NORA study
The Neonatal and Obstetric Risk Assessment (NORA) study is a
longitudinal prospective study conducted in KK Women’s and Children’s
Hospital, Singapore, between September 1, 2010, and August 31, 2014.
Participants are women with singleton pregnancies who attended antenatal
clinics from 1st trimester. Women with viable
singleton pregnancies confirmed by ultrasonography at less than 14 weeks
of amenorrhea were considered eligible. Patients with chronic medical
conditions known to be associated with adverse pregnancy outcomes (such
as systemic lupus erythematosus) and pregnancies complicated by
aneuploidy or foetal anomalies were excluded. These women were followed
up throughout the antenatal course. Women with unsuccessful pregnancies
(termination, miscarriage were also excluded. Gestational age was
calculated from the estimated due date which was confirmed from the
ultrasound scan in the 1st trimester based on crown
rump length. A written informed consent was obtained from all
participants. NORA study was approved by the SingHealth Centralised
Institutional Review Board Ethics Committee, Singapore (CIRB Ref No.
2010/214/D). In the present analysis, 10 women who had pre-existing
hypertension were excluded, making the final number of subjects 916.