Children come into this world with their sexual physiology ‘turned on’ and fully functioning, and the most visible proof of this is in the erections observed among little boys. Yet this still catches many new parents off guard, many of whom have bought into the myth that sexuality lies dormant until puberty. It’s especially unnerving when this occurs during a caretaker’s interaction with a child.

Is it normal for little boys to get erections?

First and foremost, erections are common at all stages of development, including infancy. Erections are first observed during prenatal development in fetuses as young as 16 weeks. One study found male fetuses have regular erections during sleep (every 90 minutes or so), just as they will throughout the rest of their life. Myss & Shealy note that when children come into this world, “Male babies are usually born with an erection and females with vaginal lubrication, indicating sexual arousal.” (1993, p. 319)

A 1978 study in Japan checked 12 full-term boys every minute for an hour and reported that 42% had at least one erection, with the longest lasting 17 minutes. A 1937 study by a Yale University professor of child development documented 1,163 ‘erection events’ when observing 9 newborns in a maternity ward over a period of 10 days. If you do the math, that works out to an average of around 18 erections per baby each day. It’s a pattern that will continue unabated throughout childhood. (Halverson, 1940; Rowe, 2007; Kinsey et al., 1947; 1953; Ford & Beach, 1951 Roiphe & Galenson, 1981)

In the early years (infancy and toddlerhood) erections are more commonly a byproduct of sensory experiences or general arousal and excitement. But as children get older they occur more frequently in response to sexual stimulus. One psychologist reports that “The six year old son of a colleague of mine told his father recently, “When I see a pretty girl my penis gets so hard!” (Martinson, 1974, p. 33) Boys often get erections when talking or playing with girls, or from close physical contact. They can also be triggered by kissing or other sexual scenes in movies, or by seeing an attractive female in a magazine or on TV. (Ramsey 1943A; 1943B)

Even more unsettling to adults is when a child sprouts an erection during physical contact with their caregivers. Parents have reported this happening during diaper changes, when bathing their children, or when dressing or undressing a little boy. Since we’re led to believe that sexuality is unnatural to childhood – and that any sort of erotic interaction with an adult is especially troublesome – the knowledge that one has inadvertently aroused a child is a tough cookie to swallow. Many caretakers have become deeply bothered by this, convinced they have done something wrong. They carry around this shameful secret, convinced that it’s a freakish or unusual event that’s horribly unnatural.

If you’re worried because this happened to you, there’s a couple things you should know. First, this type of spontaneous arousal is perfectly natural, and all children (both boys and girls) experience it repeatedly throughout childhood. Most of the time adults aren’t aware of it, and so what they don’t know can’t drive them neurotic with guilt. There’s no need to feel weird about it just because you happened to notice it this time. It’s a normal aspect of development, and no harm will come from it.

Second, it might make you feel better to know that sexual arousal can be triggered by many things that aren’t overtly sexual. Erections can be triggered by general arousal or excitement and by non-sexual stimulus like motion or movement, sensory experiences, and normal situations. So don’t freak out over a natural and harmless occurrence. Parents have enough to worry about as it is.