Understanding arousal

When you are aroused, chemical messages and hormones are sent around your body which allow physical changes to take place such as: 

• your heart rate and blood pressure increase
• blood flows to your genitals
• your muscles tense
• your heart beats faster
• your breathing becomes faster and deeper

In people who have a vagina and vulva

Increased blood flow means your clitoris becomes bigger and more sensitive to touch, although you still might not be able to see it under its hood. Your labia swell, and you might notice that you start to get wet as your vaginal walls produce lubrication. The vagina expands in size and the uterus lifts up, which lengthens the vagina.

The image below shows some of these physical changes:
 

These physical changes prepare your body for sexual contact, and can make touch feel more comfortable and enjoyable. It is important that you give your body time to respond during the arousal process so that you don’t feel any discomfort during a sexual experience. It is also important that you feel confident talking about this with your sexual partners so they can understand and respond to your feedback about how turned on you feel. 

In people who have a penis

Increased blood flow means your genitals become more sensitive to touch and your testicles may pull up tighter to your body. The increased blood flow to the penis allows the corpus cavernosum to fill with blood, which supports to the penis to become erect.

These physical changes prepare your body for sexual contact, and can make touch feel comfortable and enjoyable. It is important that you give your body time to respond during the arousal process, so that you don’t feel any discomfort during a sexual experience. It is also important that you feel confident talking about this with your sexual partners so they understand and can respond to your feedback about how turned on you feel. 

Many people assume that sexual desire always comes before sexual arousal, but this is not necessarily the case. For example, sometimes experiencing pleasurable touch, such as kissing or massage, can start the arousal process in the body. Feeling aroused can then in turn lead to an interest in having sex.

The impact of anxiety on arousal

The arousal process is controlled by a part of the nervous system called the parasympathetic nervous system (PNS), which is an involuntary, or automatic, system that is active when our mind and body is in ‘calm’ mode. 

There is another system in the body, called the sympathetic nervous system (SNS), which works in opposition to the PNS - when one is in control, the other closes down. The SNS controls the brain and body when we feel stressed, anxious, or in danger (in ‘stress’ mode). This is sometimes called the ‘fight or flight response’. 

When the flight or fight response is activated, it sends blood to the muscles we need to run or fight (for example, our arms and legs) and shuts down all non-essential functions that we wouldn’t need if we were in danger, including the arousal system. 

The diagram below demonstrates the impact these two systems have on the body:

The fight or flight response can kick in for both real or perceived/imagined threats, meaning that worrying about something is enough to trigger these physical changes in our bodies. As shown in the diagrams, the body has to be relaxed (or in ‘calm’ mode) in order to become sexually aroused. When you’re anxious or worried (whether about being in a sexual situation or about anything else), your body switches into ‘stress’ mode which pauses the arousal system.

If anything gets in the way of the arousal process, then physical changes may not happen and your body won't be prepared for sex. This is likely to mean sex is less enjoyable, or not enjoyable at all.