When Are Antenatal Steroids Recommended During Pregnancy?

Introduction

Preterm labour, defined as labour that begins before 37 weeks of pregnancy, is a leading cause of neonatal morbidity and mortality worldwide. Preterm infants are at significant risk of complications due to the underdevelopment of critical organs, especially the lungs. One of the most effective interventions in preventing these complications is the administration of antenatal steroids.

Antenatal steroids, typically betamethasone or dexamethasone, are given to pregnant women at risk of preterm labour to promote the maturation of the fetus’s organs, particularly the lungs. This treatment is essential in improving neonatal health outcomes, preventing conditions like respiratory distress syndrome (RDS), and reducing the overall risk of preterm birth complications.

In this article, we will provide a comprehensive guide on antenatal steroids, including their role in preterm labour management, how they work, when they are recommended, and the associated benefits and risks.

What Are Antenatal Steroids?

Antenatal steroids are corticosteroid medications that are administered to pregnant women at risk of preterm birth. The most commonly used antenatal steroids are betamethasone and dexamethasone, both of which are highly effective in promoting fetal lung development. The primary function of these steroids is to accelerate the maturation of the fetal lungs, which are often underdeveloped in preterm infants.

These steroids are typically administered through injections, with the standard regimen consisting of two doses given 24 hours apart. Once administered, the steroids cross the placenta and stimulate the fetus’s lungs to produce surfactant, a substance that helps the lungs stay inflated and facilitates effective breathing after birth.

In addition to promoting lung development, antenatal steroids can also reduce the risk of other complications associated with preterm birth, such as intraventricular haemorrhage (IVH), necrotising enterocolitis (NEC), and patent ductus arteriosus (PDA).

Why Are Antenatal Steroids Important for Preterm Birth Management?

1. Prevention of Respiratory Distress Syndrome (RDS)

Respiratory distress syndrome (RDS) is a major concern for preterm infants, as their lungs are often underdeveloped and unable to produce enough surfactant. Without sufficient surfactant, the lungs can collapse, leading to difficulty breathing and the need for mechanical ventilation.

Antenatal steroids help prevent RDS by stimulating the production of surfactant in the fetal lungs. By increasing the production of surfactant, antenatal steroids help the lungs remain open and functional after birth, reducing the severity of RDS and improving the infant’s ability to breathe independently.

Studies have shown that antenatal steroids reduce the incidence of RDS by up to 50%, significantly improving survival rates for preterm infants. (World Health Organization, 2023)

2. Reduction of Other Preterm Birth Complications

In addition to improving lung function, antenatal steroids reduce the likelihood of other complications that preterm babies often face. These include:

Intraventricular haemorrhage (IVH): Bleeding in the brain, which is more common in premature infants.

Necrotising enterocolitis (NEC): A gastrointestinal condition that affects preterm babies.

Patent ductus arteriosus (PDA): A heart defect that is often seen in premature infants.

By enhancing the development of critical organs such as the brain, intestines, and heart, antenatal steroids help reduce the occurrence of these life-threatening conditions, leading to better neonatal health outcomes. (Royal College of Obstetricians and Gynaecologists, 2023)

3. Improved Long-Term Health Outcomes

The benefits of antenatal steroids extend beyond the immediate neonatal period. Research has shown that babies who were exposed to antenatal steroids in utero tend to have improved cognitive function, better motor development, and a lower incidence of behavioural problems.

For example, babies who received antenatal steroids have a reduced risk of cerebral palsy, learning disabilities, and attention deficit disorders compared to those who did not receive the treatment. These long-term benefits highlight the importance of antenatal steroids not only in saving lives but also in improving the quality of life for preterm infants. (Mayo Clinic, 2023)

When Are Antenatal Steroids Administered During Pregnancy?

1. Indications for Antenatal Steroids

Antenatal steroids are recommended when there is a risk of preterm birth, typically when the pregnancy is threatened by early labour. The following situations often warrant the administration of antenatal steroids:

Threatened preterm labour: If a woman shows signs of labour before 34 weeks of gestation, especially if the likelihood of delivering prematurely is high.

