Most of the women I care for worry about miscarriage, particularly in the early months of pregnancy. Sadly, miscarriage is common in the first twelve weeks. Whenever it happens, it can be a distressing experience. However, it's important to remember that you are still much more likely to have a healthy, uncomplicated pregnancy.
Miscarriage facts and figures
A miscarriage is the loss of a pregnancy in the first 23 weeks. It's tricky to know exactly how many miscarriages take place. The truth is that frequently a miscarriage can happen before the mum even realises she is pregnant. The estimated figure is that miscarriage happens in up to one in four recognised pregnancies, with the great majority happening in the first trimester before 12 weeks. A late miscarriage is fortunately much less common, so there is good reason to relax a little after 12 weeks. After 24 weeks, the delivery of a baby who has died in the womb is no longer described as a miscarriage but is referred to as a stillbirth.
Facts and figures can't express the pain and the individual stories behind the losses. However, many couples tell me they want to know the statistics to help them understand their loss and start to look forward to the future:
- 20% of women go to hospital with bleeding in the first twenty weeks of pregnancy
- Miscarriage occurs in around 10–25% of pregnancies, although some may occur in the first five weeks, often before a woman knows she is pregnant - known as a 'chemical pregnancy'
- 85% of miscarriages happen in the first twelve weeks
- In the UK, 50,000 women are admitted with early pregnancy problems every year
- After a normal scan, 95% of those with bleeding will go on to have an uncomplicated pregnancy
- Over half of women with bleeding before 20 weeks will continue their pregnancy
Miscarriage risk
Some women do have a slightly higher risk of having a miscarriage. This includes those with underlying health problems and older mothers. Women who make potentially harmful lifestyle choices (such as heavy drinking of alcohol or caffeine, smoking and taking recreational drugs) can also be more likely to suffer pregnancy loss.
Although you cannot have any impact on chromosomal conditions or your age, there are some things you can do to bring down your overall risk of having a miscarriage. By getting to a healthy BMI, eating a balanced diet, kicking any bad habits and cutting down to 200mg of caffeine a day, you may help increase your chances of continuing your pregnancy and giving birth to a strong and healthy baby.
Early miscarriage
More than 85% of miscarriages happen in the first 12 weeks of pregnancy. These are known as 'early miscarriages'.
Causes of early miscarriage
It is thought that many pregnancies may be lost early, in the first five weeks, often before a mum knows she's expecting. The cause of many early miscarriages is not fully understood. However, it is believed that most are caused by chromosomal problems in the developing baby. Later, problems with the placenta can also lead to pregnancy loss.
Chromosomal abnormalities
It can help to think of the chromosomes as the building blocks of our genes. They contain the blueprint for developing every single cell in the body, with fifty per cent coming from the egg and fifty per cent from the sperm. If there's a serious problem when they combine at the time of conception, or during early development, this can mean that the baby is unable to live and there can be an early loss of the fetus.
Around half of early miscarriages may be caused by these kinds of genetic problems. But before you start to worry, it's important to understand that this usually doesn't mean you or your partner are carrying a chromosomal problem. It's often a new abnormality in the baby and most couples go on to have a healthy baby in the future.
Problems with the placenta
The placenta is your baby's life-support machine. It links your blood to your baby and is the source of food, fluid and oxygen. If there is a problem with the development or function of the placenta, it can cause miscarriage.
"I have been pregnant twice. The first time I had a miscarriage around six weeks. I was considered high risk. I had a pulmonary embolism when I was twenty-five. The cause was the pill. Therefore, my specialist team decided to put me on blood thinners during my pregnancy, which I had to inject in my stomach. I was scared that the blood thinners would harm the baby. When I found out I was pregnant two months after the miscarriage I went to my specialist immediately and my pregnancy was fantastic. My daughter is nine now and healthy."— Patty, London
Dr Keith Duncan says:
Pulmonary embolisms are blood clots that reach the lungs and block blood flow, resulting in a heart attack or other serious medical problem. Some birth control pills are known to cause these blood clots. In addition, women who have had miscarriages are often given blood tests to check for genetic problems that may lead to blood clots. These inherited clotting problems affect about one in ten people. The fear is that having one of these clotting problems may cause clots to form in the placenta, choking the delivery of oxygen and nutrients to a growing baby. Research in the past suggested having a clotting disorder can lead to sticky blood and the risk of miscarriage, so doctors may prescribe a blood thinner to help prevent pregnancy loss and growth problems in the baby.
