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Published on: November 20, 2015
[Factors influencing the occurrence of small for gestational age at different degrees]
Yi-Min Zhang1, Shu-Ming Shao1, Chen Yu
1Department of Pediatrics, Peking University People's Hospital, Beijing 100044, China (Zhang X-R, Email: icy.zhang@163.com); School of Public Health, Peking University, Beijing 100191, China.
Objectives:
To investigate the factors influencing the occurrence of small for gestational age (SGA) at different degrees and provide a basis for early identification of severe SGA cases.
Methods:
Neonatal and maternal prenatal information were retrospectively collected from January 2018 to December 2022 at Peking University People's Hospital. The neonates were divided into three groups: severe SGA group (birth weight below the 3rd percentile for gestational age and sex), mild SGA group (birth weight ≥3rd percentile and <10th percentile), and non-SGA group (birth weight ≥10th percentile). An ordered multinomial logistic regression model was used to analyze the factors influencing the occurrence of SGA at different degrees.
Results:
A total of 14 821 neonates were included, including 258 cases (1.74%) in the severe SGA group, 902 cases (6.09%) in the mild SGA group, and 13 661 cases (92.17%) in the non-SGA group. The proportions of preterm births and stillbirths were higher in the severe SGA group compared to the mild SGA and non-SGA groups (P<0.0125). The proportion of neonatal asphyxia was higher in both the severe SGA and mild SGA groups compared to the non-SGA group (P<0.0125). Ordered multinomial logistic regression analysis showed that maternal pre-pregnancy underweight (OR=1.838), maternal pre-pregnancy obesity (OR=3.024), in vitro fertilization-embryo transfer (OR=2.649), preeclampsia (OR=1.743), connective tissue disease during pregnancy (OR=1.795), nuchal cord (OR=1.213), oligohydramnios (OR=1.848), and intrauterine growth restriction (OR=27.691) were all associated with a higher risk of severe SGA (P<0.05). Maternal parity as a multipara (OR=0.457) was associated with a lower likelihood of severe SGA (P<0.05).
Conclusions:
Maternal pre-pregnancy underweight, maternal pre-pregnancy obesity, in vitro fertilization-embryo transfer, preeclampsia, connective tissue disease during pregnancy, oligohydramnios, nuchal cord, and intrauterine growth restriction are closely related to the occurrence of more severe SGA. Maternal parity as a multipara acts as a protective factor against the occurrence of severe SGA.
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