Taking progesterone in early pregnancy

Progesterone is a hormone that plays an important role in the menstrual cycle and in maintaining a pregnancy in the early stages. If you have miscarried before and are bleeding in early pregnancy, you may benefit from taking progesterone.

On this page:

What is progesterone?

Who can progesterone help?

What else is progesterone used for?

How effective is progesterone treatment?

Will taking progesterone affect my baby?

Where can I get progesterone treatment?

What happens at the hospital or Early Pregnancy Unit?

How do I take progesterone?

Stopping progesterone at 16 weeks

What if I am not offered progesterone?

What if I’m bleeding and more than 12 weeks pregnant?

What if I have a miscarriage after taking progesterone?

Medication in pregnancy

What is progesterone?

Progesterone is a hormone that plays an important role in the menstrual cycle and in  the early stages of pregnancy.

Our bodies make progesterone. It is made in the ovaries and tells the lining of the womb to grow. If you get pregnant, the fertilised egg attaches to this thickened lining. If you do not become pregnant, the womb sheds this thickened lining, which is passed during your period.1

Progesterone also helps your body maintain your pregnancy in the early stages. It helps to prevent miscarriage.  

You can increase your progesterone levels by taking it as a supplement. You will only need to do this if you have been prescribed it by a doctor for a particular reason.

Who can progesterone help?

Research has shown that taking progesterone may prevent a miscarriage if you:

• are bleeding in early pregnancy (before 12 weeks) and
• you have had 1 or more miscarriages before.

This research also showed that progesterone is not effective if you take it  

• before you get pregnant or
• during pregnancy if you do not have both vaginal bleeding and a history of miscarriage.

The National Institute for Health and Care Excellence (NICE) says you should be offered progesterone if:

• you are bleeding in early pregnancy (before 12 weeks) and
• you have had a miscarriage before and
• your pregnancy is checked and  in the right place in the womb (uterus) by an ultrasound scan.

Progesterone is not an effective treatment for women and birthing people with an ectopic pregnancy or a pregnancy of unknown location (PUL). Sadly, it is not possible to save these types of pregnancies.

What else is progesterone used for?

If you are under the care of a recurrent miscarriage clinic, your doctor may offer progesterone supplements from day 21 of your menstrual cycle. They will only do this if tests show that your ovaries are not releasing enough progesterone (also called luteal phase hormonal insufficiency). If your pregnancy test is positive during that cycle, the progesterone supplements will be continued until 12 weeks.

Progesterone is also used in fertility treatment and for women and birthing people at risk of preterm labour.

How effective is progesterone treatment?

If you have had 1 or 2 miscarriages, taking progesterone in early pregnancy may increase your chances of having a successful pregnancy by 5%.

If you have had 3 or more miscarriages (recurrent miscarriage), taking progesterone in early pregnancy may increase your chances of having a successful pregnancy by 15%.

Will taking progesterone affect my baby?

The current guidelines tell us that there is no evidence of harm to a women or birthing person or their baby. They also say there is not enough evidence to totally rule out rare events.

The National Institute for Health and Care Excellence (NICE) reviews all the research and publish treatment guidelines. The studies show progesterone will increase your chance of a successful pregnancy. You can read more about this evidence here. When writing treatment guidelines, NICE considers possible negative effects. They balance any possible risks with the benefits of treatment.  

They will not recommend a treatment if:  

• there is good evidence of a high risk of harm to the woman or birthing person or their baby, and
• the harm caused by the treatment would be greater than the positive impact of the treatment.

A few people have asked us whether there is a link between taking progesterone and autism. There have been some small research studies in this area, but they contradict each other. This means there is no good evidence to suggest a link

As with any treatment in pregnancy, it’s impossible to predict every long-term outcome.

Where can I get progesterone treatment?

If you are bleeding or spotting, contact your GP surgery or local GP walk-in service. They may refer you to an Early Pregnancy Unit (EPU) if needed. The EPU should be able to prescribe progesterone for you if you meet the criteria.

