Premature Labour

According to the World Health Organization (WHO), each year an estimated 15 million babies are born prematurely. While medical advances have greatly improved over the years, premature birth is the most common cause of death among babies in the world. This article will explain the signs, symptoms and management, which you will find useful, should you go into premature labour.

Firstly, here’s an explanation on what’s considered to be a premature baby.

What Is Considered To Be A Premature Baby?

What is defined as full term birth can vary by up to five weeks (week 37 to week 42); a baby born prior to 37 weeks is premature. While the actual cause of preterm labour is unknown, many organisations, such as the March of Dimes, continue to do research to find risk factors and causes of preterm birth, and even to prevent it.

Preterm or premature birth is defined as birth occurring before 37 weeks of pregnancy. It is divided into three sub categories:

Mildly preterm (32-37 weeks)
Moderately preterm (28-31 weeks)
Extremely preterm (before 28 weeks)

Risks of Preterm Labour

Because the actual cause of preterm labour is largely unknown, it’s not easy to know who will experience preterm labour. Even so, there are some risk factors that increase the chances of having your baby early:

Smoking, alcohol and drug use: not only do these behaviours increase the risk of preterm birth, they can cause your baby to be born at a low birth weight and/or with other health problems.
Pregnancy conditions (high blood pressure, preeclampsia, diabetes, blood clotting disorders, placental abruption, placenta previa, autoimmune disorders): these conditions can compromise your baby’s growth and oxygen, which can lead to preterm birth.
Vaginal and uterine infections: these infections are believed to cause almost 50% of all preterm labours. Research has shown infections cause inflammation, which triggers the release of certain hormones that initiate labour.
Twin or multiple pregnancies: women carrying more than one baby are more likely to go into labour early. There is a higher incidence of multiples through IVF conception, leading to more preterm IVF births.
Previous preterm labour: you are more likely to have another premature birth if you have already experienced preterm labour.
Family history of preterm labour: if you were born prematurely you are more likely to have a premature baby yourself.
Baby has certain birth defects.
Structural problems with cervix or uterus: if the cervix stays open during pregnancy, or there are abnormal structures of the uterus, preterm labour is more likely to occur.
Gum health: pregnant women are more likely to have periodontal disease, which has been linked to preterm labour. It’s believed the bacteria can enter the bloodstream and trigger preterm labour.
Having short intervals between babies: a large study has shown the closer together your pregnancies are, the greater the risk of preterm labour.
Maternal age: women who are older than 35 are considered to be high risk, because they are more likely to experience premature labour.
High levels of extreme physical stress: women who stand for long periods of time, or have physically stressful jobs, are more likely to go into labour early.

Premature Labour Signs

Preterm labour can sometimes be stopped, or at least delayed, to allow the baby as much time as possible in the uterus. If you experience any of the following signs of premature labour, contact your midwife or doctor immediately:

Backache, usually felt in the lower back area. This can be felt constantly or intermittently, but it doesn’t ease or go away if you change positions or use comfort measures like a heat pack.
Regular contractions coming every 10 minutes or less. Contractions can feel like period cramps or aches, or even similar to cramps you get with a stomach bug.
Changes in the type or amount of vaginal discharge (bloody, mucus or water).
Increasing pressure in your pelvis or vagina.
Any bleeding from the vagina, even spotting.
Any nausea, vomiting or diarrhoea.

Some of these signs – such as backache and pelvic pain – are normal symptoms of pregnancy, but it is always a good idea to contact your doctor or midwife if you are unsure.

What To Do If You Think You Are In Premature Labour

If you suspect you’re having contractions, try sitting down and resting, or changing positions if you are already lying down. Drink a few glasses of water in case you are becoming dehydrated.

Put your fingertips on your stomach; you will feel a contraction as a tightening, then a releasing and softening.
Time each contraction, from the start of one contraction to the start of the next contraction.
This tells you the frequency of contractions; if the interval is 10 minutes or less and occurring regularly, contact your care provider.

Contractions can be confused with Braxton Hicks which you might have already been feeling. These are practice contractions; they are usually quite irregular, they don’t intensify, and they stop when you change position. If you aren’t sure whether your contractions are the real thing, it’s best to contact your doctor or midwife.

