Using appropriate pre-pregnancy body mass index cut points for obesity in the Chinese population: a retrospective cohort study

Table 1 Baseline characteristics of this study’s population^a

	Prepregnancy BMI category (kg/m²)
	BMI<19 (n= 3135)	19≤BMI<22 (n= 5113)	22≤BMI<25 (n= 2422)	25≤BMI<28 (n= 626)	BMI≥28 (n= 198)	P
Maternal age (years)	29.7 ± 4.0	31.4 ± 4.2	32.5 ± 4.3	33.0 ± 4.2	32.5 ± 4.4	<0.001
Nulliparity	2482 (79.2)	4093 (80.1)	1943 (80.2)	504 (80.5)	156 (78.8)	0.82
Previous C/S	276 (8.8)	711 (13.9)	448 (18.5)	147 (23.5)	41 (20.7)	<0.001
Gestational week	38.9 ± 1.56	38.9 ± 1.5	38.7 ± 1.6	38.6 ± 1.7	38.4 ± 1.9	<0.001
Birth weight (grams)	3060.7 ± 425.6	3159.9 ± 437.2	3210.6 ± 477.7	3263.4 ± 486.1	3272.5 ± 545.3	<0.001

BMI body mass index; C/S caesarean section.
^aContinuous variables were presented as mean ± SD; qualitative variables were presented as N (%)

ISSN: 1477-7827