Some EPUs offer a self-referral or walk in service. This means you can contact them yourself and don’t need to go through your GP. You will need to tell them you have had a miscarriage before.

You can also contact NHS 111 at any time of day, and they will refer you to the most appropriate service.

If you are bleeding heavily or in a lot of pain, go straight to your local accident and emergency department (A&E).

What happens at the hospital or Early Pregnancy Unit?

A doctor, nurse or midwife will talk to you about your symptoms and explain what will happen next. They will also carry out tests, including an ultrasound scan. This is to check that the pregnancy is in the womb and there is a heartbeat.

If it’s very early in your pregnancy, it may be too soon to see a heartbeat. NICE guidelines say that, as long as the pregnancy is in the womb, progesterone can be started straight away.

If you have to wait for a scan, ask for progesterone to take until then. Some may insist you have the scan first, but it is worth asking.  

If the scan is unclear (inconclusive), you will be offered another scan in 2 weeks. For example, if there are signs of a pregnancy in the womb (uterus) but it’s not the right size for the dates of your menstrual cycle.  

As long as the scan shows a pregnancy in the womb, the EPU should prescribe progesterone until just after the second scan is booked.  

After the second scan, they will either give you another prescription until you are 16 weeks pregnant, or write to your GP and ask them to prescribe it. To avoid missing any doses, ask your EPU for a copy of the letter before you leave and take it to you GP surgery, just in case.

How do I take progesterone?

You will probably be given progesterone as vaginal pessaries (400mg twice daily). This is a tablet that comes with an applicator that you use to put it high up in your vagina. Some people are given rectal pessaries instead or as well. You insert these into your bottom.

You use the pessaries from the time you have vaginal bleeding up to 16 weeks of pregnancy.

Stopping progesterone at 16 weeks

NICE guidelines recommend taking progesterone until you are 16 weeks pregnant. This is because the research gave participants progesterone up until 16 weeks of pregnancy. But people have told us they are unsure about the safest way to stop taking it.

There has been no research that compares stopping progesterone gradually between 14 - 16 weeks with stopping suddenly at 16 weeks. Different clinics take different approaches. It’s OK to talk to your doctor or midwife if you would prefer one way or the other.

You may hear about people who are taking progesterone after 16 weeks of pregnancy. After 16 weeks of pregnancy, progesterone is used to treat women and birthing people who are at risk of premature birth. There is no evidence to suggest that taking progesterone after 16 weeks helps prevent miscarriage.

You may be reassured to know that many experts think that progesterone is most important in the first 9-12 weeks of pregnancy, before the placenta has developed and takes over producing progesterone, along with the ovaries.

What if I am not offered progesterone?

Tell your doctor or midwife that NICE guidelines recommend progesterone for people with your pregnancy history. Let them know that this is what you want.

If you are still being refused treatment, you can:

• ask to speak to another healthcare professional (your GP or another clinician at the unit)
• ask to be referred by your GP to another EPU close to you.

You can bring this download with you, which explains the evidence behind the use of progesterone.

What if I’m bleeding and more than 12 weeks pregnant?

If you have bleeding later in your pregnancy, contact the hospital maternity unit immediately so you can be checked.

We don’t have enough evidence to say that the risk of miscarriage is reduced if progesterone supplements are started after 12 weeks of pregnancy and taken up to 16 weeks. Some hospitals may prescribe it to you anyway, but not all.  

What if I have a miscarriage after taking progesterone?

Some people have told us they are worried that if they did have a miscarriage, the progesterone would stop any miscarriage symptoms and lead to a missed miscarriage. We don’t know if this is the case at the moment. Our researchers should have an answer soon.  

Even if this is the case, most people would probably decide that they would still rather take progesterone and reduce the risk of having a miscarriage at all.  

Medication in pregnancy

If you do take progesterone during pregnancy, you may like to record this on the Best Use of Medicine in Pregnancy (BUMPS) website. This helps researchers understand how medicines affect the health of pregnant women and birthing people and their babies.