Table 2 Summary of the studies examining associations of maternal anthropometry with offspring cognitive function
Author, Year, Sample size, Age, Country, Study design | Maternal anthropometry | Cognitive function | Results after adjustment for confounders | QS and RB |
|---|---|---|---|---|
8Neggers YH; 2003  N = 355  Age 5.3 years  USA  Prospective Low income African- Americans; mothers participated in Zinc supplementation trial | Pre-pregnancy BMI (kg/m2) BMI 4 categories Underweight (BMI < 19.8): 6.5 % Normal (19.8-26.0): 39.2 Overweight (26.1-29.0): 14.4 % Obese(>29): 39.9 % Gestational weight gain (kg) | Differential Ability Scale –general IQ (intelligence quotient), verbal and non-verbal abilities Peabody Gross Motor Scales | ↑Pre-pregnancy BMI -↓ general IQ (β = -0.25) and non-verbal score (β = 0.29) Compared to children of normal weight mothers, children of obese mothers scored lower in general IQ (β = -4.7) and non-verbal abilities (β = -5.6) but not in verbal or motor skills Compared to children of normal weight mothers, children of underweight mothers scored lower in general IQ, verbal and non-verbal abilities but not significant No association between pregnancy weight gain and cognitive or motor skills Confounders adjusted for: Child’s BWT, GA, current age, MA, MS, maternal alcohol intake, MIQ, HE, child care status, zinc supplementation status | 14 Medium |
9Heikura U; 2008  Two birth cohorts  1966  N = 12058  Age 11.5 years  Finland  1986 birth cohort  N = 9432  Age 11.5 years  Finland | Pre-pregnancy BMI (kg/m2) BMI 4 Categories 1966 cohort Thin (BMI < 20): 13.4 % Normal (BMI 20-24.9): 65 % Overweight (BMI 25.0–29.9): 17.9 % Obese (BMI ≥30): 3.8 % 1986 cohort Thin (BMI < 20): 24.3 % Normal (BMI 20-24.9): 58.7 % Overweight (BMI 25.0–29.9): 13.1 % Obese (BMI ≥30): 3.8 % | IQ (Standardised psychometric test or clinical developmental assessment): Test battery used not reported Intellectual disability (ID)-IQ < 70 severe ID (IQ < 50) mild (IQ 50-70) | Maternal pre-pregnancy obesity predicted ID in 1986 cohort (OR = 2.8) but not in 1966 birth cohort Low BMI associated with mild ID in 1966 cohort (OR = 2.1) Interaction between parity*BMI in 1966 cohort Higher risk of ID (OR = 2.9) in children of multiparous mothers with low BMI in 1986 cohort Confounders adjusted for: MA, SES (occupation), parity, place of residence, marital status | 15 Medium |
10Tanda R; 2012  N = 3412  Age 5-7 years  USA  Longitudinal | Pre-pregnancy BMI (kg/m2) and gestational weight gain (kg) BMI 4 categories Underweight (BMI < 18.5): 7.2 % Normal (BMI 18.5-24.9): 65.6 % Overweight (BMI 25.0-29.9): 17.6 % Obese (BMI ≥30): 9.6 % | Peabody Individual Achievement Test Reading and Mathematics scores | Pre-pregnancy obesity, but not overweight, was negatively associated with cognitive skills Compared to children of normal weight mothers, children of obese mothers scored 3 points lower (0.23 SD) in reading and 2 points lower (0.16 SD) in mathematics score ↑gestational weight gain - ↓ cognitive skills but not significant Confounders adjusted for: the child’s sex, GA, current age and body size, ethnicity, parity, SES (income), MA, ME, MIQ, HE | 15 Medium |
11Hinkle SN; 2012  N = 6850  Age 2 years  USA  Population based  Longitudinal-Birth cohort | Pre-pregnancy BMI (kg/m2) and Gestational weight gain (kg) BMI 5 categories Underweight (BMI < 18.5): 5 % Normal (BMI 18.5-24.9): 56 % Overweight (BMI 25.0-29.9): 25 % Obese1(BMI 30.0-34.9): 8 %. Obese2 and 3(BMI > =35.0-39.9): 6 % | Bayley Scales of Infant Development –II (Mental Development Index (MDI) and Psychomotor Development Index (PDI)) | Compared to the children of normal BMI mothers, children of mothers in all the other categories scored lower MDI, but significant in obese2 and 3 categories (β = 2.13 points) Risk of delayed mental development (<-1SD v > 1SD) observed in children of mothers with underweight (RR = 1.36) and extreme obese (RR = 1.38) categories No association between pre-pregnancy BMI and PDI Confounders adjusted for: the child’s sex, BWT, GA, BF, MA, ethnicity, marital status, parity, DM, PIH, ME, MS, SES (income) | 16 Medium |
