Sex is painful for more than seven percent of women, research has found.
A survey of almost 7 000 sexually active women found that anxiety and menopause were the major causes.
Those aged 55 to 64 were most likely to suffer pain during sex. For many, this can be caused by the menopause, which causes soreness because of falling hormone levels.
But being less interested than their partner may also make any encounters tense, stressful and ultimately painful.
The other age group most commonly affected was 16- to 24-year-olds, often because of inexperience.
They may be too self-conscious to tell their partner what they do not enjoy, leading to anxiety which can cause pain.
The study, in BJOG: An International Journal of Obstetrics and Gynaecology, found 7.5 percent of women reported having painful sex.
For a quarter of them, the pain had been over at least six months, occurring frequently or every time.
Many avoided sex because they were so afraid of the pain, but others simply coped with their symptoms to keep their love life alive.
The study said pain during sex leads to feelings of isolation, shame and loss of confidence.
Dr Kirstin Mitchell, who conducted the research at the London School of Hygiene and Tropical Medicine (LSHTM), said conditions such as urinary tract infections and sexually transmitted infections could make sex painful too.
She said: "For younger women, it may be related to a lack of experience or confidence, where they may feel unable to talk to their partner about what they like or dislike in bed. If they are tense because they are not enjoying sex, or feel self-conscious about their body, this can make painful sex worse. In the older age group, it is likely they may be suffering from dryness caused by hormonal changes from the menopause."
A 62-year-old women from London, who did not want to be named, said: "At about 40, I started to experience the perimenopause. It was then that I felt that my sex drive dipped quite considerably, arousal seemed to take longer, and, despite an understanding husband, I started to dread him making approaches."
The woman, who suffered difficulties in her marriage before being prescribed oestrogen by her GP, said: "Menopausal women need to know that there is help out there for these kinds of problems, especially as we are all living longer.
"Whilst I have spoken with friends about it, it’s interesting to note how many women don’t like to talk about it. We share all the gore of childbirth but menopause seems to be the last frontier."
Women in middle age can become sore during sex because of vaginal dryness, caused by a dip in oestrogen levels in the blood when they reach menopause.
The survey, by LSHTM, University College London and NatCen Social Research between 2010 and 2012, questioned women aged 16 to 74 who had sex in the previous year.
It found 10.4 percent of women aged 55 to 64 suffer pain, followed by 9.5 percent of 16- to 24-year-olds. The rate of sufferers who no longer wanted to have sex was twice that of pain-free women.
Mitchell said: "We see at any age that this is hard for women to talk about, and education and help to identify the problems is needed."