Table 3.

Adjusted^* Associations of Age at Menarche and Pubic Hair Development for Females and Males, Respectively, with Lung Function Measurements at 15 and 24 Years

Lung Function Outcome	Adolescence: Age, 15 Years				Early Adulthood: Age, 24 Years
	Females: Menarche† (n = 1,181)		Males: Pubic Hair‡ (n = 1,123)		Females: Menarche† (n = 943)		Males: Pubic Hair‡ (n = 529)
	β (95% CI)	P Value§	β (95% CI)	P Value§	β (95% CI)	P Value§	β (95% CI)	P Value§
FEV1, ml	−13 (−40 to 14)	0.337	−254 (−421 to −87)	0.003	28 (7 to 48)	0.009	227 (177 to 603)	4 × 10−4
FVC, ml	−8 (−35 to 19)	0.558	−335 (−516 to −154)	3 × 10−4	27 (2 to 52)	0.036	283 (26 to 540)	0.031
FEV1/FVC, %	−0.1 (−0.4 to 0.3)	0.606	0.4 (−1.3 to 2.1)	0.620	0 (−0.3 to 0.3)	0.827	2.4 (−0.1 to 4.8)	0.055
FEF25–75%, ml/s	−23 (−71 to 24)	0.331	−234 (−502 to 34)	0.869	23 (−18 to 65)	0.266	557 (195 to 919)	0.003

Definition of abbreviations: β = estimate of effect of 1-year increase in age at first menstrual bleeding for females or age at attainment of advanced pubic hair Tanner stage (>2) for males on lung function; CI = confidence interval; FEF_25–75% = forced expiratory flow, midexpiratory phase.

^*Adjusted for: lung function at age 8 years; age and height at clinic visits for spirometry; parity; maternal history of asthma or allergy; maternal smoking during pregnancy; birth weight; ever doctor-diagnosed asthma by age 14 years; exposure to smoke from birth to 8 years of age; and smoking status.

^†Age at menarche: age at the first day of the first menstrual bleeding.

^‡Age at attainment of pubic hair Tanner stage >2, estimated by parametric survival models (13) from interval-censored maternal and self-reported data collected annually on pubic hair Tanner staging.

^§P values from Wald test.