Multiple pregnancies: Women carrying twins, triplets, or more are at increased risk of preterm birth and may benefit from antenatal steroids.

Preterm premature rupture of membranes (PPROM): If the membranes rupture prematurely (before 37 weeks), increasing the likelihood of preterm labour.

The steroids are most effective when administered between 24 and 34 weeks of gestation. However, they can be given later in pregnancy if there is a significant risk of preterm birth. (Royal College of Obstetricians and Gynaecologists, 2023)

2. Timing and Administration

Antenatal steroids are usually administered in two injections, given 24 hours apart. The injections are typically administered in a hospital setting, with the mother receiving the treatment under the supervision of medical professionals. The steroids cross the placenta and begin to work within 24-48 hours, although the full benefits can last up to seven days.

The timing of antenatal steroid administration is crucial. The treatment is most effective when given between 24 and 34 weeks, as this is when the fetus’s lungs are most responsive to the effects of the steroids. After 34 weeks, the lungs are typically more developed, and the benefit of antenatal steroids is reduced. (American College of Obstetricians and Gynecologists, 2023)

Risks and Side Effects of Antenatal Steroids

While antenatal steroids are generally safe, there are some risks and side effects that expectant mothers and healthcare providers should consider.

1. Potential Risks for the Mother

The most common side effect for the mother is an increase in blood sugar levels. Women with gestational diabetes or pre-existing diabetes are particularly vulnerable to this effect. Elevated blood sugar levels can lead to complications like hyperglycaemia, but these effects are usually short-lived and resolve once the steroids are stopped.

Antenatal steroids may also suppress the immune system, increasing the risk of infections, but this is generally a minor concern. Overall, the risks to the mother are minimal, especially when the treatment is administered under careful medical supervision. (American Pregnancy Association, 2023)

2. Potential Risks for the Baby

There are some concerns about the long-term effects of antenatal steroids on babies. Some studies suggest that infants exposed to antenatal steroids may be at a slightly increased risk of asthma, wheezing, or other respiratory issues later in childhood. However, the risk remains relatively low, and the benefits of antenatal steroids in reducing respiratory distress syndrome (RDS) and other preterm birth complications far outweigh this minor concern.

There are also concerns about behavioural effects, such as hyperactivity or developmental delays, but the research on these effects is inconclusive. Most studies show that antenatal steroids have no significant impact on the long-term health of the child. (National Institutes of Health, 2023)

The Role of Antenatal Care in Preterm Birth Management

1. Comprehensive Antenatal Care

While antenatal steroids are a critical part of preterm birth management, they are just one component of a comprehensive antenatal care plan. Regular antenatal checkups, antenatal scans, and antenatal appointments are essential to monitor the health of both the mother and the baby, particularly when there is a risk of preterm birth. These appointments allow healthcare providers to assess the pregnancy, identify potential risks, and make informed decisions regarding treatments like antenatal steroids.

In addition to medical treatments, antenatal care also includes emotional and psychological support. Expectant mothers are encouraged to engage in activities like prenatal yoga, pregnancy massage, and other relaxation practices that promote overall well-being during pregnancy. (My Expert Midwife, 2023)

2. Education and Preparation

Antenatal education is a key part of pregnancy care. Antenatal classes provide expectant parents with valuable information about childbirth, neonatal care, and managing the risks associated with preterm birth. These classes help parents understand the role of antenatal steroids and other medical interventions, giving them the knowledge they need to make informed decisions.

Participating in antenatal education also helps expectant parents feel more prepared and confident, whether it’s understanding how antenatal steroids work or learning about other treatments that may be necessary. (NHS, 2023)

Conclusion

Antenatal steroids are an essential tool in managing preterm labour, improving neonatal health outcomes, and reducing the risks associated with premature birth. These steroids play a key role in promoting lung development, preventing respiratory distress syndrome (RDS), and reducing the likelihood of other complications. While there are some risks associated with their use, these are minimal and manageable when the steroids are administered under medical supervision.

Expectant parents should work closely with their healthcare providers to understand when antenatal steroids may be recommended, the benefits they offer, and the role they play in a comprehensive antenatal care plan. By staying informed and engaged in antenatal education, parents can ensure the best possible outcome for their baby.