Table 2.
Mean age difference (in months) at attaining pubertal milestone for each 1-unit increase in birth weight Z-score
| Pubertal milestone | na | Unadjusted age difference | Adjusted age difference (95% CI)b |
|---|---|---|---|
| Boys | |||
| Tanner genital stage 2 | 6927 | −0.4 | −0.5 (−0.9–0.0) |
| Tanner genital stage 3 | 6927 | −0.4 | −0.4 (−0.8–0.1) |
| Tanner genital stage 4 | 6927 | −0.3 | −0.3 (−0.8–0.1) |
| Tanner genital stage 5 | 6927 | −0.6 | −0.6 (−1.3–0.0) |
| Tanner pubic hair stage 2 | 6931 | −0.2 | −0.2 (−0.6–0.3) |
| Tanner pubic hair stage 3 | 6931 | −0.3 | −0.2 (−0.6–0.2) |
| Tanner pubic hair stage 4 | 6931 | 0.0 | 0.0 (−0.4–0.3) |
| Tanner pubic hair stage 5 | 6931 | −0.2 | −0.2 (−0.7–0.3) |
| Axillary hair | 6936 | 0.4 | 0.5 (0.0–1.0) |
| Acne | 6936 | 0.6 | 0.4 (−0.1–0.8) |
| Voice break | 6742 | −0.1 | −0.2 (−0.7–0.2) |
| Adult voice | 6742 | 0.4 | 0.4 (−0.4–1.1) |
| First ejaculation | 6923 | −0.3 | −0.3 (−0.7–0.2) |
| Girls | |||
| Tanner breast stage 2 | 7348 | −0.4 | −0.2 (−0.8–0.4) |
| Tanner breast stage 3 | 7348 | 0.4 | 0.6 (0.2–1.0) |
| Tanner breast stage 4 | 7348 | 0.3 | 0.6 (0.2–1.0) |
| Tanner breast stage 5 | 7348 | 0.2 | 0.6 (−0.2–1.4) |
| Tanner pubic hair stage 2 | 7349 | 0.7 | 0.6 (0.3–1.0) |
| Tanner pubic hair stage 3 | 7349 | 0.7 | 0.8 (0.5–1.2) |
| Tanner pubic hair stage 4 | 7349 | 0.8 | 0.9 (0.5–1.4) |
| Tanner pubic hair stage 5 | 7349 | 0.8 | 1.0 (0.4–1.6) |
| Axillary hair | 7354 | 0.9 | 0.9 (0.5–1.4) |
| Acne | 7354 | 1.1 | 1.0 (0.5–1.5) |
| Menarche | 7346 | 0.7 | 0.9 (0.6–1.2) |
Notes: aNumber of observations in adjusted analyses. Numbers vary since some children did not provide information on all outcome variables. bAdjusted for parity, maternal age at menarche, maternal pre-pregnancy BMI, maternal smoking during first trimester, and highest educational class of parents.
Abbreviations: AGA, appropriate-for-gestational age; BMI, body mass index; LGA, large-for-gestational age; n, number; SGA, small-for-gestational age.