Pregnancy After Miscarriage

Progesterone is a hormone that your body naturally produces during pregnancy. It plays an important role in supporting a pregnancy, particularly in the early stages, by preparing the uterus for a fertilised egg to implant and supporting the pregnancy while the placenta develops.  

Progesterone supplementation is widely used in other areas of reproductive healthcare, including fertility treatment, contraception and hormone replacement therapy (HRT).

Around 1 in 5 pregnant women experience some bleeding or spotting. Although this can be worrying, it does not always mean that you are having a miscarriage. 

However, bleeding in early pregnancy is associated with a higher risk of miscarriage. Around 1 in 3 women who experience bleeding in early pregnancy will sadly go on to have a miscarriage. 

If you have bleeding, it is important to contact your GP or Early Pregnancy Unit (EPU) for advice.

Research has found that progesterone can increase the chance of having a baby for some women who have bleeding in early pregnancy and have had a previous miscarriage.

The benefit is greater for women who have had more previous miscarriages. However, progesterone cannot prevent every miscarriage, and unfortunately it does not help in most situations. This is because most miscarriages are caused by genetic abnormalities in the pregnancy, and progesterone cannot affect these changes.

There is currently no evidence that progesterone prevents miscarriage in people who have bleeding in early pregnancy but have not previously had a miscarriage. There is also no evidence that taking progesterone routinely prevents miscarriage if you have had previous miscarriages but do not have bleeding in your current pregnancy.

This is why progesterone is not routinely offered to everyone who has had a miscarriage.

Two large UK-based clinical trials looked at whether progesterone could help prevent miscarriage. 

The PROMISE trial: treating women with recurrent miscarriage with progesterone 

The PROMISE trial looked at 836 women who had experienced unexplained recurrent miscarriage. The study found that 65.8% of women who received progesterone went on to have a live birth, compared with 63.3% of those who received a placebo. 

Although this was a difference of 2.5 percentage points, the result was not ‘statistically significant’. This means that a similar result could have happened by chance, so the study did not provide clear evidence that progesterone prevents miscarriage when it is given routinely to women with recurrent miscarriage who are not bleeding in their current pregnancy. 

The PRISM trial: treating women with bleeding with progesterone 

The PRISM trial included 4,153 women who were experiencing bleeding in early pregnancy across 48 UK hospitals. 

Among women with bleeding in early pregnancy who had experienced one or two previous miscarriages, progesterone increased the live birth rate from 72.4% to 76.1%. (by around 4 percentage points). Although this difference was not statistically significant by itself, when adding it to other studies, the authors felt there was sufficient evidence to recommend it in this scenario.  

For women who had experienced three or more previous miscarriages (recurrent miscarriage), the evidence is stronger: progesterone increased the live birth rate from 57% to 72% (by around 15 percentage points). 

This research is why progesterone is now recommended for some women with bleeding in early pregnancy and a history of miscarriage.

Health trusts and boards in England, Wales and Northern Ireland generally follow the National Institute for Health and Care Excellence (NICE), which recommends offering progesterone if: 

• you have vaginal bleeding in early pregnancy 

• AND you have had at least one previous miscarriage 

• AND a scan has confirmed that the pregnancy is inside your uterus (an intrauterine pregnancy). 

You do not necessarily need to have seen a baby’s heartbeat before starting progesterone. NICE says progesterone can be started once a scan has confirmed that the pregnancy is in the womb. If a heartbeat is then confirmed, progesterone should normally be continued until 16 completed weeks of pregnancy. 

NICE guidelines are recommendations rather than rules that healthcare professionals must follow in every situation. Your healthcare team will consider your individual circumstances and use their clinical judgement when deciding what treatment is appropriate for you.

A scan is important because it confirms that the pregnancy is inside the uterus. This helps to make sure that progesterone is not given when there may be an ectopic pregnancy. 

If you are bleeding and have had a previous miscarriage, contact your local early pregnancy unit (EPU) and ask about having an early scan and whether progesterone is appropriate for you. 

If you have a first scan and it is not yet possible to confirm whether the pregnancy is developing in the correct place, you may be asked to come back to have another scan in a few days.  

If you’re waiting for a first or follow up scan, you can ask if you can start progesterone while you wait. Some doctors prefer to wait until a scan confirms the pregnancy is in the right place, but you can always ask. 

For more information about early pregnancy scans, click here.

Scotland has its own Progesterone Pathway, published by the Scottish Government. 

The pathway recommends progesterone for women who have had at least one previous miscarriage and have bleeding in early pregnancy, where it is clinically appropriate. 

It also provides guidance for women who have had four or more previous miscarriages but do not have bleeding in their current pregnancy. This is different from the NICE recommendations used elsewhere in the UK. 

If you live in Scotland and have experienced recurrent miscarriage, speak to your healthcare team about whether you are eligible for progesterone under the Scottish pathway.

If you have bleeding or spotting in early pregnancy, contact your GP or local Early Pregnancy Unit (EPU). 

Some EPUs allow you to self-refer or offer a walk-in service, so you may not need to see your GP first. If you have had previous miscarriages, your EPU may also have advised you to contact them as soon as you become pregnant again. 

If progesterone is appropriate for you, your EPU or another healthcare professional can prescribe it. 

