Morning wood: what it says about your health

Morning wood, waking up with an erection, is a normal part of sleep. Doctors still ask about it: sleep erections happen without any sexual stimulation, so they show whether the physical side of erections is working. Losing them can matter too: in middle-aged and older men, poor morning erections have been linked with low testosterone and with poorer health.

What is morning wood?

Morning wood is slang, and its meaning is simple: an erection you wake up with. The medical name for sleep erections is nocturnal penile tumescence (NPT). The International Society for Sexual Medicine (ISSM) says men typically have 3 to 5 in 8 hours of sleep; you may wake with one if you wake during or just after REM sleep.

Why do men get morning wood?

They come with REM (rapid eye movement) sleep. Involuntary sleep-related erections happen naturally during this stage of sleep, according to a review in Sleep Medicine Reviews. The ISSM says they're linked to activity in certain areas of the brain during REM and aren't caused by sexual stimulation.

Hormones play a part. The British Society for Sexual Medicine lists loss of early morning erections among the three most common symptoms of testosterone deficiency, and NICE notes that men with a confirmed deficiency may benefit from testosterone treatment, which should improve night-time erections.

Is it unhealthy not to get morning wood?

A morning without an erection isn't necessarily a concern, the ISSM says, because you may simply wake at a point in your sleep cycle when an erection isn't happening. It does suggest mentioning any change in your morning erections to your doctor.

If you still get erections during sleep but struggle during sex, the ISSM says the cause is more likely psychological, because the physical "plumbing" is still in working order. If you don't, it says physical issues may be the root of the problem. NICE's guidance for GPs says something similar: a sudden start, with good-quality erections that happen on their own or when you masturbate, points towards a psychological cause. The NHS page on erectile dysfunction says that, depending on the cause, you may still be able to get an erection at other times, such as when you wake up.

What morning erections can and can't tell you

	What it may mean.	What to do.
Erections on waking, but problems during sex	The physical side is probably working, so a psychological cause such as stress or anxiety is more likely (ISSM, NICE)	See a GP or a sexual health clinic if the problems keep happening
No morning erections, and problems during sex	A physical cause may be behind it (ISSM)	See a GP: the NHS says erection problems that keep happening might be a sign of a treatable condition
Fewer or softer morning erections as you get older	Common in healthy men: in a 1988 study, sleep erections became fewer and shorter with age, and most men over 60 did not have full ones	Mention any change to your doctor (ISSM)
Fewer morning erections, a low sex drive and erection problems together	The three symptoms most closely tied to low testosterone (European Male Ageing Study)	Ask a GP about a testosterone blood test
An erection that lasts more than 3 to 4 hours	Priapism, which can cause permanent damage to the penis (NHS)	Call 999 or go to A&E

Morning erections are one clue among several: the ISSM says doctors also look at your medical history, testosterone levels and any medicines you take.

Can losing morning wood be an early warning sign?

It can be a clue to your general health. The European Male Ageing Study followed 1,788 men aged 40 to 79 for an average of 12.6 years. Men who reported poor morning erections were more likely to die during that time, as were men with erectile dysfunction, while a lower sex drive wasn't linked.

The authors called sexual symptoms, especially erectile dysfunction, an early warning sign of poor health, and the link held after allowing for testosterone levels (Antonio and colleagues, Age and Ageing, 2022). The British Society for Sexual Medicine also describes loss of morning erections as a strong marker of coronary heart disease risk. These are links seen in middle-aged and older men, and they don't prove cause and effect; the ISSM also says the lack of a morning erection isn't necessarily a concern. For the heart side of the story, see erectile dysfunction: causes and what helps.

Is morning wood a sign of good testosterone?

Morning erections give a clue about testosterone, and a GP can measure it with a blood test. In the European Male Ageing Study of 3,369 men aged 40 to 79, poor morning erections, low sexual desire and erectile dysfunction were the three symptoms most closely tied to low testosterone (Wu and colleagues, New England Journal of Medicine, 2010).

In that study, men with more of the three tended to have lower levels. Testosterone falls steadily with age, by about 1% a year from around the age of 30 to 40, the NHS says, which is unlikely to cause problems in itself, and a deficiency developing later in life is uncommon. Our guide to low libido in men covers testosterone and sex drive in more detail.

Does morning wood stop when you get older?

Sleep erections happen in males of all ages, the ISSM says. They tend to become fewer and shorter as men get older. A 1975 study of 125 healthy males aged 3 to 79 found sleep erections happen consistently but are significantly affected by age (Karacan and colleagues, American Journal of Psychiatry).

A 1988 study of 40 healthy men aged 23 to 73 with no sexual problems found sleep erections became less frequent and shorter with age, whatever their sleep (Schiavi and Schreiner-Engel, Journal of Gerontology). Most men over 60 in that study did not have full sleep erections, even though they and their partners reported having sex regularly. Both studies were small and looked only at healthy men.

When should you see a GP?

See a GP or go to a sexual health clinic if erection problems keep happening, the NHS says, because it might be a sign of a health condition that can be treated. Mention a change in your morning erections too, especially alongside a low sex drive or erection problems, the pattern linked with low testosterone.

A GP can check your testosterone with a blood test. You can find a sexual health clinic near you on the NHS website. If worry about sex is part of the picture, see our guide to sexual performance anxiety in men.

Call 999 or go to A&E if you have an erection that lasts more than 3 to 4 hours, or if you have sickle cell disease and a painful erection that lasts more than 1 hour. The NHS says an erection that lasts this long needs to be treated in hospital as soon as possible to avoid permanent damage to the penis.