Breastfeeding and timing of pubertal onset in girls: a multiethnic population-based prospective cohort study

BMC Pediatrics

Table 2 Associations between breastfeeding duration and timing of breast development in daughters: KPNC puberty study (N=3,270)

Breastfeeding duration^a	N	TR	95% CI	HR	95% CI
Not breastfed	499	0.98	0.96–0.99	1.25	1.07–1.46
< 6 months	1102	0.99	0.98–1.00	1.09	0.97–1.22
≥6 months	1669	Ref		Ref

CI Confidence interval, HR Hazard ratio, KPNC Kaiser Permanente Northern California, TR Time ratio
^aAdjusted for maternal race/ethnicity, maternal age at delivery, education, and parity

ISSN: 1471-2431