If you think your waters have broken, put on a pad (don’t use tampons) and try smelling the liquid. If it doesn’t have any smell it could be amniotic fluid, but if it smells like urine it could be bladder leakage.

If you are in doubt, or have any signs of preterm labour, contact your midwife or doctor for advice. They will ask you some questions and then, if they think it is needed, will ask you to come in for an assessment.

What To Expect

When you arrive at your doctor’s office or the hospital, your baby’s heart rate will be monitored to see if there are any signs of distress, and you will be checked for contractions. You might also have an ultrasound to assess your baby’s growth and size, and to check the amniotic fluid levels.

You will also have a vaginal examination, to check whether the membranes have ruptured and your cervix has begun to thin or open (efface and dilate). During the vaginal examination, your doctor will probably do a swab, to test for any signs of infection.

If these exams show you are not in labour then you will probably be sent home. Most likely you will be told to rest as much as possible. There is no evidence to show regular bed rest can prevent premature labour, and it can have potentially harmful effects.

If you are in premature labour you will remain in hospital. Based on your individual situation, your doctor will decide whether to delay labour or let it continue. In most cases your doctor will try to delay the start of labour for as long as possible. Every day your baby remains in the womb improves the chances of survival, and reduces the chances of complications for your baby.

If your health, or the health of your baby, is at risk, it might be better for your baby to be born early. If you are more than 34 weeks pregnant, or tests have shown that your baby’s lungs are mature enough, labour might be allowed to continue.

Premature Labour Management

In most cases of premature labour the first goal is to delay birth for as long as possible. It might be necessary for you to be transferred to a hospital with a neonatal intensive care unit, where your baby can be cared for if necessary.

If you are less than 34 weeks pregnant, it’s more likely your doctor will try to delay labour for as long as possible. Babies born before 34 weeks gestation are at higher risk for complications of premature birth.

When treatment has been decided on, you will closely monitored, to check your baby’s heart rate and to measure contractions. An intravenous line (IV) will be inserted and you will be given fluids and medications.

Antibiotics may be given as a preventative measure, in case infection is causing labour to begin prematurely. If you haven’t been tested for Group B strep (the test is usually performed after 35 weeks), you’ll be given IV antibiotics to prevent potential transmission of the bacteria to your baby in case you are positive.

Premature Labour Treatment (To Delay Labour)

Medications used to relax the uterine muscle and stop contractions are called tocolytic agents. These medications aim to delay birth for several hours, ideally for 48 hours. They can be given via IV or injection, or taken orally.

Magnesium sulfate

One of the most commonly used and considered the safest.
Side effects are rare but include flushing, nausea, vomiting, headache, weakness, and shortness of breath.
Chest pain and pulmonary edema occur rarely.
It crosses the placenta, so babies can be lethargic, have respiratory depression and low muscle tone (hypotonia).

Terbutaline

A synthetic form of a stress hormone called epinephrine.
This hormone causes smooth muscles, like the uterus, to relax rather than contract.
Side effects can be a racing heartbeat, flushing, tremors, and restlessness.
Around 1-5% of women experience irregular heartbeat, extra fluid in the lungs (pulmonary edema), and chest pain.
It can raise blood sugar levels in diabetic women.
In babies it can raise heart rate and blood sugar levels.
Terbutaline is not recommended for women with heart disease, hyperthyroidism, and poorly controlled diabetes.
It should be noted the FDA does not approve of the use of terbutaline as a tocolytic agent for preterm labour.

Nifedipine

A calcium channel blocker, usually used to treat high blood pressure and chest pain (angina). As a tocolytic agent, nifedipine can stop uterine contractions.
It is administered orally, which allows for rapid absorption, and lasts for around 6 hours.
Side effects can include very low blood pressure (hypotension), increased pulse, headache, flushing, dizziness, nausea, and raised glucose levels.
Babies appear to have less risk of respiratory distress syndrome, necrotizing enterocolitis, and bleeding on the brain, than with other tocolytics.
Although it is not labelled for use as a tocolytic, several randomised studies have found nifedipine to be associated with a more frequent successful prolongation of pregnancy than other tocolytics.

