Table 4.

Association between breast-feeding and patterns of postpartum weight change

Reference group: return to pregestational weight		PPWR			PPWG			PPWR + WG
Type of breast-feeding at 1 month*	n	RRR	95 % CI	P-value	RRR	95 % CI	P-value	RRR	95 % CI	P-value
Model 1†
No breast-feeding	61	Reference			Reference			Reference
Partial	244	0·43	0·17, 1·05	0·063	1·24	0·47, 3·22	0·665	0·64	0·33, 1·26	0·197
Predominant	25	0·65	0·15, 2·81	0·567	1·34	0·33, 5·56	0·683	0·44	0·12, 1·55	0·200
Exclusive	128	0·44	0·16, 1·19	0·104	1·23	0·45, 3·40	0·690	0·59	0·28, 1·23	0·156
Model 2‡
No breast-feeding	55	Reference			Reference			Reference
Partial	222	0·38	0·13, 1·09	0·071	1·23	0·44, 3·38	0·693	0·61	0·28, 1·33	0·214
Predominant	22	0·76	0·12, 4·61	0·761	2·18	0·47, 10·02	0·316	0·51	0·12, 2·19	0·367
Exclusive	114	0·27	0·08, 0·91	0·035	1·57	0·52, 4·72	0·419	0·69	0·29, 1·69	0·421

PPWR, postpartum weight retention; PPWG, postpartum weight gain; PPWR + WG, postpartum weight retention + weight gain; RRR, relative risk ratio.

Results from multinomial logistic regression models.

^*Type of breast-feeding at 1 month: exclusive (only breast milk), predominant (breast milk and certain liquids such as water and water-based drinks, but excluding non-human milk), partial (breast milk and any food or liquid, including non-human milk) and no breast-feeding.

^†Model 1: adjusted for age.

^‡Model 2: adjusted for age, marital status (single/separated and married/cohabitating), education (basic: elementary and secondary school; middle: high school; college: at least college), parity (primiparous and multiparous), socioeconomic status (high, middle and low), pregestational BMI (normal weight, overweight and obese), smoking history (never smokers, smokers around pregnancy and former smokers), adequacy of GWG (insufficient, adequate and excessive), gestational age at delivery and pregnancy complications (yes and no).