Role of gestational weight gain in the association between breastfeeding duration and toddler neurodevelopment

doi:10.3969/j.issn.1674-8115.2026.02.007

Abstract

Abstract:

Objective ·To explore the role of gestational weight gain (GWG) in the association between breastfeeding duration and offspring neurodevelopment, and to identify appropriate GWG to sustain breastfeeding among reproductive-age women. Methods ·A prospective birth cohort study was conducted in Shanghai from 2010 to 2012. Mothers were recruited during mid- to late pregnancy and followed up until 24‒36 months postpartum, and information on GWG, breastfeeding duration, and related confounders was collected. Toddler neurodevelopment was assessed by the developmental quotient (DQ) of the Gesell Developmental Schedules (GDS) and scores from the Chinese Toddler Temperament Scale (CTTS). Two-piece-wise linear regression analyses were conducted (due to non-linear relationships) on the associations between breastfeeding duration and toddler neurodevelopment under different GWG stratifications, and between GWG and breastfeeding duration. Results ·A total of 225 mother-infant pairs were included in this study, and the mean breastfeeding duration was 7.4 months. After adjustment for related confounders, significant differences in the associations of breastfeeding duration with neurodevelopment were observed among mother-child pairs under different GWG stratifications. For pairs with excessive GWG, when breastfeeding duration was <6 months, longer duration was significantly associated with higher DQ in the language domains of GDS, and with lower scores in the approach-withdrawal and adaptability domains of CTTS, compared with the non-significant associations observed when the duration was ≥6 months (<6 months vs ≥6 months: P_{log-likelihood-ratio}-values<0.05). However, no significant differences (<6 months vs ≥6 months) were observed in the associations under appropriate/inadequate GWG. Significantly shorter breastfeeding duration was observed with increasing GWG when GWG was ≥17.5 kg. Conclusion ·GWG impacts the association between breastfeeding duration and toddler neurodevelopment. For offspring exposed to excessive maternal GWG during pregnancy, longer breastfeeding duration within 6 months or breastfeeding duration of ≥6 months is especially important for optimal neurodevelopment. GWG<17.5 kg is favorable for sustained breastfeeding.

Key words: gestational weight gain, breastfeeding, child, cognitive development, temperament

CLC Number:

R473.71

Xue Yue, Xu Jian, Jiang Yining, Yu Ting, Lin Yanfen, Zhang Yijing, Luo Zhongcheng. Role of gestational weight gain in the association between breastfeeding duration and toddler neurodevelopment[J]. Journal of Shanghai Jiao Tong University (Medical Science), 2026, 46(2): 188-199.

