The new guidance, from the health watchdog NICE (National Institute for Health and Care Excellence) states that women who experience bleeding in early pregnancy and have had at least one miscarriage should be treated with the hormone progesterone.

This is based on research suggesting the treatment could lead to 8,450 more births each year in the UK.

About one in four pregnancies ends in miscarriage – the vast majority in the first few months or trimester.

How does it work?

Progesterone helps prepare the womb for the growing baby, and the more miscarriages a woman had, the more effective progesterone was, the trial found.

About one in five women experience bleeding, or spotting, in the first 12 weeks of pregnancy.

It often causes no problems but should always be checked out with a doctor or midwife to be sure.

Some women may experience a “threatened miscarriage”, where bleeding continues along with the pregnancy.

Most are told to go home and wait and see what happens next but the new National Institute for Health and Care Excellence (NICE) guidance recommends inserting progesterone pessaries into the vagina twice a day.

A trial carried out by researchers at the Tommy’s National Centre for Miscarriage Research which the new guidance is based on, found that progesterone didn’t make much of a difference for women who just had bleeding and no previous miscarriages.

But the more miscarriages a woman had suffered, the more effective progesterone was.

However, it is important to realise that only some miscarriages can be prevented by progesterone as there are other causes for miscarriages.

Royal College of Obstetricians and Gynaecologists president Dr Edward Morris said: “It is positive that NICE has acknowledged the latest evidence.

“We do, however, still have a way to go before understanding the best treatments for women experiencing unexplained pregnancy loss and would welcome further research in this area.”