What will happen?
If you have had an early miscarriage, you may notice some bleeding or suffer lower abdominal pain and cramping. Sadly, you may notice no symptoms, and discover your loss on a routine ultrasound scan. This is known as a missed miscarriage.
With time, a full miscarriage will usually happen naturally. However, this can take days or sometimes weeks. Some women prefer if this process is speeded up, so they can put this difficult and stressful experience behind them and start to recover physically and emotionally. This can be done by the use of medical treatment or by a small operation.
Will it happen again?
"I felt anxious throughout the pregnancy due to the previous miscarriage. I kept thinking this pregnancy would end in miscarriage also. Compared with the first pregnancy, when I assumed everything would go perfectly, from the minute I found out I was pregnant, I did not allow myself to think ahead or get excited in case things didn't go well."
— Pauline, London
The good news is that whilst miscarriage is common, recurrent miscarriage is not. Only two per cent of pregnant women experience two pregnancy losses in a row, and only about one per cent have three consecutive pregnancy losses.
The technical definition for recurrent miscarriages or 'recurrent pregnancy loss' (RPL) requires three or more consecutive losses of recognised pregnancies before Week 20, or the fifth month of pregnancy. Currently, it isn't clear whether early pregnancy losses diagnosed by sensitive pregnancy tests and not by ultrasound should be included in this definition. Most doctors believe it is reasonable to send tests and start treatment of RPL after two consecutive miscarriages.
The risk of recurrence depends on many factors, including the cause of the first miscarriage, the age of the mother, and any previous history of a live birth. However, it's important to remember that most women with RPL have a good chance of eventually having a successful pregnancy, whether or not a cause is discovered and treatment initiated.
Looking forward
Your body is designed to recover physically from the demands of a miscarriage. However, when a baby dies it can be difficult to cope with your emotions and adapt to the loss of the baby you planned and the future you'd imagined.
If the worst does happen and you lose your baby, it can be a lonely and frightening experience. You may have avoided telling people about your pregnancy, which can add to your sense of isolation. Please understand that you are not alone. Even if a problem shared isn't exactly halved, it can help to talk to others about your feelings and your fears. Talk to your healthcare team and share your emotions with your partner, your family or trusted friends.
Mid-trimester loss
Most miscarriages happen in the first trimester. However, as many as fifteen per cent of miscarriages occur later (between 15 and 24 weeks), so they are not as rare as people think. In my unit, every month we see a patient who is suffering a late loss - it's one of the most upsetting and challenging parts of my job.
The sad truth is that we often don't fully understand the reason for late miscarriage, but there are a number of causes and conditions that could potentially increase the risk. The good news is that with early diagnosis of these, we can make a difference and prevent problems occurring.
Causes of late miscarriage
- Cervical insufficiency: Problems with the neck of the womb can make it more likely to open up earlier in pregnancy. This weakness can be caused by surgery to the cervix, including treatment for abnormal or precancerous cells. It can also be due to birth trauma, or there may be an in-built tendency. If your healthcare team are aware of the risk, they can start treatment to prevent the cervix dilating too soon. An ultrasound scan can be done to assess the length of the cervix. If changes are noticed soon enough, there is research evidence that hormone therapy with progesterone pessaries can significantly decrease the risk of miscarriage. Also, a special stitch can be placed around the cervix earlier in pregnancy (known as cervical cerclage) to prevent premature dilatation.
- Infection: Infections can really take their toll on your body, and that's especially true in pregnancy. Any severe infection such as a UTI spreading to the kidneys, septicaemia or bad gastroenteritis (especially bacterial infections) can increase the risk of pregnancy loss. Pelvic and vaginal infections can be a particular problem. If they spread to the womb, they can make the membranes inflamed, a condition known as chorioamnionitis, which can kick off contractions and miscarriage. Although this is thankfully rare, it's essential to get medical help promptly if you are feverish and unwell or have an unpleasant or smelly discharge.
