Outcomes
Because the NFPHEP collected data of pregnancy outcomes from medical records, all the pregnancy outcomes documented were over gestational age of 28 weeks and 0 days. The outcomes in present study were PTB (livebirth between 28 weeks and 0 days, and 36 weeks and 6 days of gestational age), large for gestational age (LGA, birth weight above the 90th percentile for gestational age by infants’ sex), small for gestational age (SGA, birth weight below the 10th percentile for gestational age by infants’ sex), primary caesarean delivery, shoulder dystocia or birth injury, and stillbirth (occurs between 28 or more completed pregnancy weeks).