Risks of perinatal mortality and morbidity (stillbirth, neonatal death, or 5-min Apgar score <4) by birthweight (excluding deaths due to congenital anomalies).

aThe occurrence of stillbirth or neonatal death.
bData are adjusted ORs estimated from multiple regression models adjusted for maternal age, gestational age, parity, infant sex, maternal diabetes, chronic hypertension, pregnancy associated hypertension, eclampsia, smoking, social economic status (marital status, education) and month of prenatal care started.
cThe occurrence of stillbirth, neonatal death, or 5-min Apgar score less than four.

a. 死胎或新生儿死亡的发生情况。
b. 本数据为经多元回归模型估算得到的校正比值比（adjusted odds ratio），该模型已针对以下因素进行校正：产妇年龄、胎龄、产次、婴儿性别、产妇糖尿病、慢性高血压、妊娠相关性高血压、子痫、吸烟状况、社会经济状况（婚姻状况、受教育程度）以及首次产前检查开始的月份。
c. 死胎、新生儿死亡，或5分钟阿普加（Apgar）评分低于4分的发生情况。