Idiopathic scoliosis is fairly common in young girls, many of whom plan to have children at some point in their lives. The effects of scoliosis on the back, the pelvis, and in some cases the respiratory system, frequently prompt the question from
a prospective parent: “What are the risks of pregnancy?”
The short answer is that in most cases there will be few if any problems, but those mothers-to-be who have the disorder understandably have a lot of questions about the effect their scoliosis can have on them and their child. These concerns can be about the health risks of pregnancy to a mother with scoliosis and whether there will be any obstetric problems during the pregnancy or birth. Many prospective mothers are anxious that they could pass scoliosis on to their children, and whether the condition could pose a risk to carrying the child to term or cause difficulties in delivery. And, naturally, parents also worry about the effect that becoming pregnant could have on their body in general and curve in particular.
The commonest type of scoliosis is the idiopathic form, which becomes apparent during the adolescent growth spurt at around the age of 10–14 years. By this stage the development of the lungs and heart is complete, and apart from a mild degree of restricted lung capacity, individuals with adolescent-onset scoliosis rarely encounter breathing problems during pregnancy or as they get older.
In some people who are born with scoliosis (congenital type), or in whom the scoliosis is associated with a neuromuscular condition, such as muscular dystrophy or poliomyelitis, lung size may be more severely restricted because the lungs haven’t had room to grow. Breathing will also be affected if the muscles that expand the rib cage are weak.
A useful way to assess lung size is to measure vital capacity with a simple blowing test — this measures the total amount of air that can be actively expelled from the lungs after taking in maximum breath. If the vital capacity is less than 50% of what is predicted, a full review by a respiratory specialist is advisable.
However, evidence suggests that as long as the vital capacity exceeds about 1 litre the outcome will probably be good. Indeed, recent successful pregnancies have been achieved in individuals with a vital capacity of about 600 millilitres (0.6 litre), provided that they received respiratory support. Below this lung size problems with a reduction in oxygen level (hypoxaemia) can occur. Low oxygen levels characteristically worsen on exertion and during sleep, and may be accompanied by a rise in the concentration of waste gas (carbon dioxide).
A low oxygen level is harmful to the growing baby and can also lead to heart strain in the mother. Fortunately this situation is rare, and monitoring of oxygen levels can be easily done during exercise and at night. In very few cases with severe scoliosis, respiratory support at night can be provided by a small breathing machine. This is called non-invasive ventilation. Non-invasive ventilation is needed only in a few patients – usually those with a vital capacity of less than 1 litre and/ or weak muscles. Provided that this breathing support is used and carefully monitored, successful outcomes for mother and baby can be achieved.
Sometimes an early-onset scoliosis will be associated with a congenital heart defect (eg, hole in the heart). Heart problems will nearly always be detected in childhood and corrected where necessary. However, to ensure that there are no heart problems, an ECG (electrocardiograph) and echocardiogram (an ultrasound scan) of the heart can be done.
Provided that the oxygen level of the mother is fine and heart function is good there should be no threat to the growth of the baby, and the enlarging uterus easily adapts to the shape of the mother. Idiopathic scoliosis is probably inherited on multiple genes. Although idiopathic scoliosis sometimes runs in families, this is not common, so parents can be reasonably reassured that the risk of the baby developing scoliosis is low.
It is important to remember that most people with adolescent onset scoliosis will not have a low vital capacity or heart problems. Simple breathing tests can check on lung function and if there is any query about this your GP can refer you to a respiratory specialist.
There are exciting new developments in genetics, but it is not yet possible to provide a screening test for scoliosis. Ultrasound scans of the baby will of course check overall growth, including spinal development. The exception to this are some of the congenital forms of scoliosis, which are associated with conditions such as neurofibromatosis, and with some types of myopathy and muscular dystrophy. These do run from generation to generation, and some conditions can be detected prenatally. Genetic counselling services exist in all regions of the UK and any individual with concerns can be referred for advice by their GP or hospital specialist.
Large hormonal changes occur during pregnancy with an increase in oestrogen, progesterone, and relaxing. These hormones help to loosen the ligaments of the pelvis and lower spine to ease the birth of the baby. Although concerns have been raised that hormonal fluctuations could lead to progression of a spinal curvature, most studies are reassuring on this point, suggesting that changes in the degree of scoliosis are slight, provided that the curvature is stable at the outset of pregnancy.
Some degree of breathlessness is common from the early months of pregnancy in all women. This shortness of breath is partly caused by the rise in progesterone, which stimulates breathing by increasing the depth of each breath. Blood volume also increases. These normal physiological changes are well tolerated and only likely to prove a problem if the vital capacity is low or heart function is compromised.
Around 80% of people will have some sort of back pain in their life so it is no surprise that many pregnant women experience discomfort as a result of the strain put on their back. As the baby grows, the additional burden affects the mother’s posture and the abdominal muscles work hard to maintain neutral posture. The abdominal muscles stretch as the baby grows, lessening their effectiveness in maintaining neutral, usual, posture, and consequently additional strain is placed on the muscles that run parallel to the spine. As with scoliosis outside pregnancy—and back health in general— keeping the core strong and maintaining a reasonable level of fitness will help to alleviate back pain in pregnancy.
In some women with more severe scoliosis early / preterm delivery (less than 37 weeks gestation) is necessary because the effect of the growing baby and uterus on the mother’s breathing means that the woman becomes uncomfortably short of breath even with the help of non-invasive ventilation. Also, in some women the baby does not lie head down but transverse (across the abdomen) making a Caesarean birth necessary
It is always sensible to discuss the management of labour in advance with the midwife, GP, obstetrician, and anaesthetist.
Comfortable positioning—the position adopted during labour and delivery is crucial for the comfort of the spine, and long immobilisation is unhelpful. The most comfortable position (a relative term!) will, of course, vary between individuals.
