Study design and population
The prospective observational study was conducted between January 2018
and June 2021 in the department of Obstetrics from Guangzhou Women and
Children’s Medical Care Center, China. Singleton pregnancies from
20-36+6 gestational weeks were enrolled when maternal blood pressure
exceeded a pre-defined threshold (SBP≥140mmHg and/or DBP≥90mmHg), or
when primary chronic hypertension is present regardless of medication
intervention. Participants received oral and written information to
donate the surplus aliquots of serum samples during prenatal care for
scientific research before they gave written consent. The study was
approved by Institutional Ethics Committee of the Guangzhou Women and
Children’s Medical Center (Reference number: 2017022008).