It’s somewhat surprising that many people are reluctant to discuss miscarriage, given that it has such a devastating emotional impact on so many couples. A miscarriage is technically defined as the loss of a pregnancy prior to the 20th week of gestation. Beyond twenty weeks the loss of a pregnancy is called a stillbirth (or neonatal death if the baby is born alive). The vast majority of miscarriages occur in the first trimester of pregnancy, that is before 13 weeks (of course this means that once you have reached 13 weeks with a healthy pregnancy the chances of losing your baby are very low – less than one percent).
In the bad old days (very bad) we used to call miscarriages spontaneous abortions but the obvious negative connotations of that term led to a very appropriate change of name.
You might be surprised to hear how commonly miscarriages occur: up to two-thirds of all fertilised eggs will fail to progress into full-term pregnancies. However, the majority of these miscarriages go unnoticed because they happen very early on in the pregnancy, even before a period is missed. When we look at only those pregnancies that are recognised (i.e. those that cause a period to be missed), then around 15-20% will result in miscarriage. While, sadly, all women are at risk of miscarriage, it is a less common occurrence in young, healthy women than in older women and those with certain medical conditions.
As you might imagine, transforming two microscopic cells (a sperm and an egg) into a three or four kilo, eating, breathing, crying baby is an incredibly complex process. And when you consider that those cells need to copy their immense genetic code billions of times, it’s no surprise that the process can be less than perfect, and can make the pregnancy unable to continue normally. Not uncommonly, the embryo’s “spell-checking” mechanism falls short, and this can result in genetic abnormalities, such as having too many or too few chromosomes. In many cases, this means that the embryo or fetus would not be able to survive outside the womb, or would have a potentially significant disability (such as Down syndrome). Overall, around two-thirds of miscarriages occur because of some random genetic abnormality affecting the embryo. Because they happen randomly, you should be reassured that if this is the cause of the miscarriage, your chance of subsequently having a successful pregnancy is not affected by the miscarriage. In other words, having one miscarriage does not make you more likely to have another miscarriage (unless there’s some other medical reason for it – see below). It’s also worth noting that older women’s eggs are more likely to start off with chromosomal abnormalities, making miscarriage more common: around 25% of pregnancies will result in miscarriage for women aged 35-39, and about 40% for women over 40.
In addition, miscarriage can occur as a result of an infection acquired during the pregnancy, such as Listeria or toxoplasmosis, but these are very rare bacteria and when you see either your GP or me early on in your pregnancy, you’ll be given advice on how to avoid them. Finally, smoking and consuming large amounts of alcohol or caffeine have also been linked in some studies to an increased miscarriage rate, so ideally you should cut these out altogether (though a cup of coffee a day is perfectly safe).
Most importantly, you should realise that in the vast vast majority of cases, losing a baby is nobody’s fault. So if you are to experience a miscarriage, you should certainly not feel that anything you did was responsible for causing it, or that anything you could have done might have prevented it.
What are recurrent miscarriages, what causes them and how do we investigate and manage recurrent misscarriages?
In the James Bond book Goldfinger the bad guy (Goldfinger himself) tells James Bond – after running into James Bond a few times – that “once is happenstance, twice is coincidence and three times is enemy action.” He could have been speaking of miscarriages.
By definition the term “recurrent miscarriage” is applied to three or more miscarriages in one woman. Given how common miscarriages are it is easy for the statisticians amongst you to work out that three or more miscarriages in one woman may simply be due to chance (albeit distressingly bad luck), especially if she is over 35 years of age.
And while we investigate for the conditions listed below when a woman has had three (and sometimes two) miscarriage it is rare for us to find a “smoking gun” as a cause for recurrent miscarriages. This also means that even with three previous miscarriages a woman has a – relatively – high chance of a successful pregnancy the next time she conceives.
