PMC full text:
Published online 2016 Mar 8. doi: 10.1289/ehp.1510065
Table 1
Selected characteristics of 706 mothers and their infants from a New Hampshire pregnancy cohort for all participants and by maternal prepregnancy weight status.a
| Variable | All (n = 706) | Normal weight (n = 406) | Overweight/obese (n = 300) | p-Valueb |
|---|---|---|---|---|
| Prepregnancy BMI (kg/m2) (mean ± SD) | 25.3 ± 4.9 | 22.1 ± 1.6 | 29.8 ± 4.4 | < 0.001 |
| Maternal age (years) (mean ± SD) | 31.1 ± 4.7 | 31.4 ± 4.7 | 30.6 ± 4.7 | 0.03 |
| Education level [n (%)]c | ||||
| Less than 11th grade | 8 (1.1) | 3 (0.7) | 5 (1.7) | 0.01 |
| High school graduate or equivalent | 68 (9.7) | 34 (8.4) | 34 (11.4) | |
| Junior college graduate, or some college or technical school | 153 (21.8) | 77 (19.1) | 76 (25.4) | |
| College graduate | 275 (39.1) | 157 (38.9) | 118 (39.5) | |
| Postgraduate schooling | 199 (28.3) | 133 (32.9) | 66 (22.1) | |
| Previous pregnancies [n (%)]d | ||||
| 0 | 281 (39.9) | 172 (42.6) | 109 (36.3) | 0.04 |
| 1 | 271 (38.5) | 151 (37.4) | 120 (40.0) | |
| 2 | 96 (13.6) | 58 (14.4) | 38 (12.7) | |
| ≥ 3 | 56 (8.0) | 23 (5.7) | 33 (11.0) | |
| Smoking status [n (%)] | ||||
| Never | 624 (88.4) | 357 (87.9) | 267 (89.0) | 0.58 |
| Evere | 45 (6.4) | 29 (7.1) | 16 (5.3) | |
| Current | 37 (5.2) | 20 (4.9) | 17 (5.7) | |
| Maternal gestational weight gain (lbs) (mean ± SD)f | 32.0 ± 12.1 | 33.8 ± 9.6 | 29.5 ± 14.5 | < 0.001 |
| Maternal gestational hyperglycemia [n (%)]g | ||||
| Normal | 566 (83.0) | 332 (84.7) | 234 (80.7) | 0.37 |
| IGT | 70 (10.3) | 37 (9.4) | 33 (11.4) | |
| GDM | 46 (6.7) | 23 (5.9) | 23 (7.9) | |
| 1-Hr blood glucose challenge test resultsg (mg/dL) (mean ± SD) | 113 ± 28 | 112 ± 27 | 114 ± 29 | 0.29 |
| Home water arsenic concentration (μg/L) [median (IQR)] | 0.5 (0.1–2.7) | 0.5 (0.1–2.6) | 0.5 (0.1–2.8) | 0.94 |
| Any seafood in 2 days before urine collection [n (%)] | 112 (15.9) | 69 (17.0) | 43 (14.3) | 0.39 |
| Any rice in 2 days before urine collection [n (%)] | 163 (23.1) | 102 (25.1) | 61 (20.3) | 0.16 |
| Urinary arsenic concentration (μg/L) [median (IQR)] | ||||
| Inorganic arsenic (iAs) | 0.3 (0.1–0.5) | 0.2 (0.1–0.5) | 0.3 (0.1–0.5) | 0.49 |
| Monomethylarsonic acid (MMA) | 0.3 (0.1–0.5) | 0.3 (0.1–0.5) | 0.3 (0.1–0.6) | 0.41 |
| Dimethylarsinic acid (DMA) | 2.8 (1.4–4.9) | 2.5 (1.3–4.8) | 2.9 (1.4–5.1) | 0.27 |
| Total Arsenic (iAs + MMA + DMA) | 3.4 (1.7–6.0) | 3.3 (1.6–5.7) | 3.6 (1.8–6.1) | 0.34 |
| Primary methylation index (MMA/iAs) | 1.0 (0.5–1.8) | 1.0 (0.5–1.8) | 1.0 (0.5–1.8) | 0.84 |
| Secondary methylation index (DMA/MMA) | 10.4 (7.6–18.3) | 10.3 (7.6–17.7) | 10.6 (7.5–18.6) | 0.68 |
| Infant delivery mode [n (%)] | ||||
| Vaginal | 472 (66.9) | 291 (71.7) | 181 (60.3) | < 0.01 |
| Cesarean section | 234 (33.1) | 115 (28.3) | 119 (39.7) | |
| Infant birth outcomes | ||||
| Gestational age (weeks) (mean ± SD) | 39.5 ± 1.6 | 39.6 ± 1.5 | 39.3 ± 1.7 | 0.02 |
| Head circumference (cm) (mean ± SD) | 34.7 ± 1.7 | 34.5 ± 1.8 | 34.9 ± 1.7 | < 0.01 |
| Birth length (cm) (mean ± SD) | 50.9 ± 2.7 | 50.9 ± 2.6 | 50.9 ± 2.8 | 0.92 |
| Birth weight (g) (mean ± SD) | 3,462 ± 516.8 | 3,435 ± 488.6 | 3,499 ± 551.5 | 0.11 |
| Ponderal index (kg/m3) (mean ± SD) | 26.3 ± 3.4 | 26.1 ± 3.3 | 26.6 ± 3.6 | 0.07 |
| Birth weight status [n (%)]h | ||||
| Small for gestational age | 37 (5.2) | 24 (5.9) | 13 (4.3) | 0.02 |
| Average for gestational age | 600 (85.0) | 353 (87.0) | 247 (82.3) | |
| Large for gestational age | 69 (9.8) | 29 (7.1) | 40 (13.3) | |
| aNormal weight defined as prepregnancy BMI 18.5–24.9 kg/m2 and overweight/obese defined as prepregnancy BMI ≥ 25 kg/m2; 25 underweight mothers (BMI < 18.5 kg/m2) excluded from analysis. bCalculated from an unpaired, 2-tailed t-test with an equal variance assumption to analyze the difference in means, a chi-square test to analyze the difference in proportions, or a Wilcoxon–Mann–Whitney test to analyze the difference in medians by maternal weight status. cEducation data missing for 3 participants. dParity data missing for 2 participants. eParticipants who reported ever smoking but did not report smoking during pregnancy or had missing data for smoking during pregnancy were classified as ever smokers. fData for gestational weight gain available for a subset of 639 women. gMaternal hyperglycemia measured as part of usual prenatal care. Results for 1-hr blood glucose screening and IGT status available for a subset of 680 women; data on GDM status available for a subset of 682 women. hAge- and sex-adjusted birth weight percentiles were used to classify infants’ size-for-gestational age, which included small (≤ 10th percentile) (SGA), average (11–89th percentile) (AGA), and large-for-gestational age (≥ 90th percentile) (LGA) (Fenton et al. 2013). | ||||