TABLE 4.
Adipokine levels at 3 years postpartum, comparing women who never breastfed, whose breastfeeding was curtailed, or who breastfed successfully:* predicted values† from linear regression models
| n | Never breastfed | Curtailed breastfeeding, problems with milk supply* | Curtailed breastfeeding, no problems with milk supply* | Successful breastfeeding* | P‡ | |
|---|---|---|---|---|---|---|
| Leptin (ng/mL) (n) | 69 | 67 | 45 | 383 | ||
| Unadjusted | 564 | 11.2 (9.7–12.6)§ | 7.9 (6.4–9.3) | 9.0 (7.2–10.8) | 8.7 (8.1–9.3) | <0.01 |
| Multivariable adjusted | 564 | 8.9 (7.6–10.1)§ | 6.8 (5.6–8.1) | 7.5 (6.0–9.0) | 8.0 (7.1–8.8)§ | 0.05 |
| Adiponectin (μg/mL) (n) | 70 | 67 | 45 | 384 | ||
| Unadjusted | 566 | 19.0 (17.0–21.0) | 21.3 (19.2–23.3) | 19.9 (17.4–22.4) | 20.2 (19.4–21.1) | 0.50 |
| Multivariable adjusted | 566 | 20.9 (18.6–23.3) | 22.7 (20.3–25.1) | 21.3 (18.5–24.1) | 21.2 (19.7–22.8) | 0.58 |
| Ghrelin (pg/mL) (n) | 17 | 23 | 20 | 117 | ||
| Unadjusted | 177 | 574.7 (427.9–721.5)‖ | 718.9 (592.7–845.1) | 682.2 (546.8–817.5) | 775.7 (719.8–831.6) | 0.07 |
| Multivariable adjusted | 177 | 721.8 (566.6–877.1) | 774.0 (645.4–902.5) | 713.4 (568.5–858.3) | 824.4 (736.3–912.4) | 0.18 |
| PYY (pg/mL) (n)¶ | 17 | 23 | 21 | 116 | ||
| Unadjusted | 177 | 53.4 (45.7–62.4) | 57.5 (50.4–65.7) | 56.5 (49.2–65.0) | 60.2 (56.7–63.9) | 0.48 |
| Multivariable adjusted | 177 | 52.3 (43.0–63.5) | 57.0 (48.5–67.0) | 58.8 (49.1–70.3) | 60.9 (54.5–68.0) | 0.33 |
Data from 570 participants in Project Viva who presented for follow-up at 3 years postpartum without an intervening birth.
*We used data on mothers’ intended duration of breastfeeding, as reported at 28 weeks of pregnancy to define curtailed breastfeeding as either 1) weaning prior to 3 months among women who planned to breastfeed for more than 3 months or 2) introduction of formula prior to 3 months among women who planned to breastfeed exclusively for at least 3 months. At the 6-month interview, mothers who had weaned or were supplementing identified reasons for introducing formula or weaning from a structured list. We classified women as having problems with milk supply if they endorsed any of the following: “I wasn’t producing enough breast milk to satisfy my baby,” “I had difficulty or didn’t like pumping breast milk,” or “My baby was not gaining enough weight with breastfeeding.”
†For the multivariate-adjusted model, data presented are mean predicted values for a participant with a prepregnancy BMI of 25.1 kg/m2, the mean for the study population, modeled using a three-knot quadratic spline model for BMI. This participant was a white woman aged 35–40 years, has two children, has no parental history of diabetes, had normal glucose tolerance, is a nonsmoker, and gained 15 kg during the index pregnancy.
‡Partial F test P values for differences among categories.
§P < 0.05 vs. curtailed breastfeeding problems with supply group.
‖P < 0.05, vs. successful breastfeeding group.
¶Results presented for PYY are geometric means. Because this outcome was not normally distributed, it was modeled on the log scale. Predicted values are exponentiated for presentation to improve interpretability.