Table 1:
Maternal Dietary Intake across Pregnancy among Women with Dichorionic Twin Pregnancies (NICHD Fetal Growth Studies – Twins)
| Dietary Variables | Weighted a Mean b (95% CI) | P c | ||
|---|---|---|---|---|
| 1st Trimester Visit n = 138 |
2nd Trimester Visit n = 121 |
3rd Trimester Visit n = 78 |
||
| Total energy (kcal) | 2010 (1846, 2175) | 2177 (2005, 2349) | 2253 (2056, 2450) | 0.01 |
| Foods and food groups (MPED servings) d | ||||
| Fruits and vegetables | 4.0 (3.6, 4.4) | 4.1 (3.7, 4.5) | 3.8 (3.3, 4.3) | 0.78 |
| Total fruits | 2.0 (1.7, 2.2) | 2.2 (1.9, 2.5) | 2.1 (1.7, 2.4) | 0.60 |
| Whole fruits | 1.4 (1.2, 1.6) | 1.6 (1.4, 1.8) | 1.4 (1.2, 1.7) | 0.60 |
| Total vegetables | 2.1 (1.8, 2.3) | 1.9 (1.6, 2.1) | 1.7 (1.5, 2.0) | 0.41 |
| Dark-green vegetables | 0.4 (0.3, 0.5) | 0.3 (0.2, 0.4) | 0.3 (0.2, 0.4) | 0.60 |
| Orange vegetables | 0.1 (0.1, 0.2) | 0.1 (0.1, 0.2) | 0.1 (0.1, 0.2) | 0.71 |
| Other vegetables | 0.8 (0.7, 0.9) | 0.7 (0.6, 0.9) | 0.6 (0.5, 0.8) | 0.60 |
| White potatoes | 0.3 (0.3, 0.3) | 0.2 (0.2, 0.3) | 0.3 (0.2, 0.3) | 0.41 |
| Starchy vegetables | 0.2 (0.1, 0.2) | 0.2 (0.1, 0.2) | 0.1 (0.1, 0.1) | 0.41 |
| Tomatoes | 0.3 (0.3, 0.4) | 0.3 (0.2, 0.3) | 0.3 (0.2, 0.3) | 0.71 |
| Whole grains | 0.9 (0.8, 1.0) | 0.9 (0.8, 1.0) | 0.9 (0.8, 1.0) | 0.95 |
| Total dairy | 1.9 (1.6, 2.2) | 1.9 (1.6, 2.2) | 2.2 (1.9, 2.6) | 0.60 |
| Milk | 1.1 (0.8, 1.4) | 1.1 (0.8, 1.4) | 1.4 (1.0, 1.7) | 0.60 |
| Cheese | 0.6 (0.5, 0.7) | 0.6 (0.5, 0.7) | 0.7 (0.6, 0.7) | 0.60 |
| Yogurt | 0.2 (0.2, 0.3) | 0.2 (0.2, 0.3) | 0.2 (0.2, 0.3) | 0.98 |
| Processed meats | 0.5 (0.4, 0.6) | 0.4 (0.3, 0.5) | 0.5 (0.3, 0.6) | 0.60 |
| Legumes | 0.1 (0.1, 0.1) | 0.1 (0.1, 0.1) | 0.1 (0.1, 0.1) | 0.98 |
| Fish | 1.2 (1.0, 1.4) | 1.2 (1.0, 1.4) | 1.0 (0.8, 1.3) | 0.60 |
| Macronutrients | ||||
| Carbohydrates (% energy) | 50.0 (48.6, 51.4) | 49.3 (47.8, 50.8) | 48.4 (46.6, 50.2) | 0.32 |
| Protein (% energy) | 16.5 (15.9, 17.1) | 16.6 (16.0, 17.2) | 16.9 (16.2, 17.6) | 0.54 |
| Total fat (% energy) | 35.5 (34.4, 36.7) | 36.3 (35.1, 37.5) | 36.8 (35.4, 38.2) | 0.32 |
| PUFA (% energy) | 7.2 (6.9, 7.6) | 7.4 (7.1, 7.8) | 7.3 (6.9, 7.8) | 0.67 |
| SFA (% energy) | 11.6 (11.1, 12.0) | 12.0 (11.5, 12.5) | 12.4 (11.9, 13.0) | 0.13 |
| MUFA (% energy) | 14.0 (13.4, 14.6) | 14.0 (13.4, 14.7) | 14.2 (13.5, 15.0) | 0.80 |
| Carbohydrates (grams) | 247.5 (239.0, 256.0) | 248.5 (239.5, 257.5) | 236.4 (225.8, 247.1) | 0.17 |
| Protein (grams) | 82.2 (78.8, 85.6) | 81.4 (77.8, 85.0) | 85.1 (81.0, 89.3) | 0.32 |
| Total fat (grams) | 79.8 (76.8, 82.8) | 80.6 (77.5, 83.8) | 83.9 (80.2, 87.5) | 0.17 |
| Added sugars (tsp equivalent)e | 14.9 (12.8, 17.0) | 15.9 (13.6, 18.1) | 12.3 (9.6, 15.1) | 0.17 |
| Total dietary fiber (grams) | 19.3 (18.0, 20.7) | 19.3 (17.8, 20.7) | 18.5 (16.9, 20.1) | 0.66 |
| Micronutrients | ||||
| Iron (mg) | 16.0 (15.3, 16.6) | 15.7 (15.0, 16.3) | 15.7 (14.9, 16.5) | 0.94 |
| Zinc (mg) | 11.7 (11.2, 12.2) | 12.2 (11.7, 12.7) | 12.0 (11.3, 12.6) | 0.49 |
| Calcium (mg) | 1004.6 (918.6, 1090.6) | 991.0 (900.1, 1082.0) | 1077.2 (971.1, 1183.3) | 0.49 |
| Potassium (mg) | 3176.3 (3017.2, 3335.5) | 3153.4 (2984.8, 3322.0) | 3189.4 (2991.8, 3387.1) | 0.94 |
