Morning erections occur when you wake up with an erection. They usually happen during the transition between REM sleep and being awake. REM is the deepest stage of sleep and occurs every 90 minutes throughout your night's rest. During this phase, brain activity increases significantly while your body is paralyzed to prevent you from acting out dreams. Testosterone levels also rise during REM, which can increase the likelihood of morning erections. This is why males who take medication that suppresses testosterone may experience less frequent or intense morning erections than those without such treatment.
The cause of morning erections is still not fully understood, but it is believed they are related to sexual arousal and brain chemistry changes during sleep. Erections occur due to increased blood flow to the penis and relaxation of muscles surrounding it. When you become sexually aroused, nerve endings in the penis release chemicals like nitric oxide that dilate blood vessels and allow more blood into the organ. In contrast, other hormones, such as vasoconstrictors, constrict blood vessels and reduce blood flow when you lose interest in sexual activity. These processes are thought to be similar during REM sleep, leading to occasional erections upon waking.
There is some evidence that morning erections are linked to overall health. Men who have low testosterone levels tend to have fewer morning erections. However, studies suggest a relationship exists between morning erections and cardiovascular health, with men who report having them experiencing lower rates of heart disease. As a result, morning erections may reflect underlying physical conditions and should not be ignored. If you consistently lack morning erections or notice other issues with sexual function, talk to your doctor for further evaluation.
Morning erections are normal and nothing to worry about unless they cause pain or discomfort. They usually last only a few minutes before subsiding on their own. There is no need to seek medical attention or take medication for them unless they interfere with daily activities or affect relationships. You can also avoid morning erections by reducing stress levels and improving sleep quality through lifestyle modifications, such as exercise, diet changes, and avoiding alcohol and nicotine.