Women are being warned against risky cosmetic "rejuvenating" procedures to reshape and tighten the vagina.
Experts say the "therapies", offered by some private clinics in the UK and the US, pose a serious risk of burns, scarring and recurring pain.
Typically during these procedures, a probe is inserted into the vagina to heat or laser the vaginal tissue.
Although it is non-surgical and can be done in a lunch hour, it is not necessarily safe, say officials.
Laser and energy-based devices have been approved for use in destroying pre-cancerous cells in cervical or vaginal tissue, as well as genital warts, but they have not undergone testing for rejuvenation therapies.
US regulator the FDA says it will take action if deceptive marketing of the "dangerous procedure with no proven benefit" continues.
It says a growing number of manufacturers have been claiming the procedure can treat conditions and symptoms related to menopause, urinary incontinence or sexual function.
"These products have serious risks and don't have adequate evidence to support their use for these purposes. We are deeply concerned women are being harmed," says the FDA warning.
Paul Banwell, consultant plastic surgeon and member of the British Association of Aesthetic Plastic Surgeons, shared the FDA's concerns: "There has been an exponential rise in the interest in women's health and sexual well-being and whilst this should be encouraged, it is vital that any educational and treatment initiatives are provided in a sensitive manner free of any misleading or marketing hyperbole."
Dr Vanessa Mackay, from the UK's Royal College of Obstetricians and Gynaecologists (RCOG), said: "There is no evidence to suggest that non-surgical 'vaginal rejuvenation' devices are effective in improving vaginal muscle tone or reshaping vaginal tissue. If women are concerned about the appearance or feel of their vagina, they should speak to a healthcare professional. It is important to remember, however, that every woman's vagina is different. Labia are as individual as women themselves and vary in appearance and colour.
"To strengthen the muscles around the vagina, women are encouraged to try pelvic floor exercises which can help to improve muscle tone and sensitivity during sex."
How to do pelvic floor exercises:
- Sit or stand comfortably with knees slightly apart and then draw up the pelvic floor muscles as if trying to avoid passing urine
- It is important not to tighten the stomach, buttock or thigh muscles during the exercises
- Do 10 slow contractions, holding them for about 10 seconds each
- The length of time can be increased gradually and the slow contractions can then be followed by a set of quick contractions
- The whole process should be carried out three or four times a day
Vaginal dryness is a common but treatable problem that many women experience at some point in their lives.
It can be caused by a number of things including the menopause, breastfeeding, childbirth, not being aroused before sex and some types of contraception.
Women are encouraged to try self-help options before seeing a healthcare professional, including vaginal moisturisers and lubricants. If these aren't effective, a doctor may prescribe vaginal oestrogen, says the RCOG.