12Basatemur E; 2012  Age 5 years (n = 11025)  Age 7 years (n = 9882)  UK  Prospective population based birth cohort | Pre-pregnancy BMI (kg/m2) BMI continuous and categories BMI 4 categories Underweight (BMI < 18.5): 5.3 % Normal (BMI 18.5-24.9): 65.6 % Overweight (BMI 25.0-29.9): 20.1 % Obese (BMI ≥30): 9 % Excluded BMI < 16 | 5 Y-British ability scales-II Expressive language, nonverbal reasoning and spatial visualization 7 Y- British ability scales-II spatial visualization, verbal ability, and number skills test (National foundation for educational research progress in Math tests) | Children of underweight, overweight and obese mothers scored lower mean scores (0.1-0.3 SD) Maternal pre-pregnancy BMI is negatively associated with children’s general cognitive ability at 5 years (β = -0.075) and 7 years (β = -0.17) 5 years - ↑maternal BMI -↓Spatial visualization but no association with expressive language and nonverbal reasoning 7 years- ↑maternal BMI -↓Spatial visualization, verbal ability and number skills Confounders adjusted for: The child’s sex, current age, BWT, BMI, ethnicity, MA, ME, PE, SES, income, MS, DM | 15 Medium |
13Buss C; 2012  N = 174  Age 7.3 years  USA  Population based prospective  Longitudinal-Birth cohort | Pre-pregnancy BMI (kg/m2) and Gestational weight gain (kg) BMI continuous and categories BMI 3 categories Normal (BMI 18.5-24.9): 58 % Overweight (BMI 25.0-29.9): 25.9 % Obese (BMI ≥30): 16.1 % Excluded underweight mothers | Executive function Continuous Performance Task (Go/No go task) | Higher pre-pregnancy BMI (continuous and categorical) was associated with impaired performance on the Go/No go task (F1.157 = 8.37 and F2.156 = 3.57 respectively) Children of obese mothers scored higher in performance measure (higher score indicates poor performance) compared to children of normal weight mothers. No difference in scores of performance efficiency between children of obese mothers vs children of overweight/normal weight mothers (Chen’s d effect size 0.62 SD) Gestational weight gain was not associated with child performance on the Go/No go task (F1.157 = 0.27) Confounders adjusted for: The child’s sex, current age, BMI, ethnicity, GA, parity, BWT, ME, MIQ, depression, obstetric risk (PIH, DM) | 13 Medium |
14Brion M; 2011  ALSPAC: population based prospective cohort UK  N = ~5000  Age 38 months; Age 8 years  Generation R: Population based pregnancy cohort Netherlands.  N = ~2500  Age 30 Months | Pre-pregnancy BMI (kg/m2) Underweight (BMI < 18.5) Normal (BMI 18.5-24.9) Overweight (BMI 25.0-29.9) Obese (BMI ≥30) ALSPAC Normal BMI: 78.7 % Overweight/obese: 21.3 % Generation R Normal BMI: 77.9 % Overweight/obese: 22.1 % Excluded obese group (cognitive assessment at age 30-38 months) | ALSPAC-Verbal skills-MacArthur Toddler Communication Questionnaire maternal report Non-verbal skills-Diagnostic Analysis of Non-verbal Accuracy Test General intelligence-Wechsler Intelligence Scale for Children-II at 8-years Generation-R-Verbal skills-Dutch translation of the Language Development Survey Non-verbal-Dutch version of parent report of children’s abilities | ALSPAC: No association of maternal overweight with verbal and non-verbal skills. Maternal obesity was associated with ↓IQ (OR = 0.84) at 8 years Generation-R: no association between maternal overweight with verbal and non-verbal skills. Confounders adjusted for: ME, PE, occupation, income, social class (ALSPAC only), MS, BF | 15 Medium |
15Casas M; 2013  INMA: population based prospective birth cohort Spain  N = ~1967  Age 11-22 months  RHEA: Population based prospective cohort  Greece  N = 412  Age 17-20 months | Pre-pregnancy BMI (kg/m2) Underweight (BMI < 18.5) Normal (BMI 18.5-24.9) Overweight (BMI 25.0-29.9) Obese (BMI ≥30) INMA: 72.9 %, 19.2 % and 8 % normal, overweight and obese respectively RHEA: 68.3 %, 20.1 %, and 11 % normal, overweight and obese respectively Excluded underweight | INMA: Bayley Scales of Infant Development –I (Mental and Psychomotor scale) RHEA: Bayley Scales of Infant Development –III (Cognitive and fine and gross motor development scale) | Pre-pregnancy obesity, but not overweight, was negatively associated with cognitive skills Compared to children of normal weight mothers, children of obese mothers scored 2.67 points lower (INMA) and 3.57 points lower (RHEA and not significant) in mental (INMA) and cognitive development (RHEA) Cognitive score ↓ with increasing BMI (INMA -0.17 per kg/m2; RHEA -0.26 per kg/m2(not significant) No association of overweight/obesity with motor development in both cohorts Confounders adjusted for: gender, parental education, age, social class (only in INMA), maternal country of birth, breast-feeding duration, MS, employment status during pregnancy and after birth, parity, nursery attendance and main child minder | 14 Medium |
