Table 3.

Multivariate Hierarchical Linear Model Results: Conditional Growth Curves of Intimate Relationship Quality Predicted by Breastfeeding

	Mothers				Fathers
y=marital quality	Estimate	SE	95% CI	p	Estimate	SE	95% CI	p
Level (centered at 54 months of age)
Intercept	3.631	0.176	3.29, 3.98	<0.001	3.595	0.223	3.16, 4.03	<0.001
Breastfeeding ≤4 months	−0.179	0.070	−0.32, −0.04	0.011	0.006	0.082	−0.16, 0.17	0.946
Breastfeeding ≥5 months	−0.159	0.074	−0.31, −0.01	0.033	0.049	0.087	−0.12, 0.22	0.574
Slope
Intercept	0.095	0.062	−0.03, 0.22	0.129	0.128	0.075	−0.02, 0.27	0.087
Breastfeeding ≤4 months	0.059	0.028	0.004, 0.11	0.034	−0.017	0.028	−0.07, 0.04	0.537
Breastfeeding ≥5 months	0.059	0.029	0.001, 0.12	0.045	−0.035	0.028	−0.09, 0.02	0.220
Quadratic
Intercept	−0.010	0.005	−0.02, 0.0006	0.065	−0.011	0.006	−0.02, 0.0007	0.065
Breastfeeding ≤4 months	−0.005	0.003	−0.010, 0.0005	0.075	0.001	0.003	−0.004, 0.006	0.644
Breastfeeding ≥5 months	−0.004	0.003	−0.010, 0.0009	0.103	0.003	0.003	−0.003, 0.008	0.329

n=986 couples. df=973 for all tests. Covariates in the model include study site, maternal race and ethnicity, maternal age, maternal education, maternal partner status at 1 month, family income-to-needs ratio at 1 month, child sex and birth order, and early relationship quality levels.