Your EPU may give you an initial prescription and ask your GP to prescribe the rest of your treatment. Local arrangements vary. 

If you are given a prescription to take to your GP, it can be helpful to ask for a copy of the letter sent to your GP before you leave the EPU. This can help avoid delays in getting further medication. 

If you are bleeding heavily, have severe pain, feel faint or unwell, or are worried that something is seriously wrong, go straight to your local accident and emergency department (A&E).

The treatment recommended by NICE is 400mg of vaginal micronised progesterone twice a day. This is progesterone that is identical in structure to the progesterone naturally produced by your body and is given as a pessary, usually inserted into the vagina or sometimes rectally (into your back passage).   

You may notice increased vaginal discharge while using progesterone pessaries, or a white powder on your underwear. This is common.

If a heartbeat is confirmed, NICE recommends continuing progesterone until 16 completed weeks of pregnancy. This is because this was the duration of treatment used in the research on which the recommendation is based. 

You may hear about people gradually reducing their progesterone before stopping it. There is not enough evidence to say whether gradually reducing the dose is better than stopping at 16 weeks. If you are unsure about when or how to stop your treatment, speak to your doctor or Early Pregnancy Unit. 

You may also hear about progesterone being used after 16 weeks of pregnancy. This is generally for a different reason, such as reducing the risk of premature birth. There is no evidence that continuing progesterone beyond 16 weeks prevents miscarriage. 

Many experts believe progesterone is most important in the first 9-12 weeks of pregnancy. By then, the placenta has developed and takes over making the progesterone needed to support the pregnancy.

If you think you might be eligible for progesterone, tell your doctor, midwife or Early Pregnancy Unit about your previous pregnancies and any bleeding you are experiencing. 

You can ask: 

“Could you tell me whether I am eligible for progesterone under the current guidance?” 

If you meet the criteria but progesterone has not been discussed, you can ask your healthcare professional to explain why. 

If you are still concerned, you could ask to speak to another healthcare professional, such as another doctor at the unit or your GP. 

Depending on where you live, you may also be able to contact another Early Pregnancy Unit for advice. 

You can also see a private specialist, although you would normally need an appointment so they can review your pregnancy and medical history. You may also need a further ultrasound scan.

If you have a live pregnancy when you start progesterone and meet the criteria for treatment, you do not normally need any additional follow-up just because you are taking progesterone. Your usual antenatal care should continue as normal. 

If you start progesterone when it is not yet possible to confirm whether the pregnancy is live, you will usually be offered another ultrasound scan around 1-2 weeks later to check how the pregnancy is developing. 

Your healthcare team will tell you if you need any other appointments or scans.

Unfortunately, progesterone cannot prevent most miscarriages. Some people will still have a miscarriage even when they have taken progesterone. 

This does not mean that the progesterone has failed or that you did anything wrong. Many miscarriages happen because the pregnancy was not developing normally, often because of chromosomal problems that could not have been prevented. 

Progesterone may also delay the signs of a miscarriage, meaning you might not have the usual symptoms straight away. This can sometimes delay a diagnosis.  

The evidence available so far has not shown an increased risk of harm to women or babies from vaginal micronised progesterone used in early pregnancy. However, the studies were not large enough to rule out the possibility of very rare effects, and we do not yet have complete information about the long-term effects on children. 

You may come across reports suggesting that progesterone-type hormones could be linked to developmental differences in children. These findings are not conclusive, and the researchers themselves say more studies need to be done to understand whether any association is actually caused by progesterone or by other factors. 

If you have concerns about the possible benefits or risks of progesterone, talk to your doctor or Early Pregnancy Unit. They can help you understand how the evidence applies to your individual situation.

Researchers continue to study how and when progesterone might help prevent miscarriage. 

In Scotland, the PROTEA Study, which we are supporting, is investigating progesterone for women with early pregnancy bleeding. Researchers are looking not only at whether progesterone can prevent miscarriage, but also at whether it affects other pregnancy outcomes or complications, like pre-eclampsia, and the longer-term health of babies. 

As more research becomes available, recommendations about who should be offered progesterone may change.

Like all medicines, progesterone may cause side effects, although not everyone experiences them. Common side effects (affecting up to 1 in 10 people) may include:

• Drowsiness
• Breast tenderness
• Abdominal discomfort
• Constipation

Allergic reactions are uncommon but may include skin rash or itching. Seek medical advice if you develop any signs of an allergic reaction.

I had progesterone in a previous pregnancy that didn’t miscarry, and want to take it again in my next pregnancy even though I have not had bleeding – what can I do? 

If you had a positive outcome after taking progesterone, having had miscarriages previously, it can be very hard to be denied it in a subsequent pregnancy. You should have this conversation with your healthcare provider and explain the reasons why you want to take it.  

Even though there is no evidence currently that it would help, there is also no evidence of harm, and it’s important that you are supported to do what feels right for you. 

Unfortunately, however, healthcare providers within the NHS are usually unable to prescribe medication that is outside guidance. If this is something you feel strongly about, you may wish to consult a doctor within the private sector. You should not try to buy progesterone without a prescription.

Progesterone treatment is only available on prescription. You should not use medication that has been prescribed for somebody else or share your medication with another person. 

Different types and doses of progesterone are used for different reasons, so it is important that you take the medication prescribed specifically for you.