Epidural pain relief may be able to be used during labour. However, epidural insertion can be challenging, particularly in women with severe scoliosis or in those who have had corrective surgery with metal rods and fusion. In these individuals, it may be more difficult to locate the right place for the regional / spinal / epidural anaesthetic or produce an even spread of this agent. Indeed, in some patients, epidural insertion might not be possible and other options for pain relief during labour should be considered. It is therefore important to have an early assessment and discussion with your obstetric anaesthetist to enable pain relief for labour to be individualised. Some women might require a caesarean section, and again it is vital to have an early discussion with your obstetric anaesthetist about the most appropriate type of anaesthetic.
The good news is that it has been known for many years that the outcome of pregnancy in scoliosis is generally good. A survey, carried out by Dr Phillip Zorab and Dr David Siegler, of 118 pregnancies in 64 women with scoliosis found that no serious medical problems were encountered. 17% of mothers reported increased breathlessness and 21% had increased back pain but found it tolerable. A normal delivery was achieved in most women with only 17% requiring a caesarean section for obstetric reasons.
More recently in a study of 142 pregnancies in women who had been treated with corrective scoliosis surgery there was a slightly higher proportion who had a caesarean section compared with the general population, but the rates of complications in pregnancy and delivery were no higher than in the general population and the offspring were healthy. About 40% of mothers developed low back pain during pregnancy but this had resolved by 3 months after delivery in most. A survey of cases of mostly idiopathic scoliosis in India published in 2010 again shows a higher caesarean rate than in individuals without a scoliosis but there were no major problems with the mothers’ health.
These results justify an optimistic outlook in the main. However, individuals with congenital or early-onset scoliosis, and those with muscle weakness, breathlessness before pregnancy, or heart problems, should always seek medical advice.
In recent years at the Royal Brompton Hospital, several mothers with quite severe scoliosis have been supported throughout pregnancy with good results, and only a few have been advised to avoid pregnancy. Pre-pregnancy counselling is an excellent idea for all people contemplating pregnancy and is especially relevant to those with scoliosis. It is for this reason that the Royal Brompton/ Queen Charlotte’s/ Hammersmith/ St Thomas’ Hospitals in London run a prepregnancy counselling service. Here, the individual relevance of the above considerations can be discussed in detail, and advice given about sensible health measures, vitamin and folate supplementation, posture, and exercise. In addition, the management of any coexisting problems such as asthma, hayfever, indigestion, or diabetes can be optimised, in order to give both mother and baby the best chance.
For more information on local pregnancy counselling services speak to your GP.
At any point if you feel unsure or have questions, please contact SAUK and one of the friendly Helpline staff will help to alleviate any concerns or fears that you may have. SAUK also has a fantastic network of members and volunteers who are happy to talk to you about their experiences of pregnancy with their scoliosis. SAUK exists to ensure that you should never feel alone during your scoliosis journey.
Personal account of pregnancy after fusion
At the time I was diagnosed with idiopathic scoliosis in 1995, when I was 14, and when I underwent subsequent corrective surgery in July, 1997, aged 16, the question of pregnancy and birth was not top of my list of considerations. In fact, I don’t think it was anywhere on my list!!
Fast forward 8 years and my husband and I decided to try for a baby. I contacted my surgeon to ask if there was anything I should be taking into consideration or anything I should be aware of so that I was fully prepared. He advised that there was absolutely no reason why I should not be able to experience a perfectly normal pregnancy and birth. This gave me the confidence to embark on this new chapter.
My husband and I welcomed Max into the world (bang on due date!) in June ,2008, and he was followed by Sam in March, 2011. Both pregnancies were very straightforward. I experienced no significant back pain or discomfort. I carried both comfortably and continued to be very mobile throughout. I was looked after via ‘shared care’ which meant I had the usual appointments with the community midwife, but I also was overseen by a consultant. This was as much because of my fusion as it was my previous two miscarriages (before Max’s arrival).
During both pregnancies, an appointment was scheduled with an anaesthetist because of my surgical history. This was a very useful discussion. She advised, both times (I was obviously a little more clued up the second time!) that they would not be able to administer an epidural for two reasons: 1) the fusion meant that I would not be able to bend and separate the vertebrae for them to site the needle, 2) the scar tissue would make it difficult for them to locate the right place to administer the drug. In the event of needing a caesarean, I would have to have a general anaesthetic. She did mention that there would be the possibility of giving a slightly stronger painkiller than normal to bridge the gap if needed.
Armed with this knowledge I was perfectly happy that I knew the hospital would be fully up to date and that I knew what I could and couldn’t have. I did still make sure I wrote in capital letters all over my notes ‘CAN’T HAVE AN EPIDURAL’!!!!
Both of my boys laboured well without any complications, and I had both boys naturally without any pain relief. With Max, I did experience some continuous lower back pain for which they recommended the pool – it was a game-changer and definitely something I would recommend! The midwife was very attentive, checking with me frequently how the pain was. Sam arrived too quickly for them to even finish filling the bath!
It’s worth casting your mind a little further forward to post-pregnancy too. I knew our three door sporty number wasn’t going to cut it when I was trying to put a baby in a rear-facing car-seat in the back. I can’t twist! So we ended up changing our car to a five door so that it was easier to get a baby in and out. The weight of your pram, ease of putting up, taking down and handle height were all factors we assessed when buying. It sounds pedantic but when you think how much time you’re going to be spending doing it, it really will make a difference, I promise!
There is not a lot of discussion around pregnancy and scoliosis, so as with all of my scoliosis experience, I always aim to be open and honest, in the hope that it helps make someone else’s journey that little bit lighter. SAUK provides invaluable support during these times. I wish I had known about them sooner.