IRRITABLE UTERUS

Written by Caroline Meyer

We notice many of the outward changes when we are pregnant but seldom stop to think what is happening internally. The uterus goes through many changes during the pregnancy and while this is mostly completely normal and expected, sometimes it behaves a bit differently. The uterus expands as the baby grows and from the second trimester you may also start noticing Braxton Hicks contractions. These contractions are mild and irregular and will stop after a while. Usually hydrating and rest will make them fade quite quickly. 

For some women, this can also be rather different. The uterus does not contract in an expected way and these unusual contractions may be what is referred to as an irritable uterus. During pregnancy the muscles inside the cervix keep it closed. When you go into labour, the outer muscles contract. This causes the cervix to open and allows you to push the baby out. Labour is usually regular contractions that are quite urgent and strong. An irritable uterus does not result in strong contractions but feels more like a twitch. It does not result in labour and does not cause the cervix to dilate at all. The cause of these internal twitches is not fully understood at this time but does seem to be related to orgasm, dehydration, constipation, stress, exercise, heavy lifting and even a full bladder in some people. While these is not much research done at this point, there does seem to be a link between irritable uterus and preterm labour. The risk was close to 8% higher in women with irritable uterus symptoms that those without. Further research is needed to confirm the previous study. 

Irritable uterus differs from Braxton hicks in that the contractions happen far more regularly and can be painful and can last a lot longer. They also tend to be a lot more regular and the contractions are more frequent. These contractions can actually be severe enough to be mistaken for actual labour. Irritable uterus contractions may also include pain or pressure in the back, leading women to think they have started true labour. Braxton Hicks usually subside fairly quickly while those caused by an irritable uterus can continue for some time and worsen with movement such as walking. It can cause the belly to feel very tight and can remain in this state for more than an hour. 

If you are experiencing contractions before 37 weeks it is important to consult your doctor, even if you believe it to be irritable uterus symptoms. They will do a check up and run a few tests to determine if it is labour or irritable uterus. A belt will be placed around the belly to check the length, strength and duration of any contractions that may occur. An ultrasound may be done to check on the cervix length (it starts to shorten before true labour). There may also be an analysis of the vaginal secretions. While this is not always accurate, finding foetal fibronectin in the secretions may mean preterm labour. 

There is no actual treatment for irritable uterus at this point and it can result in sleep disturbances and added fatigue. To reduce the chance of contractions happening due to this syndrome, stay hydrated, empty your bladded often, avoid lifting anything heavy, try and reduce your stress and get enough sleep. You can also try eating small, regular meals and avoid caffeine. Lying on your left side has also given some relief to women with the malady.  Check with your caregiver if you can use a magnesium supplement, which can also provide some relief. If nothing seems to work, your doctor may prescribe medication that can reduce the strength of the contraction or potentially prevent it from happening. 

If your risk of delivering preterm seems high your doctor may recommend partial or complete bed rest. This means you could spend an extra 4 hours to all your time in bed besides bathroom breaks and check-ups. No sexual activity would be allowed at all. This may help stop preterm labour for longer, giving your baby more time to develop before coming into the world. 

Unfortunately, the amount of information on irritable uterus is minimal and it can be quite disturbing, especially for first time mums. If you have any concerns you should consult your doctor or midwife. If you experience any leaking or bleeding, pressure in the pelvis, reduced foetal movement or more than 5 contractions an hour or very painful contractions, seek advice from your care giver immediately. If you have concerns at any point in your pregnancy, speak to your midwife or doctor, especially if you have other risk factors for preterm labour as well.