Apart from random genetic abnormalities, there are many other (but much less common) causes of miscarriage, many of which carry an increased risk of having a recurrent pregnancy loss. These include the following conditions affecting the mother:
- Polycystic ovarian syndrome (PCOS)
- Diabetes, especially when blood sugar levels are poorly controlled
- Rare genetic conditions affecting either parent – these are called inversions or translocations
- Thyroid disease
- Uncontrolled high blood pressure
- Autoimmune conditions, such as lupus (SLE) and antiphospholipid syndrome
- Rare blood clotting abnormalities, known as thrombophilias (such as factor V Leiden and protein C and S deficiencies)
- Abnormalities of the structure of the womb or birth canal, including fibroids; although these usually cause miscarriages later on in pregnancy (i.e. after 13 weeks)
Sometimes women are already aware that they suffer from one of these conditions before they become pregnant, while at other times they may unmask themselves only after they have caused a number of miscarriages. Depending upon a woman’s age and wishes, my usual policy is to start investigating for the conditions above after they have suffered three miscarriages (or two miscarriages for women over 35 years).
Most of the conditions listed above can be ruled out with blood tests and a high quality pelvic ultrasound scan.
If we find that one of these conditions is responsible for causing recurrent miscarriages, then we will treat you accordingly, and this may involve working together with another specialist doctor with experience treating the particular condition involved. For example, women with diabetes will require especially tight control of their blood sugar levels; women with thrombophilias can be treated with a low-dose daily tablet of aspirin or blood thinning injections; women with PCOS can be treated with a drug called metformin and women with structural abnormalities of the uterus causing miscarriage may sometimes require surgery. These treatments aim to increase your chances of carrying a successful full-term pregnancy.
Miscarriage symptoms include vaginal bleeding and pain in the lower abdomen – often cramps just like those you experience when you get your period – but worse. There may also be back or buttock pain. Significant or severe abdominal pain in early pregnancy – especially with little or no bleeding is a symptom of an ectopic or tubal pregnancy. An ectopic pregnancy is a medical emergency. If you experience these symptoms early in your pregnancy and your pregnancy has not yet been demonstrated to be inside your uterus by ultrasound you must attend your local emergency department immediately and by ambulance if necessary.
Of course almost all women experience a mild degree of abdominal cramping during early pregnancy – this is almost certainly due to the stretching and growing of the uterus. In the absence of vaginal bleeding this discomfort is almost certainly normal. However we would be happy to assess you any time if you are concerned about abdominal discomfort in pregnancy.
About one woman in every four experiences some degree of bleeding in the first trimester, and less than half of these women will suffer a miscarriage. However, any bleeding at all needs to be taken seriously, no matter how light or painless, so if this occurs, please contact your GP or Miscarriage Care so we can organise an ultrasound and a blood test to check on your pregnancy. If the bleeding is very heavy (such that you are changing your pads more frequently than hourly with or without passing blood clots) or you have severe pain or a fever, you should attend your nearest hospital emergency department immediately and by ambulance if necessary.
A crucial part of our investigation of bleeding in early pregnancy is a high quality ultrasound scan. If – in the presence of bleeding – an ultrasound demonstrates that your baby has a normal heartbeat present then you have a 95 percent chance that you will not miscarry.
f course women have been miscarrying for centuries without gynaecologists seeing them or operating on them so the process can be considered to be normal and – in many cases no intervention is necessary. Unfortunately through the centuries a proportion of women miscarrying spontaneously suffered significant blood loss and / or infections that had very serious consequences.
The type of treatment required depends upon the situation and there are a number of possibilities:
This is when some bleeding has occurred but we have demonstrated that the baby is viable (i.e. we have seen its heartbeat). No treatment is required other than ongoing careful observation and a follow up ultrasound to check that the baby is continuing to develop normally.
In this instance bleeding has occurred and the pregnancy has already been passed. In this instance ultrasound demonstrates that the uterus is empty. No treatment is necessary and we would expect the bleeding to resolve over the next week or so.
This is where a woman often suffers quite heavy bleeding and cramping and we find on examination that the cervix (or neck of the womb) is partly open. Ultrasound usually demonstrates that there is some pregnancy tissue still within the uterus. We can manage this situation conservatively (i.e. by “waiting and seeing” if the miscarriage will become complete) but we usually have to perform a surgical evacuation of the uterus (also known as a Dilatation and Curettage, or “D and C”) in order to empty the uterus and stop the bleeding.
