Fall in nocturnal serum melatonin during prepuberty and pubescence.
Level 4 - case-series / case-control
Cross-sectional observational study measuring hormone levels across age and pubertal stages
PubMed 6141425 · doi:10.1016/s0140-6736(84)90412-4
What was done
Morning (7:30 AM to 10:00 AM) and nighttime (11:00 PM to 1:00 AM) serum melatonin concentrations, along with nocturnal luteinizing hormone (LH), were measured in 89 children, adolescents, and young adults classified by age and pubertal stage.
What was found
Morning serum melatonin levels (generally 0-20 pg/ml) did not change with sexual maturation or age. Nighttime melatonin levels decreased significantly: - Prepubertal children under 7 years: 195 +/- 24 pg/ml (mean +/- SEM) - Prepubertal children aged 7 or older: 119 +/- 23 pg/ml - Young adults (puberty stage V): 49 +/- 4 pg/ml - By age: 210 +/- 35 pg/ml (ages 1-5), 133 +/- 17 pg/ml (ages 5-11), and 46 +/- 4 pg/ml (young adults) - Nocturnal LH concentrations varied inversely with nocturnal melatonin (r = -0.35).
Why it matters
This study provides early evidence of a progressive decrease in nocturnal melatonin secretion from early childhood through puberty, linking pineal activity to the timing of human sexual maturation.
Limits
The study is cross-sectional rather than longitudinal. Blood sampling was restricted to two specific time windows rather than 24-hour profiling, and the total sample size (n = 89) is relatively small when split across multiple age and pubertal groups.
Cited by
- context Most children naturally produce approximately four times the amount of melatonin their brains require.