| Sodium (mg) | 3192.4 (3091.8, 3293.0) | 3080.9 (2974.2, 3187.6) | 3100.1 (2974.5, 3225.7) | 0.49 |
| Total folate (μg, DFE) | 539.8 (513.6, 566.0) | 518.2 (490.6, 545.8) | 532.5 (500.6, 564.4) | 0.49 |
| Vitamin B6 (mg) | 2.0 (1.9, 2.1) | 2.0 (1.9, 2.1) | 2.0 (1.9, 2.2) | 0.94 |
| Vitamin B12 (μg) | 5.4 (5.0, 5.8) | 5.4 (4.9, 5.8) | 5.5 (4.9, 6.0) | 0.94 |
| Vitamin C (mg) | 159.0 (142.8, 175.3) | 163.6 (146.3, 181.0) | 154.2 (133.1, 175.2) | 0.94 |
| Vitamin A (μg, RAE) | 948.1 (874.2, 1022.0) | 876.2 (797.8, 954.7) | 953.2 (860.5, 1046.0) | 0.49 |
| Vitamin D (mg) | 5.8 (5.1, 6.5) | 5.7 (5.0, 6.5) | 6.1 (5.2, 7.0) | 0.94 |
| Healthy Eating Index-2010 f | ||||
| Total score (100) | 63.9 (62.1, 65.6) | 64.5 (62.6, 66.3) | 63.2 (61.1, 65.3) | 0.36 |
| Total vegetable score (5) | 3.8 (3.6,4.0) | 3.6 (3.4,3.8) | 3.5 (3.3,3.8) | 0.13 |
| Greens and beans score (5) | 2.9 (2.6,3.2) | 2.9 (2.6,3.2) | 2.9 (2.6,3.3) | 0.95 |
| Total fruit score (5) | 4.2 (4.0,4.4) | 4.3 (4.1,4.5) | 3.9 (3.7,4.2) | 0.13 |
| Whole fruit score (5) | 4.4 (4.2,4.6) | 4.5 (4.3,4.7) | 4.4 (4.1,4.6) | 0.56 |
| Whole grains score (10) | 3.2 (2.9,3.5) | 3.0 (2.6,3.3) | 3.0 (2.6,3.4) | 0.53 |
| Dairy score (10) | 6.2 (5.8,6.6) | 6.7 (6.2,7.1) | 6.9 (6.4,7.4) | 0.12 |
| Total protein foods score (5) | 4.6 (4.4,4.7) | 4.7 (4.5,4.8) | 4.5 (4.4,4.7) | 0.34 |
| Seafoods and plant proteins food score (5) | 4.0 (3.8,4.2) | 4.1 (3.9,4.3) | 4.0 (3.7,4.3) | 0.64 |
| Fatty acid ratio score (10) | 5.0 (4.5,5.5) | 4.9 (4.4,5.4) | 4.6 (4.0,5.2) | 0.56 |
| Sodium score (10) | 4.4 (3.9,4.8) | 4.9 (4.5,5.4) | 4.8 (4.3,5.3) | 0.14 |
| Refined grain score (10) | 7.9 (7.5,8.3) | 8.4 (8.0,8.8) | 8.0 (7.5,8.4) | 0.12 |
| Empty calories score (20) | 13.3 (12.5,14.1) | 12.7 (11.8,13.5) | 12.8 (11.8,13.7) | 0.32 |
Inverse probability weighting applied to the analytic sample at each trimester (n=138, n=121, n=78) to reflect the characteristics of the full cohort (n = 171). Variables used in calculating inverse probability weights included age, income, insurance, body mass index category, race/ethnicity, parity, marital status, education, nativity, twin outcomes, gestational diabetes, and hypertensive disorders of pregnancy.
All means except total energy, % energy of macronutrients, and Healthy Eating Index-2010 were adjusted for energy to 2000 kcal/day
The difference between first, second, third trimester diet was tested, and false discovery rate adjusted P-values within each dietary component section were computed
Food and food group servings/day estimated from the MyPyramid Equivalents Database (MPED) in cup equivalents for fruits, vegetables, and dairy and ounce equivalents for meat, poultry, fish, grains, and legumes
Added sugars servings/day estimated from the MyPyramid Equivalents Database (MPED) in teaspoon equivalents
Healthy Eating Index-2010 recommended scores are shown in parentheses after each component
Abbreviations - MPED: MyPyramid Equivalents Database; CI: Confidence Interval; PUFA: Polyunsaturated Fatty Acids; SFA: Saturated Fatty Acids; MUFA: Monounsaturated Fatty Acids; DFE, dietary folate equivalents; RAE, retinol activity equivalents.