This is the majority of miscarriages in this day and age. A missed miscarriage is when a woman either has an ultrasound because of a small amount of bleeding OR a routine ultrasound (a dating scan, for example) and that ultrasound shows that her baby has died or failed to develop at all (a so called “blighted ovum”). In this instance there are three options:
- Conservative management – i.e. waiting and seeing if the woman will spontaneously miscarry completely,
- Medical management – this is where we give drugs usually used in terminations of pregnancies in order to induce a – hopefully complete – miscarriage, or
- Perform a surgical evacuation of the uterus.
When deciding between the three major treatment options outlined above (conservative management, medical management and surgical evacuation) it is worth remembering that each option has its pros and cons.
The main benefit of conservative management is that you will avoid having to have an operation, but this option is not suitable for women who have had heavy bleeding, which could become dangerous if we were to let it continue unchecked. The main disadvantage of conservative management is that in some cases the miscarriage does not complete naturally such that there are “retained products of conception” (usually some placental tissue) within the uterus. This can then cause infection or further bleeding for several days, which may subsequently require a surgical evacuation anyway. For some women – particularly those whom have lost their babies very early on in pregnancy (i.e. before six or so weeks), allowing a miscarriage to occur naturally will be no worse than a heavy period, while for others (especially those a bit further on in their pregnancies) it will be a more distressing experience with quite significant cramping and bleeding.
Medical management involves giving a woman drugs in order to induce a miscarriage when her baby has been demonstrated to be “non viable” but the actual miscarriage process has not yet begun to occur (remembering that spontaneous miscarriage may be some weeks away). The drugs used for this process include RU 486 (the “abortion pill”), misoprostol or cervagem. These drugs can be given either as tablets by mouth or into the vagina as pessaries. The advantages and disadvantages of medical management are as per conservative management. The main advantage is avoiding surgery and the main disadvantages are that the process can be prolonged, unpleasant and – not infrequently – can require surgery anyway. To be truthful we are not big fans of this approach but would be willing to organise it if a woman specifically requested medical management of her miscarriage.
Globally surgical evacuation of the uterus (or “D and C”) must be one of the most common operations performed (this being due to how common miscarriages are plus the fact that this is how the vast majority of terminations of pregnancy are conducted). It is also one of the most straightforward and safe operations around although – as with all medical procedures – complications can occur.
The process for an evacuation of the uterus involves being admitted to hospital for a short day stay. You will need to have nothing to eat or drink for six hours prior to the operation. Under some circumstances (such as if you have not had a baby before, you have had no bleeding and your cervix is closed) we sometimes insert a pessary into your vagina a few hours before the operation. This pessary softens the cervix and makes dilating (opening) the cervix safer than not using it. When you go to the operating room the anaesthetist will put a drip in your arm and then you will be given a light general anaesthetic. The operation itself will take about fifteen minutes.
While you are asleep we gently open (or dilate) your cervix until it is about 8 millimetres open. Sometimes – particularly with incomplete miscarriages – the cervix is already open so we can omit this step. We then use a thing like a drinking straw attached to a small suction machine to suck out the contents of the uterus. All of this is done under careful ultrasound guidance in order to prevent injuries and to try and prevent us leaving any tissue behind. We send the material from your uterus to the laboratory for analysis including checking for chromosomal abnormalities.
You will wake up from the anaesthetic in the theatre recovery room and then you will stay in hospital for a couple of hours after your operation. Your partner or a friend will need to take you home from the hospital and I would advise staying home the day after your surgery. You will have bleeding like a period (at worst) for one to two weeks after the operation. Your next normal period should occur a month or so after your operation.
There is no reason why you should not try to conceive again as soon as your bleeding has resolved.
While Evacuation of the Uterus is a very safe operation and it is almost always completely effective it is important to remember that – as with any procedure – complications may occur.
These complications include:
- Anaesthetic Complications. In this day and age anaesthetics are incredibly safe although the risk of suffering some sort of major complication from your anaesthetic is approximately 1:100,000. This is less than your chance of being severely injured in a car crash on your way home from the hospital. Remember that if we are managing your miscarriage your anaesthetic will be administered by an anaesthetic specialist, not a doctor in training.
- Retained placental tissue. With the best care in the world (including using ultrasound) we sometimes leave a small amount of placental tissue inside your uterus. This may pass out spontaneously but if it does not you may experience abnormal bleeding, infection within the uterus or undue discomfort. If any of these symptoms occur you must contact us immediately. A few women (less than five percent) of women who have an evacuation will need to have the operation repeated in order to remove retained placental tissue.