Figures/Tables 5

TrendMD

References 54

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Variable	Demographic characteristic	Breastfeeding duration/month	Unadjusted association with breastfeeding duration [β(95%CI)]
Per capita family income level/n(%)
<2 000 yuan/month	12 (5.3)	7.2±5.0	Reference
2 000‒4 999 yuan/month	64 (28.4)	7.2±5.2	0 (-2.9, 2.9)
5 000‒10 000 yuan/month	91 (40.4)	7.4±4.8	0.2 (-2.7, 3.0)
>10 000 yuan/month	58 (25.8)	7.7±4.0	0.5 (-2.4, 3.4)
Maternal factor
Maternal age at enrollment/n(%)
<25 years	19 (8.4)	5.1±3.5	Reference
≥25 years and <30 years	127 (56.4)	7.2±4.5	2.1 (-0.1, 4.4)
≥30 years	79 (35.1)	8.3±5.1	3.2 (0.9, 5.6)^①
Maternal educational degree/n(%)
Junior middle school or lower	15 (6.7)	8.5±4.7	Reference
Senior middle school	20 (8.9)	6.4±5.6	-2.1 (-5.2, 1.0)
University or college level	162 (72.0)	7.2±4.6	-1.4 (-3.8, 1.1)
Postgraduate level	28 (12.4)	8.7±4.1	0.1 (-2.8, 3.1)
Pre-pregnancy BMI/kg·m^-2	22.1±2.9	‒	0 (-0.2, 0.2)
Pre-pregnancy BMI group/n(%)
Underweight	17 (7.6)	7.4±3.0	Reference
Normal weight	157 (69.8)	7.6±4.8	0.9 (-1.5, 3.2)
Overweight	40 (17.8)	7.3±4.3	0.6 (-2.0, 3.3)
Obesity	11 (4.9)	5.7±6.9	-1.0 (-4.5, 2.6)
GSI during pregnancy/score	1.2±0.2	‒	-1.1 (-4.0, 1.8)
GSI at around 30 months postpartum/score	1.3±0.3	‒	-1.2 (-3.2, 0.9)
Gestational weeks/week	39.4±1.2	‒	0 (-0.5, 0.5)
Mode of delivery/n(%)
Vaginal	76 (33.8)	7.8±5.0	Reference
Caesarean section with indications	72 (32.0)	7.7±4.1	-0.1 (-1.6, 1.5)
Caesarean section without indications	77 (34.2)	6.7±4.9	-1.1 (-2.6, 0.4)
Parity/n(%)
Primiparous	214 (95.1)	7.3±4.6	Reference
Multiparous	11 (4.9)	8.3±7.0	1.0 (-2.0, 3.9)
GWG/kg	15.0±4.7	‒	-0.1 (-0.2, 0.1)
GWG group/n(%)
Appropriate/inadequate GWG	92 (42.8)	7.3±4.3	Reference
Excessive GWG	123 (57.2)	7.5±5.0	0.3 (-1.0, 1.6)
Maternal daily working hours after maternity leave/n(%)
>8 h	109 (48.7)	6.9±4.2	Reference
5‒8 h	90 (40.2)	7.2±4.5	0.3 (-1.0, 1.6)
<5 h	25 (11.2)	10.0±6.5	3.1 (1.1, 5.2)^②
Living with children per week/n(%)
7 d	166 (74.4)	8.0±4.8	Reference
≤6 d	57 (25.6)	5.6±3.9	-2.4 (-3.8, -1.0)^③
Offspring′s characteristic
Infant sex/n(%)
Boy	99 (44.0)	7.6±5.1	Reference
Girl	126 (56.0)	7.2±4.4	-0.4 (-1.6, 0.9)
Birth weight/kg	3.5±0.4	‒	0 (0, 0)

