Maternal gestational weight gain and adverse pregnancy outcomes in non-diabetic women

Figures & data

Figure 1. Flowchart for study population inclusion. OGTT: oral glucose tolerance test; GWG: gestational weight gain.

Inadequate GWG group: Weight gain during pregnancy is below the recommended range.

Adequate GWG group: Weight gain during pregnancy is in the recommended range.

Excessive GWG group: Weight gain during pregnancy is above the recommended range.

Table 1. Baseline characteristics and pregnancy outcomes in pregnant women with different GWG.

Overall	Toal population	Total pregnancy weight change			P
	All	Inadequate	Adequate	Excessive
N	30910	7569	13088	10253
Age, years	31.09 ± 4.27	31.68 ± 4.27	31.08 ± 4.20	30.67 ± 4.31	<0.001
Gestational age, week	38.75 ± 1.50	38.36 ± 1.85	38.79 ± 1.39	38.98 ± 1.28	<0.001
Pp-BMI, kg/m^2	20.79 ± 2.73	20.66 ± 2.57	20.46 ± 2.64	21.32 ± 2.86	<0.001
Pp-BMI category, n (%)
<18.5	5919 (19.15)	1664 (21.98)	3138 (23.98)	1117 (10.89)	<0.001
18.5–24.9	22718 (73.50)	5643 (74.55)	9210 (70.37)	7865 (76.71)
≥25	2273 (7.35)	262 (3.46)	740 (5.65)	1271 (12.40)
Parity, n (%)					<0.001
0	18279 (59.14)	4219(55.74)	7673 (58.60)	6387 (62.29)
1	12043 (38.96)	3205 (42.34)	5175 (39.54)	3663 (35.73)
≥2	588 (1.90)	145 (1.92)	240 (1.83)	203 (1.98)
Gravidity, n (%)					<0.001
1	12281 (39.73)	2837 (37.48)	5247 (40.09)	4197 (40.93)
2	9409 (30.44)	2495 (32.96)	3972 (30.35)	2942 (28.69)
≥3	9220 (29.83)	2237 (29.55)	3869 (29.56)	3114 (30.37)
Total GWG, kg	14.28 ± 4.16	9.37 ± 2.07	13.75 ± 1.75	18.58 ± 2.93	<0.001
Birth weight, g	3302.83 ± 453.66	3128.41 ± 476.40	3293.70 ± 417.37	3443.23 ± 433.95	<0.001
HbA1c (%)	5.00 ± 0.31	5.00 ± 0.32	4.99 ± 0.30	5.02 ± 0.31	<0.001
Fasting glucose (mmol/l)	4.41 ± 0.39	4.41 ± 0.43	4.39 ± 0.38	4.43 ± 0.38	<0.001
1-h glucose (mmol/l)	8.05 ± 1.70	8.39 ± 1.85	8.00 ± 1.66	7.87 ± 1.60	<0.001
2-h glucose (mmol/l)	7.01 ± 1.45	7.38 ± 1.68	6.96 ± 1.41	6.81 ± 1.26	<0.001
GDM, n (%)	6170 (19.96)	2312 (30.55)	2406 (18.38)	1452 (14.16)	<0.001
Family history of diabetes, n (%)	283 (0.91)	112 (1.48)	109 (0.83)	62 (0.60)	<0.001
Pregnancy outcomes
Macrosomia (≥4000 g), n (%)	1707 (5.52)	154 (2.03)	551 (4.21)	1002 (9.77)	<0.001
SGA (<10 quartile), n (%)	1747 (5.65)	693 (9.16)	689 (5.26)	365 (3.56)	<0.001
LGA (>90 quartile), n (%)	2748 (8.89)	303 (4.00)	961 (7.34)	1484 (14.47)	<0.001
Preterm birth (<37 week), n (%)	1675 (5.42)	734 (9.70)	630 (4.81)	311 (3.03)	<0.001

A continuous variable is expressed as a mean ± SD, and a categorical variable is defined as n (%).

GWG: gestational weight gain; BMI: body mass index; GDM: gestational diabetes mellitus; SGA: small for gestational age; LGA, large for gestational age.

P values were calculated using one-way ANOVA with Dunn’s test (for continuous variables) or Chi-square test (for categorical variables), compared with the adequate GWG group.

Figure 2. The association between GWG and adverse pregnancy in women with and without GDM. A categorical variable is expressed as n (%). GWG: gestational weight gain; GDM: gestational diabetes mellitus; SGA: small for gestational age; LGA: large for gestational age. **P < 0.01, P values were calculated using Chi-square test, compared with GDM positive women.

Table 2. Relative risks of adverse pregnancy outcomes in no GDM women according to different GWG.

