“We were at the edge of divorce when I decided to try this. Years and years without delight of orgasm and sexual satisfaction. This could ruin any life but not ours. Viagra worked and I always keep the pill near my bed as nobody knows when my wife asks ...

“Honeymoon returned and my husband feels like a teenager again. His erection is the same as at our first date 30 years ago. He feels like a man again, his penis is hard with a big head so he can be proud of it again. Viagra really helps.”

A doctors' group says it "borders on madness" that patients will have to obtain the note in person.

The World Health Organization's director general says no further cases have been reported since 25 May.

Despite affecting millions of women in the UK, PMOS is still under-diagnosed and inconsistently managed, say experts.

Dr Bill Kirkup says he resigned from a government-commissioned review into NHS maternity services over the omission.