Variable	Demographic characteristic	Breastfeeding duration/month	Unadjusted association with breastfeeding duration [β(95%CI)]
Per capita family income level/n(%)
<2 000 yuan/month	12 (5.3)	7.2±5.0	Reference
2 000‒4 999 yuan/month	64 (28.4)	7.2±5.2	0 (-2.9, 2.9)
5 000‒10 000 yuan/month	91 (40.4)	7.4±4.8	0.2 (-2.7, 3.0)
>10 000 yuan/month	58 (25.8)	7.7±4.0	0.5 (-2.4, 3.4)
Maternal factor
Maternal age at enrollment/n(%)
<25 years	19 (8.4)	5.1±3.5	Reference
≥25 years and <30 years	127 (56.4)	7.2±4.5	2.1 (-0.1, 4.4)
≥30 years	79 (35.1)	8.3±5.1	3.2 (0.9, 5.6)^①
Maternal educational degree/n(%)
Junior middle school or lower	15 (6.7)	8.5±4.7	Reference
Senior middle school	20 (8.9)	6.4±5.6	-2.1 (-5.2, 1.0)
University or college level	162 (72.0)	7.2±4.6	-1.4 (-3.8, 1.1)
Postgraduate level	28 (12.4)	8.7±4.1	0.1 (-2.8, 3.1)
Pre-pregnancy BMI/kg·m^-2	22.1±2.9	‒	0 (-0.2, 0.2)
Pre-pregnancy BMI group/n(%)
Underweight	17 (7.6)	7.4±3.0	Reference
Normal weight	157 (69.8)	7.6±4.8	0.9 (-1.5, 3.2)
Overweight	40 (17.8)	7.3±4.3	0.6 (-2.0, 3.3)
Obesity	11 (4.9)	5.7±6.9	-1.0 (-4.5, 2.6)
GSI during pregnancy/score	1.2±0.2	‒	-1.1 (-4.0, 1.8)
GSI at around 30 months postpartum/score	1.3±0.3	‒	-1.2 (-3.2, 0.9)
Gestational weeks/week	39.4±1.2	‒	0 (-0.5, 0.5)
Mode of delivery/n(%)
Vaginal	76 (33.8)	7.8±5.0	Reference
Caesarean section with indications	72 (32.0)	7.7±4.1	-0.1 (-1.6, 1.5)
Caesarean section without indications	77 (34.2)	6.7±4.9	-1.1 (-2.6, 0.4)
Parity/n(%)
Primiparous	214 (95.1)	7.3±4.6	Reference
Multiparous	11 (4.9)	8.3±7.0	1.0 (-2.0, 3.9)
GWG/kg	15.0±4.7	‒	-0.1 (-0.2, 0.1)
GWG group/n(%)
Appropriate/inadequate GWG	92 (42.8)	7.3±4.3	Reference
Excessive GWG	123 (57.2)	7.5±5.0	0.3 (-1.0, 1.6)
Maternal daily working hours after maternity leave/n(%)
>8 h	109 (48.7)	6.9±4.2	Reference
5‒8 h	90 (40.2)	7.2±4.5	0.3 (-1.0, 1.6)
<5 h	25 (11.2)	10.0±6.5	3.1 (1.1, 5.2)^②
Living with children per week/n(%)
7 d	166 (74.4)	8.0±4.8	Reference
≤6 d	57 (25.6)	5.6±3.9	-2.4 (-3.8, -1.0)^③
Offspring′s characteristic
Infant sex/n(%)
Boy	99 (44.0)	7.6±5.1	Reference
Girl	126 (56.0)	7.2±4.4	-0.4 (-1.6, 0.9)
Birth weight/kg	3.5±0.4	‒	0 (0, 0)

Schedule	x±s	Single linear regression		Piece-wise linear regression				Likelihood ratio test
		Single linear regression		Breastfeeding<6 month		Breastfeeding≥6 month		Likelihood ratio test
		β (95%CI)	P value	β (95%CI)	P value	β (95%CI)	P value	P value
DQ of GDS
Gross motor	106.8±12.0	0 (-0.4, 0.4)	0.950	0.2 (-0.8, 1.1)	0.733	0 (-0.6, 0.5)	0.854	0.719
Fine motor	97.0±12.8	0 (-0.4, 0.5)	0.872	0.4 (-0.7, 1.4)	0.504	-0.1 (-0.7, 0.5)	0.748	0.492
Adaptive	113.4±9.9	0.1 (-0.2, 0.4)	0.668	0.4 (-0.3, 1.2)	0.273	-0.1 (-0.5, 0.4)	0.721	0.293
Language	112.8±14.8	0.3 (-0.2, 0.7)	0.304	1.0 (-0.1, 2.2)	0.082	-0.1 (-0.7, 0.6)	0.837	0.131
Interpersonal	104.4±12.5	0.2 (-0.1, 0.6)	0.210	1.0 (0.1, 2.0)	0.030	-0.1 (-0.6, 0.4)	0.779	0.059
Temperament scores of CTTS
Activity level	3.2±0.6	0 (0, 0)	0.941	0 (-0.1, 0)	0.186	0 (0, 0)	0.372	0.140
Biological rhythms	2.6±0.6	0 (0, 0)	0.799	0 (-0.1, 0)	0.126	0 (0, 0)	0.391	0.104
Approach-withdrawal	3.0±0.8	0 (-0.1, 0)	0.026	-0.1 (-0.1, 0)	0.015	0 (0, 0)	0.586	0.080
Adaptability	2.9±0.7	0 (-0.1, 0)	0.009	-0.1 (-0.1, 0)	0.002	0 (0, 0)	0.623	0.023
Intensity of reaction	3.9±0.6	0 (0, 0)	0.281	0 (-0.1, 0)	0.084	0 (0, 0)	0.885	0.141
Mood	2.6±0.6	0 (0, 0)	0.298	0 (-0.1, 0)	0.636	0 (0, 0)	0.462	0.955
Persistence	2.8±0.6	0 (0, 0)	0.355	0 (-0.1, 0)	0.267	0 (0, 0)	0.882	0.402
Attention	3.8±0.6	0 (0, 0)	0.478	0 (0, 0.1)	0.779	0 (0, 0)	0.594	0.992
Sensitivity	3.9±0.7	0 (0, 0)	0.854	0 (-0.1, 0.1)	0.833	0 (0, 0)	0.970	0.877