- Excessive bleeding. Excessive bleeding is very rare at surgical evacuations of the uterus for first trimester miscarriages (indeed the operation usually arrests the bleeding that has been caused by the miscarriage). However we make sure there is a sample of your blood in our Blood Bank just in case a blood transfusion is required, as is the case in fewer than one percent of Surgical Evacuations.
- Damage to the cervix or uterus. In a small number of cases the cervix or uterus can be injured by the instruments used to perform a Surgical Evacuation. These injuries are rare and even if they occur they only extremely rarely cause ongoing problems. However the occurrence of such injuries is why we perform our Evacuations under ultrasound guidance in order to minimise the likelihood of such injuries.
- Overdoing it. Sometimes doctors can “overdo” an Evacuation, particularly if they use an instrument called a curette. A curette is a metal object with a long handle that is a bit like a soda spoon (if you know what I mean, and sticking with the Milk Bar metaphors). Sometimes doctors – and I think this is a little more likely with junior doctors who are anxious not to leave any tissue behind – “over scrape” the lining of the uterus such that its inner layer is removed. This can cause cessation of your periods because the front and back wall of your uterus stick together. This problem is called Asherman’s Syndrome. While Asherman’s Syndrome is rare it can cause ongoing reproductive problems and requires complex surgery to correct it. We believe that performing you Evacuation under ultrasound prevents us “overdoing” the operation because we stop as soon as we see that the uterus is empty. In addition we do not use the hard metal curette, sticking with the more soft suction device instead.
We are often asked when couples can start to try for another pregnancy after suffering a miscarriage. In the old days we used to tell people to wait three months after a miscarriage before trying again.
The reasons for this advice were:
- Before ultrasound was widely used to “date” pregnancies we relied on the occurrence of regular periods to assist us in estimating when babies were due to be born, and
- We thought three months was an appropriate time interval for the grieving process to take place (remembering that the grief of a miscarriage is never truly completely over.
Notwithstanding the importance of grieving after a miscarriage these reasons are really bollocks. Most people who suffer miscarriages these days are not getting any younger and it is natural to simply try again as soon as possible. Accordingly I suggest that you begin to try again for another baby as soon as the bleeding following your miscarriage has resolved.
Particularly if your recent pregnancy was unplanned you should take a moment to make sure that your health is optimal for a pregnancy before embarking upon one. Just run through this check list before getting started:
- Do you need any vaccinations, in particular to Rubella?<
- Have you had a normal PAP smear within the last 12 months? If not then this is an ideal time to have one.
- Are you taking an appropriate vitamin supplement that contains both folic acid AND iodine (Blackmores Pregnancy and Breastfeeding Gold is one such example)?
- Are you eating a healthy low(ish) carb / low(ish) fat diet?
- Have you stopped smoking?
- Are you being sensible with alcohol and caffeine (not too sensible – life is short, after all)?
- Are you aware of the need to avoid foods that might contain Listeria (soft cheeses, deli meats etc) once you are pregnant?
- Do you have any medical conditions like high blood pressure or diabetes that could be optimised prior to falling pregnant?
It is normal to be anxious about your baby’s welfare when you fall pregnant after a miscarriage – don’t let anyone tell you are being paranoid because, as Woody Allen put it, “You’d be paranoid too if the whole world was out to get you!”
Contact my office (or that of your favourite obstetrician) as soon as you are pregnant and we will organise an early dating ultrasound scan and we will make sure we keep a close eye on your baby through the first trimester.
Both physically and emotionally, a miscarriage can be an extremely difficult experience to deal with, no matter how early on in the pregnancy it occurs, and many people will not seem to understand your grief. In addition to offering you our own support, and guiding you through the management of miscarriage, we are happy to arrange professional counselling for you and your partner, should you feel that this would be of benefit.
Someone once said, “If you think miscarriage is a lonely experience, join the crowd.”
Dr Alex Owen, a former Medical Student of Dr Buist, kindly drafted this informational material and wrote the vast majority of the text, including the Goldfinger reference. Dr Buist has edited the document and takes full responsibility (as Kevin Rudd might say) for any errors within the document.