Indomethacin

A non-steroidal anti-inflammatory drug (NSAID) that prevents the body from making prostoglandins – substances which cause contractions.
It can cause indigestion in many women so it should be taken with food.
Women with a history of ulcers, kidney, liver, or bleeding problems should avoid indomethacin.
If used for more than 48 hours it can reduce the amount of fetal urine output, lowering levels of amniotic fluid.
It can also cause a major fetal blood vessel to close prematurely. This can result in serious problems after the baby is born. This is less likely to happen if the drug is used for less than 48 hours, and before 32 weeks of pregnancy.

If tocolytics are used, you will be monitored closely for side effects. If labour stops, you will need to stay in hospital for a while longer, to be monitored for any more contractions. Whether you can return home or need to stay in hospital will depend on how long labour can be delayed.

Treatments For Baby

In case labour can’t be delayed more than a few days, you will be given steroids, to speed the development of your baby’s lungs. Steroids can help the lungs produce more surfactant, which is a substance that helps keep the alveoli (small sacs in the lungs) inflated. This will help your baby to breathe after birth. It also reduces the risk of your baby developing bleeding on the brain and other complications of preterm birth.

Steroids can’t be used before 23 weeks of gestation, as the baby is too immature to receive any benefit. After 34 weeks of gestation, unless tests show your baby’s lungs are not mature, steroids won’t be needed.

When the steroids are given is very important. The first dose is given as an injection into your arm, leg or buttock. Depending on the sort of steroid used, injections are usually given 2-4 times over a 48 hour period.

Human studies haven’t shown any significant risks associated with a single course of steroids. Repeat courses are not recommended, as studies have shown multiple courses of steroids to be linked with babies having lower birth weights and smaller heads.

Premature Labour

Dealing with premature labour is understandably a big shock, and you might feel very stressed and worried about what will happen and concerned for your baby’s health. The good news is that for about 30% of women, preterm labour stops by itself. About 10% of women who go into preterm labour will give birth within a week.

At the hospital you will probably meet a number of staff who will help look after you and your baby after birth. There will be a lot of information to take in and you might feel overwhelmed and anxious. If you need more information, ask your midwife or doctor any questions you might have.

Preterm labour does not automatically mean you will need a c-section. Unless your baby’s health, or yours, is at risk and immediate birth is necessary, you should be able to experience a vaginal birth. Discuss your options with your doctor if a c-section becomes necessary.

You will be monitored throughout your labour, to keep a check on your baby’s heart rate. This can restrict your movements. Ask your midwife to support you to move as much as possible, to help manage contractions. Medicinal pain relief options will probably be limited to epidural or gas, as these medications will not affect your baby’s respiration after birth.

After Birth

Babies who are born between 34-37 weeks tend to do quite well, and might need only some, or even no medical treatment. In this situation, having lots of skin to skin time is ideal. This is called ‘kangaroo care’ and provides the perfect conditions for your baby to bond with you and to develop.

If your baby is born earlier than 34 weeks it’s more likely that special care will be required in the NICU. This can be a distressing and difficult time as you might be able to see your baby only very briefly, immediately after birth. You will be able to visit the NICU and be involved in caring for your baby as much as possible. The staff will assist you and support you during this time.

Premature Labour Prevention

While some women go into labour for reasons we don’t understand, there are ways to reduce your risk of premature birth:

Stop habits that are harmful – such as smoking, drug use or drinking during pregnancy.
If you have a history of preterm labour at less than 37 weeks, you might be able to take a progesterone supplement to prevent preterm labour in future pregnancies. This is begun at 16-26 weeks, and taken until 36 weeks.
Avoid or reduce physical stress. Ask your doctor for supporting medical documentation, if required for your employment.
Be as healthy as possible before and during pregnancy.
Have high quality antenatal care.

A recent review published by The Cochrane Library has shown women who have the same midwife during pregnancy and labour are around 23% less likely to have a premature baby than women who have shared care. Midwifery-led continuity of care is also linked with a lower risk of fetal loss before 24 weeks gestation. Check local organisations to see if primary midwifery care is available in your area.

Premature labour can be very stressful, and it is important to remember that you will be well supported by your doctor and hospital staff. Meeting your baby is a very important time and you are likely to have many conflicting emotions, such as fear, guilt, shock, and grief, as well as excitement and joy at seeing your baby. It’s normal to feel you have missed certain experiences when you go through preterm birth, and you should seek support from your care provider if you feel overwhelmed by your experience.

Recommended Reading: