Table 1.
Descriptive statistics of study population stratified by periconceptional diet quality.
| Maternal characteristic | N with available data | Study population |
AHEI Q1 | AHEI Q2 | AHEI Q3 | AHEI Q4 | P-value |
|---|---|---|---|---|---|---|---|
| AHEI-2010 score (range given in parentheses) | 7997 | 55.1 ± 12.5 (22.4 - 96.9) |
39.7 ± 4.5a
(22.4 - 45.7) |
50.2 ± 2.5b
(45.8 - 54.5) |
58.9 ± 2.6c
(54.6 - 63.6) |
71.7 ± 6.2d
(63.7 - 96.9) |
<0.001 |
| Energy intake (Kcal) | 7997 | 1715.2 ± 954.2 | 1947.8 ± 939.8 | 1692.6 ± 1010.5 | 1660.0 ± 1139.7 | 1561.5 ± 600.0 | <0.001 |
| Gestational age at enrolment (weeks) | 7944 | 12.5 ± 2.7 | 12.5 ± 2.8 | 12.5 ± 1.9 | 12.6 ± 2.7 | 12.6 ± 3.2 | 0.615 |
| Maternal age (years) | 7995 | 27.3 ± 5.5 | 23.7 ± 5.1a | 26.2 ± 5.3b | 28.6 ± 5.0c | 30.6 ± 4.3d | <0.001 |
| Early pregnancy BMI (kg/m2) | 7890 | 26.2 ± 6.2 | 27.2 ± 7.2a | 26.8 ± 6.4a | 26.0 ± 5.8b | 24.8 ± 4.9c | <0.001 |
| BMI category | 7890 | ||||||
| Underweight | 179 (2.2) | 70 (3.6) | 43 (2.2) | 30 (1.5) | 36 (1.8) | <0.001 | |
| Normal weight | 4066 (50.5) | 880 (44.6) | 903 (46.1) | 1058 (53.5) | 1225 (61.8) | ||
| Overweight | 1957 (24.5) | 460 (23.3) | 533 (27.2) | 495 (25.0) | 469 (23.7) | ||
| Obese class I | 922 (11.5) | 268 (13.6) | 267 (13.6) | 231 (11.7) | 156 (7.9) | ||
| Obese class II or higher | 766 (9.6) | 293 (14.9) | 214 (10.9) | 164 (8.3) | 95 (4.8) | ||
| Race/ethnicity | 7995 | ||||||
| Non-Hispanic White | 5037 (63.2) | 965 (48.4) | 1168 (58.5) | 1384 (69.1) | 1540 (76.8) | <0.001 | |
| Non-Hispanic Black | 906 (11.3) | 479 (24.0) | 249 (12.5) | 122 (6.1) | 56 (2.8) | ||
| Hispanic | 1317 (16.5) | 398 (20.0) | 440 (22.0) | 289 (14.4) | 190 (9.5) | ||
| Asian | 336 (4.2) | 20 (1.0) | 49 (2.5) | 131 (6.5) | 136 (6.8) | ||
| Other | 379 (4.7) | 131 (6.6) | 90 (4.5) | 76 (3.8) | 82 (4.1) | ||
| Highest education received | 7994 | ||||||
| Some or completed high school | 1412 (17.7) | 782 (39.2) | 407 (20.4) | 182 (9.1) | 41 (2.0) | <0.001 | |
| Some or completed college | 4626 (57.8) | 1115 (54.9) | 1327 (64.5) | 1287 (60.6) | 1030 (65.0) | ||
| Postgraduate education | 1956 (24.5) | 116 (5.8) | 302 (15.1) | 606 (30.3) | 932 (46.5) | ||
| Below federal poverty threshold | 6647 | 955 (11.9) | 471 (34.2) | 267 (16.9) | 154 (8.6) | 63 (3.3) | <0.001 |
| Smoked tobacco prior to pregnancy | 7991 | 1336 (16.7) | 601 (30.2) | 366 (18.4) | 236 (11.8) | 133 (6.6) | <0.001 |
| Rate of GWG (kg/week) | 6292 | 1.1 ± 0.5 | 1.0 ± 0.6a | 1.1 ± 0.5 | 1.1 ± 0.6 | 1.1 ± 0.4b | 0.024 |
| Incidence of GDM | 7997 | 326 (4.1) | 89 (4.5) | 82 (4.1) | 85 (4.2) | 70 (3.5) | 0.447 |
| Elevated 1-hr glucose concentration on 50g screening test | 6845 | 992 (12.7) | 261 (15.3) | 222 (13.0) | 258 (15.1) | 251 (14.7) | 0.214 |
Data are presented as mean ± SD for continuous variables or N (%) for categorical variables, where percentage values represent the incidence of a given characteristic within each AHEI quartile. P < 0.05 indicates significant differences across AHEI quartiles, computed by one-way ANOVA for continuous variables or chi-squared test for categorical variables. Different superscript letters indicate significant difference between specific AHEI quartiles for continuous variables, assessed by post-hoc Tukey’s test. AHEI, Alternative Healthy Eating Index; GDM, gestational diabetes mellitus; GWG, gestational weight gain.