- Illness: When you have a chronic health condition, you become used to carefully managing your own health. This is particularly vital when you're expecting because chronic health conditions like diabetes, thyroid problems, high blood-pressure and kidney disease can increase the risk of miscarriage. It can really help if you get expert medical assessment and support early in pregnancy, or ideally when you are trying to conceive. This can ensure you're in tip-top health so your body is in the best condition to build a healthy baby.
- Medication and treatment: It's important to be vigilant and get expert advice before taking any medications when you're pregnant. A number of drugs, herbal remedies and essential oils may trigger pregnancy loss. Check with your doctor, midwife, pharmacist or therapist before taking anything - that includes 'natural' and common over-the-counter treatments.
- Problems with the womb: Sometimes the shape of the womb can affect the attachment of the placenta or the healthy growth of the baby. This is uncommon, but can be caused by problems during development or by the growth of fibroids. If this has caused a miscarriage for you in the past, it may be worth consulting a gynaecologist to consider whether surgery could make a difference, before planning any further pregnancies.
- Twin and multiple pregnancies: The extra size and weight of multiple pregnancies can put extra pressure on the cervix, and trigger early changes to the neck of the womb and the danger of labour starting too soon. This increases the risk of premature deliveries and mid-trimester loss.
- Genetic problems and fetal abnormalities: Some late miscarriages are caused by a problem with the chromosomes in the baby or developmental abnormalities that are incompatible with life. Although it is not a consolation for the loss, it can be reassuring to know that most women go on to have successful pregnancies in the future. However, it is worth further investigation and genetic counselling if there is a strong family history of pregnancy loss.
Understanding and planning for the future
After a late miscarriage, you may be offered tests to help understand what has caused your loss. This can include a post-mortem examination or autopsy, which I understand is difficult to consider when you're still reeling from your loss. However, these investigations can help you discover why you lost your baby and whether preventative treatment will be able to help prevent any problems in future pregnancies.
If you have experienced recurrent pregnancy loss or a late miscarriage, Dr Duncan can support you with specialist consultations, targeted screening and a personalised care plan. Contact us today to book your appointment with Dr Duncan.
Frequently Asked Questions
The risk of miscarriage is highest in the first 12 weeks of pregnancy, with around 85% of all miscarriages occurring during this period. After 12 weeks, the risk decreases significantly, and there is good reason to feel more reassured once you pass this point. After 24 weeks, pregnancy loss is classified as a stillbirth rather than a miscarriage.
Yes, some lifestyle factors can increase the risk. Heavy alcohol consumption, smoking, recreational drug use and excessive caffeine intake (above 200mg per day) have all been associated with a higher risk of pregnancy loss. Reaching a healthy BMI and eating a balanced diet before and during pregnancy can help reduce overall risk. That said, the majority of miscarriages are caused by chromosomal problems in the developing baby and are not within your control.
A missed miscarriage is when the pregnancy has been lost but the body has not yet recognised this, meaning there may be no bleeding or cramping. It is often discovered during a routine ultrasound scan.
Recurrent pregnancy loss (RPL) is technically defined as three or more consecutive losses before Week 20. However, most doctors consider it reasonable to begin investigation and treatment after two consecutive miscarriages. Only around 2% of women experience two losses in a row, and only around 1% experience three or more. If you are concerned, speaking to a specialist sooner rather than later is always worthwhile.
For most women, yes. Physically, many healthcare professionals advise waiting until after your first period following a miscarriage, both for dating purposes and to allow time for emotional recovery. The majority of women who have experienced a miscarriage - even a recurrent one - go on to have successful pregnancies.
You should consider seeking specialist advice if you have experienced two or more miscarriages, if you have had a late miscarriage, if you have an underlying health condition such as diabetes or a clotting disorder, or if you simply want reassurance and a clearer picture of your individual risk. Early, expert assessment can make a real difference - both to your physical outcomes and to your peace of mind.
This post is adapted from Dr Duncan's new book, Anything Pregnancy. If you've enjoyed reading it, the full book is available to purchase on Amazon.