16Craig WY; 2013  Study 1- USA  Population based cohort  N = 101  Age 2 years  Study 2- USA  Population based cohort  N = 118  Age 8 years  In both studies participants were from control group of a case–control study | Pregnancy BMI (kg/m2; 2nd trimester) Normal (BMI 18.5-24.9) Overweight (BMI 25.0-29.9) Obese (BMI ≥30) Study 1: 31.6 %, 38.6 % and 29.7 % normal, overweight and obese respectively Study 2: 64.4 %, 25.4 %, and 10.2 % normal, overweight and obese respectively No underweight category | Study 1- Bayley Scales of Infant Development –III Cognitive, language and motor (gross and fine) domains Study 2-Wechsler Intelligence Scale for Children (WISC)-III Full-scale IQ, verbal and performance IQ | Study 1: ↑BMI categories- ↓scores for cognitive, language and motor domains (not significant) Percentage of children with ≥ 1 score below BSID-III score of 85 increased with BMI category and was higher among children of obese mothers compared to children of normal BMI mothers (OR 3.9) Study 2: ↑BMI categories- ↓scores for performance IQ but not for full-scale and verbal IQ Percentage of children with ≥ 1 score below WISC-III score of 85 increased with BMI category and was higher among children of obese mothers compared to children of normal BMI mothers (OR 5.2) Confounders adjusted for: gender, maternal age, smoking, number of prior births, SES (based on occupation and education) | 14 Medium |
17Huang L; 2014  N = 30212  Age 7 years  USA  Population based prospective cohort | Pre-pregnancy BMI (kg/m2) Gestational weight gain (lb) Underweight (BMI < 18.5)-9.1 % Normal (BMI 18.5-24.9)-69.2 % Overweight (BMI 25.0-29.9)-16.0 % Obese (BMI ≥30)-5.7 % | Wechsler Intelligence Scale for Children-I Full-scale, verbal and performance IQ | Pre-pregnancy obesity, but not overweight, was negatively associated with offspring IQ Compared to children of normal mothers, children of obese mothers scored 2 points lower in full-scale IQ and 2.5 points lower verbal IQ; compared to normal mothers children of underweight mothers scored ~0.6 points lower in full-scale IQ Suboptimal, inadequate or excessive weight gain in normal mothers-↓ full-scale IQ scores (~1-3 points) in children Excessive, but not inadequate, weight gain in obese mothers-↓ IQ scores in children Compared to children of normal mothers who gained 21-25 lb, children of obese mothers who gained >40 lb scored 6.5 points lower in full-scale IQ scores Confounders adjusted for: Maternal race, parity, MA, ME, MS, SES, marital status | 15 Medium |
18Tavris DR; 1982  N = 2789  Age 5 years  USA  Prospective longitudinal | Maternal gestational weight gain (difference in weight between first and last prenatal visits) 3 categories of weight gain 1) -24 to 4 lb, 2) 5 to 29 lb 3) ≥30 lb | Raven’s Coloured Progressive Matrices Details of cognitive domains assessed not mentioned | Children of mothers who gained <5 lb and >30 lb scored poorly compared to 2nd category (F = 3.23) Compared to 1st and 2nd category – no difference. Compared to 2nd and 3rd category- second category scored better (F = 4.31) Confounders adjusted for: Ethnicity, MA, parity, pre-pregnancy weight/height ratio, GA, ME, PE, income | 13 Medium |
19Gage SH; 2013  ALSPAC: population based prospective cohort-UK.  N = 5832: Age 4 years  N = 5191; Age 8 years  N = 7339; Age 16 years | Maternal gestational weight gain (kg) 3 categories of weight gain 1: less than recommended 2: As recommended 3: more than recommended Pre-pregnancy weight (kg) | School Entry Assessment Score-4 years IQ- Wechsler Intelligence Scale for Children -III-8 years Adequate final exam results-16 years | Children of women gained weight < expected-↓ school entry assessment score (-0.075 SD) and adequate final-exam results (OR = 0.88); ↑Weight gain - early and mid pregnancy -↑school entry assessment score (0.072 and 0.077 SD) ↑ Weight gain in all three periods of pregnancy-↑ IQ at 8 years (0.070 to 0.078 SD) and ↑Pre-pregnancy weight-↓ school entry assessment score (-0.004 SD/kg), IQ (-0.004 SD) and the odds (OR = 0.99) of achieving adequate final exam results Confounders adjusted for: the child’s sex, current age, MA; ME, parity, pre-pregnancy BMI, smoking and mode of delivery | 16 Medium |