TABLE 3.
Associations between dietary patterns and preterm birth: PIN study, 1996–20051
| Q1 | Q2 | Q3 | Q4 | |
| Factor 12 | ||||
| PTBs/pregnancies, n/n | 92/786 | 105/786 | 92/786 | 75/785 |
| Crude | 1.00 | 1.20 (0.88, 1.63) | 1.06 (0.77, 1.44) | 0.88 (0.63, 1.22) |
| Adjusted | 1.00 | 1.20 (0.88, 1.64) | 1.07 (0.77, 1.49) | 0.87 (0.60, 1.27) |
| Factor 23 | ||||
| PTBs/pregnancies, n/n | 80/786 | 77/785 | 99/787 | 108/785 |
| Crude | 1.00 | 0.98 (0.70, 1.37) | 1.29 (0.94, 1.78) | 1.41 (1.03, 1.93) |
| Adjusted | 1.00 | 1.01 (0.72, 1.42) | 1.37 (0.96 1.96) | 1.53 (1.02, 2.30) |
| Factor 34 | ||||
| PTBs/pregnancies, n/n | 73/785 | 87/786 | 92/787 | 112/785 |
| Crude | 1.00 | 1.24 (0.89, 1.73) | 1.33 (0.96, 1.86) | 1.62 (1.18, 2.23) |
| Adjusted | 1.00 | 1.25 (0.89, 1.74) | 1.32 (0.94, 1.86) | 1.55 (1.07, 2.24) |
| Factor 45 | ||||
| PTBs/pregnancies, n/n | 93/786 | 84/786 | 97/786 | 90/785 |
| Crude | 1.00 | 0.91 (0.66, 1.25) | 1.12 (0.82, 1.53) | 1.08 (0.79, 1.48) |
| Adjusted | 1.00 | 0.94 (0.68, 1.31) | 1.18 (0.85, 1.64) | 1.13 (0.79, 1.63) |
| DASH6 | ||||
| PTBs/pregnancies, n/n | 101/714 | 73/658 | 118/934 | 72/837 |
| Crude | 1.00 | 0.83 (0.61, 1.12) | 0.90 (0.69, 1.19) | 0.55 (0.39, 0.78) |
| Adjusted | 1.00 | 0.85 (0.63, 1.16) | 0.96 (0.72, 1.29) | 0.59 (0.40, 0.85) |
Values are ORs (95% CIs) unless otherwise indicated; n = 3143. Regression analysis for factors 1–4 includes all factors in the same model and adjusted for maternal age, race, maternal prepregnancy BMI status, educational level, household income, parity, marital status, smoking status, and energy intakes. DASH, Dietary Approaches to Stop Hypertension; PIN, Pregnancy, Infection, and Nutrition; PTB, preterm birth; Q, quartile.
Factor 1 includes high factor loadings for fruits, tomatoes, broccoli, spinach, carrots, green salads, sweet potatoes, low-fat milk, yogurt, high-fiber and highly fortified cereals, nonfried chicken and fish, and wheat bread. Quartile medians (range): Q1 = −0.85 (−1.83, −0.56), Q2 = −0.29 (−0.56, −0.03), Q3 = 0.2 (−0.03, 0.56), and Q4 = 1.0 (0.56, 2.85).
Factor 2 includes high factor loadings for beans, corn, French fries, hamburgers or cheeseburgers, white potatoes, fried chicken, spaghetti dishes, cheese dishes such as macaroni and cheese, cornbread or hushpuppies, processed meats, biscuits, and ice cream. Quartile medians (range): Q1 = −1.00 (−2.63, −0.67), Q2 = −0.37 (−0.67, −0.07), Q3 = 0.23 (−0.07, 0.57), and Q4 = 1.00 (0.57, 2.67).
Factor 3 includes high factor loadings for collard greens, coleslaw or cabbage, red meats, fried chicken and fish, processed meats, cornbread or hushpuppies, eggs or egg biscuits, gravy, whole milk, and vitamin C–rich drinks. Quartile median (range): Q1 = −0.94 (−2.20, −0.60), Q2 = −0.35 (−0.60, −0.13), Q3 = 0.14 (−0.13, 0.44), and Q4 = 0.90 (0.45, 2.92).
Factor 4 includes high factor loadings for shellfish, pizza, salty snacks, candies, pancakes, tacos or burritos, and cakes or cookies. Quartile median (range): Q1 = −0.91 (−2.30, −0.57), Q2 = −0.31 (−0.58, −0.06), Q3 = 0.23 (−0.06, 0.56), and Q4 = 1.05 (0.56, 3.18).
Quartile median (range): Q1 = 18 (9, 20), Q2 = 22 (21, 23), Q3 = 25 (24, 27), and Q4 = 30 (28, 38).