Schedule	x±s	Single linear regression		Piece-wise linear regression				Likelihood ratio test
		Single linear regression		Breastfeeding<6 month		Breastfeeding≥6 month		Likelihood ratio test
		β (95%CI)	P value	β (95%CI)	P value	β (95%CI)	P value	P value
DQ of GDS
Gross motor	106.8±12.0	0 (-0.4, 0.4)	0.950	0.2 (-0.8, 1.1)	0.733	0 (-0.6, 0.5)	0.854	0.719
Fine motor	97.0±12.8	0 (-0.4, 0.5)	0.872	0.4 (-0.7, 1.4)	0.504	-0.1 (-0.7, 0.5)	0.748	0.492
Adaptive	113.4±9.9	0.1 (-0.2, 0.4)	0.668	0.4 (-0.3, 1.2)	0.273	-0.1 (-0.5, 0.4)	0.721	0.293
Language	112.8±14.8	0.3 (-0.2, 0.7)	0.304	1.0 (-0.1, 2.2)	0.082	-0.1 (-0.7, 0.6)	0.837	0.131
Interpersonal	104.4±12.5	0.2 (-0.1, 0.6)	0.210	1.0 (0.1, 2.0)	0.030	-0.1 (-0.6, 0.4)	0.779	0.059
Temperament scores of CTTS
Activity level	3.2±0.6	0 (0, 0)	0.941	0 (-0.1, 0)	0.186	0 (0, 0)	0.372	0.140
Biological rhythms	2.6±0.6	0 (0, 0)	0.799	0 (-0.1, 0)	0.126	0 (0, 0)	0.391	0.104
Approach-withdrawal	3.0±0.8	0 (-0.1, 0)	0.026	-0.1 (-0.1, 0)	0.015	0 (0, 0)	0.586	0.080
Adaptability	2.9±0.7	0 (-0.1, 0)	0.009	-0.1 (-0.1, 0)	0.002	0 (0, 0)	0.623	0.023
Intensity of reaction	3.9±0.6	0 (0, 0)	0.281	0 (-0.1, 0)	0.084	0 (0, 0)	0.885	0.141
Mood	2.6±0.6	0 (0, 0)	0.298	0 (-0.1, 0)	0.636	0 (0, 0)	0.462	0.955
Persistence	2.8±0.6	0 (0, 0)	0.355	0 (-0.1, 0)	0.267	0 (0, 0)	0.882	0.402
Attention	3.8±0.6	0 (0, 0)	0.478	0 (0, 0.1)	0.779	0 (0, 0)	0.594	0.992
Sensitivity	3.9±0.7	0 (0, 0)	0.854	0 (-0.1, 0.1)	0.833	0 (0, 0)	0.970	0.877

Regression	Unadjusted effect of GWG		Adjusted effect of GWG
Regression	β (95%CI)	P value	β (95%CI)	P value
Single linear regression	-0.1 (-0.2, 0.1)	0.423	-0.1 (-0.2, 0.1)	0.397
Piece-wise linear regression
β1 (GWG<17.5 kg)	0.1 (-0.1, 0.4)	0.222	0.1 (-0.1, 0.3)	0.311
β2 (GWG≥17.5 kg)	-0.4 (-0.7, -0.1)	0.019	-0.4 (-0.7, -0.1)	0.024
Likelihood ratio test P value		0.026		0.026