Sex can be one of the most rewarding aspects of a relationship.

However for many couples, it is fraught with pain, most commonly experienced by women.

This condition, known as "dyspareunia" in medical language, is common although it is hard to know how many people it affects – estimates suggest between one and four out of every 10 women experience it, and likely far fewer men although we don't know the numbers.

There are two main types of dyspareunia for women:

* superficial, when pain is felt at the entrance to the vagina or even around the external genital area (including the labia and clitoris).

* deep, when the pain is felt much higher up, usually at the top of the vagina or in the pelvis and lower tummy area.

Superficial dyspareunia is usually felt during foreplay or initial penetration, whereas deep pain is more common later on during sex or even afterwards. Although it is very unlikely to be due to anything life-threatening, dyspareunia of any type can be really distressing, and can put a huge strain on a relationship unless it is discussed and managed appropriately.

There are many conditions that can lead to dyspareunia, and successful treatment will rely on finding out what is the cause in your particular case.

If you are experiencing pain of any sort, the following are worth considering in terms of underlying issues:

ANXIETY OR STRESS

In my experience, by far the most common factor in dyspareunia is an element of anxiety or stress. When women feel anxious, not only do the muscles around the vagina become tight, making penetration difficult and painful, but our natural lubrication also dries up, which compounds the problem.

Sometimes anxiety is the primary problem, but at other times it is secondary, caused by a previous "bad" experience of sex – this can include people who have experienced any type of sexual trauma or assault, but also people for whom their initial experiences of sex were either painful or not very satisfying. Understanding that this is a normal and very common response can be really helpful, and treating the underlying anxiety can be all that is needed to get things back on track.

INFECTION

This is another common reason for discomfort during or after sex. Infections around the vaginal opening, such as thrush, can make the skin sensitive and fragile, leading to little cracks or fissures in the tissues, and sometimes even bleeding.

Pain is felt at initial penetration. Infections higher up, including sexually transmitted infections such as chlamydia and gonorrhoea, can cause inflammation in the vagina, cervix or even in the womb and tubes. This type of infection typically causes pain with deep penetration, often felt in the lower tummy area.

SKIN CONDITIONS

Any skin problem that affects the genital area can lead to pain and discomfort. This can include conditions like eczema, dermatitis or psoriasis. This is also often an issue around the time of the menopause when the skin and tissues in the genital area become dry and less stretchy. Treating the area with topical creams is usually all that is required to restore things to normal.

ENDOMETRIOSIS

This condition not only causes painful periods, but can also cause pain with sex, typically of the "deep" type. As it can also be associated with other problems, such as difficulty getting pregnant, it is important to get it properly assessed and treated.

MEDICATION

Sadly, some medications (including contraception, acne medication, antidepressants and others) can cause sex to be uncomfortable. This is usually because they are associated with a reduction in lubrication in the genital area. Either switching to another type of medicine, or ensuring you are using good adequate lubrication, should solve this.

There are multiple other causes as well, including conditions of the gut such as irritable bowel syndrome, and scarring in the genital area as a result of surgery or traumatic childbirth. But the good news is that whatever the cause of your pain, it is nearly always treatable – so please see your GP for advice. The benefits of getting your pain sorted will far outweigh any embarrassment you might feel.

-The author is a GP and forensic medical examiner