP cohort is the first population-based cohort of pregnant population in China that longitudinally documents drug uses throughout the pregnancy life course and adverse pregnancy outcomes.

The DEEP cohort is the first population-based cohort of pregnant population in China that longitudinally documents drug uses throughout the pregnancy life course and adverse pregnancy outcomes. The main goal of the study aims to monitor and evaluate the safety of drug use through the pregnancy life course in the Chinese setting. The DEEP cohort is developed primarily based on the population-based data platforms in Xiamen, a municipal city of 5 million population in southeast China. Based on these data platforms, a pregnancy-centered registry was developed that documented health care services and outcomes in the maternal and other departments. For identifying drug uses, a drug prescription database was specifically developed by using electronic healthcare records documented in the platforms across the primary, secondary and tertiary hospitals. By linking the pregnancy registry and prescription database through a unique identifier, the DEEP cohort was developed. All the pregnant women and their offspring in Xiamen are provided with health care and followed up according to standard protocols in the region, including antenatal care, delivery care, postpartum follow-up and childhood follow-ups. The primary adverse outcomes - congenital malformations - are collected using a standardized Case Report Form.

Inclusion Criteria:

• Pregnant women who registered at the Maternal and Child Health Management Platform in Xiamen.

Exclusion Criteria:

• None

All pregnant women registered at the Maternal and Child Health Management Platform were enrolled.

From January 2013, all pregnant women who registered at the Maternal and Child Health Management in Xiamen was included in this cohort.

Following the policy of Xiamen Health Commission, research institutions could apply for data access by submitting a formal study protocol, subjected to approval by the Xiamen Health and Medical Big Data Center and the Chinese Evidence-based Medicine Center. Ethical review and research registration are mandatory for all studies.