		Macrosomia		Preterm birth		LGA		SGA
	ALL	N(%)	a-OR	N(%)	a-OR	N(%)	a-OR	N(%)	a-OR
GDM-positive	6170	397 (6.43)	1	463 (7.50)	1	673 (10.91)	1	364 (5.90)	1
GDM-negative	24740	1310 (5.30)		1212 (4.90)		2075 (8.39)		1383 (5.59)
Inadequate	5257	101 (1.90)	0.54 (0.42-0.71)**	490 (9.30)	2.08 (1.73-2.51)**	193 (3.70)	0.62 (0.51-0.75)**	485 (9.20)	1.19 (0.98–1.44)
Adequate	10682	406 (3.80)	1.05 (0.87-1.27)	481 (4.50)	1.03 (0.85-1.24)	694 (6.50)	1.11 (0.95-1.29)	581 (5.40)	0.69 (0.57-0.83)**
Excessive	8801	803 (9.10)	2.19 (1.83-2.63)**	241 (2.70)	0.56 (0.46-0.69)**	1188 (13.50)	2.19 (1.89-2.54)**	317 (3.60)	0.50 (0.41-0.61)**

Adjusted for age, gestational age, preconception BMI, parity, gravidity, FPG, 1-h GLU, 2-h GLU, HbA1c, and family history of diabetes.

GWG: gestational weight gain; GDM: gestational diabetes mellitus; pp-BMI: pre-pregnancy body mass index; SGA: small for gestational age; LGA: large for gestational age; a-OR: adjusted odds ratio.

* P < 0.05, **P < 0.01, compared with GDM positive women.

Table 3. Subgroup analysis based on pp-BMI.

			Macrosomia		Preterm birth		LGA		SGA
		All	N(%)	a-OR	N(%)	a-OR	N(%)	a-OR	N(%)	a-OR
GDM-positive		6170	397 (6.43)	1	463 (7.50)	1	673 (10.91)	1	364 (5.90)	1
GDM-negative		24740	1310 (5.30)		1212 (4.90)		2075 (8.39)		1383 (5.59)
Inadequate		5257
BMI (kg/m^2)	<18.5	1303	13 (1.00)	0.29 (0.15-0.54)**	119 (9.13)	2.22 (1.70-2.90)**	20 (1.53)	0.25 (0.15-0.42)**	196 (15.04)	2.11 (1.66-2.67)**
	18.5-24.9	3839	86 (2.24)	0.57 (0.43-0.75)**	351 (9.14)	1.92 (1.58-2.34)**	167 (4.35)	0.66 (0.54-0.82)**	280 (7.29)	1.00 (0.81-1.23)
	≥25	115	2 (1.74)	0.43 (0.10-1.78)	20 (17.39)	3.52 (2.03-6.09)**	6 (5.21)	0.81 (0.35-1.87)	9 (7.83)	1.13 (0.53-2.39)
Adequate		10682
BMI (kg/m^2)	<18.5	2756	57 (2.06)	0.57 (0.42-0.78)*	94 (3.41)	0.82 (0.62-1.07)	97 (3.52)	0.59 (0.46-0.76)**	216 (7.84)	1.06 (0.8436-1.33)
	18.5-24.9	7496	316 (4.22)	1.03 (0.84-1.25)	353 (4.71)	1.02 (0.84-1.24)	552 (7.36)	1.13 (0.97-1.33)	348 (4.64)	0.66 (0.53-0.80)**
	≥25	430	33 (7.67)	1.79 (1.19-2.67)*	34 (7.91)	1.42 (0.96-2.11)	45 (10.46)	1.44 (1.03-2.02)*	17 (3.95)	0.59 (0.35-1.01)
Excessive		8801
BMI (kg/m^2)	<18.5	1023	81 (7.92)	2.01 (1.50-2.69)**	19 (1.86)	0.43 (0.25-0.72)*	107 (10.46)	1.91 (1.49-2.45)**	51 (4.99)	0.66 (0.46-0.93)*
	8.5-24.9	6868	609 (8.87)	2.10 (1.74-2.52)**	180 (2.62)	0.54 (0.43-0.68)**	919 (13.38)	2.14 (1.84-2.48)**	249 (3.63)	0.49 (0.40-0.61)**
	≥25	910	113 (12.42)	2.73 (2.10-3.55)**	42 (4.62)	0.77 (0.53-1.11)	162 (17.80)	2.62 (2.11-3.26)**	17 (1.87)	0.27 (0.16-0.46)**

Adjusted for age, gestational age, parity, gravidity, FPG, 1-h GLU, 2-h GLU, HbA1c, and family history of diabetes.

GWG, gestational weight gain; GDM: gestational diabetes mellitus; SGA: small for gestational age; LGA: large for gestational age; a-OR: adjusted odds ratio.

Underweight: BMI < 18.5 kg/m²; Normal weight: BMI 18.5–24.9 kg/m²; Overweight and obese: BMI ≥ 25 kg/m².

* P < 0.05, **P < 0.01, compared with GDM positive women.

Data availability statement

The datasets used and analysed during the current study are available from the corresponding author on reasonable request.