Growth hormone
This is normally secreted in pulses during stages 3 and 4 NREM sleep, although its secretion may precede sleep. Between one-half and two-thirds of the total quantity is released during the first NREM sleep episode _[20]. Its secretion is inhibited by awakening from sleep. In women the relationship with NREM sleep is less close than in men, probably because of progesterone production in the luteal phase of the menstrual cycle.

Prolactin
There is a slight circadian influence on prolactin secretion, but it is more closely related to the sleep–wake state. Its secretion is promoted by NREM sleep, particularly stages 3 and 4, but its peak plasma concentration is reached later than with growth hormone at around 90min after sleep onset. It is secreted in pulses throughout the NREM sleep cycles but is suppressed by nocturnal awakenings. Prolactin promotes REM sleep.

Renin and aldosterone
Aldosterone levels rise during REM sleep, whereas renin is secreted mostly in stages 1 and 2 NREM sleep, and it is inhibited by REM sleep.

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
These gonadotrophins are secreted in pulses during the night.

The serum concentration of LH is low, both during wakefulness and during sleep in prepubertal children, but around puberty there is release of LH in pulses during sleep associated with a corresponding rise in testosterone. By the time that sexual maturation has been reached the secretion of LH during wakefulness is similar to that during sleep. Testosterone blood levels are highest in REM sleep.