Introduction:
Premature birth is a serious problem for public health. Even in the final months and weeks of pregnancy, a developing infant experiences significant growth. Premature delivery, sometimes called preterm birth, occurs when a baby is delivered before the full 37 weeks of pregnancy. A baby is more likely to die or have a major impairment the earlier it is born. The primary prevention of preterm birth is still the major objective. However, it is crucial to lessen the effects of preterm birth on infant morbidity and death until a better knowledge of the mechanisms behind preterm birth leads to its effective and widespread prevention. One of the most crucial prenatal therapies in obstetrics is administering antenatal corticosteroids to fetuses born preterm.
What Is Antenatal Corticosteroids?
Antenatal steroids, called antenatal corticosteroids, are drugs for pregnant women anticipating a preterm birth. Antenatal refers to the medical treatment provided to expectant mothers before the birth of their children. When these steroids are given, the fetus's lungs develop more quickly, which lowers the risk of newborn respiratory distress syndrome and infant death. During a randomized control experiment employing Betamethasone, Sir Graham Liggins and Ross Howie first proved the corticosteroid treatment's efficacy on humans in 1972.
What Is the Best Antenatal Corticosteroid?
Dexamethasone and Betamethasone have both shown promise in aiding fetal maturation. Betamethasone is provided as two doses of 12 mg given intramuscularly, separated by a period of 24 hours, and is a mixture of Betamethasone sodium phosphate and Betamethasone acetate. Four 6mg intramuscular doses of dexamethasone sodium phosphate are given, each 12 hours apart. When used briefly, these drugs share a similar molecular makeup and are fluorinated chemicals with modest immunosuppressive and mineralocorticoid effects.
How Effective Are Antenatal Corticosteroids in Particular Populations?
There are still uncertainties regarding the effectiveness of antenatal corticosteroids in particular patient categories, even if their ability to enhance outcomes for singleton (pregnancy with just one baby) infants after preterm birth has been shown.
Multiple Gestation:
Preterm birth is substantially more likely in patients who have had many pregnancies. Due to various variables that include a greater frequency of obstetrical complications like preterm labor and preterm rupture of membranes, as well as a higher incidence of maternal illnesses like preeclampsia, individuals with multiple gestations are more likely to give birth preterm.
The most recent Cochrane study found that prenatal corticosteroids did not significantly lower the incidence of RDS (respiratory distress syndrome), IVH (intraventricular hemorrhage), or newborn death for women carrying multiple pregnancies. Antenatal corticosteroids may be less effective in multiple gestations for physiological reasons. According to some authors, multiple gestations may result in a dilutional influence on the amount of medications reaching the fetuses due to more excellent dispersion in the maternal and fetal compartments.
The most recent research does not support the effectiveness of antenatal corticosteroids in multiple gestations. Nevertheless, due to the strength of the evidence in singleton gestations, recommendations generally favor administering corticosteroids in these pregnancies with a potential for preterm birth.
Obese Women:
Although the majority of research has not discovered a substantial correlation between obesity and spontaneous preterm delivery, obesity is an independent risk factor for a variety of distinct unfavorable obstetric outcomes. The need to administer antenatal corticosteroids to an obese patient is still frequent in obstetrical treatment due to the high frequency of obesity. It has been speculated that obesity may affect the efficiency of antenatal corticosteroids due to variations in distribution among tissues and medication removal, just like in multiple gestations.
However, Hashima and associates discovered that body mass index (BMI) did not affect the neonatal prognosis in women taking a single course of antenatal corticosteroids. Due to this, despite potential concerns, there is no evidence to support a different antenatal corticosteroid regimen based on maternal BMI.
Restriction of Intrauterine Fetal Growth (IUGR):
Concerning the effectiveness of antenatal corticosteroids for pregnancies complicated by fetal growth limitation, the research appears inconclusive. An extensive population-based investigation of newborns with IUGR revealed that the advantages of antenatal corticosteroids were comparable to those observed in infants with average growth. In addition to considerable controversy regarding the effectiveness of antenatal corticosteroids for fetuses with growth restrictions, there is some uncertainty regarding the safety of treatment in this population.
Extremely Early Preterm:
Extremely preterm baby survival has increased due to recent improvements in neonatology and obstetrical care. As a result, resuscitation of preterm newborns under 24 weeks of gestation has increased in frequency. The use of antenatal corticosteroids at 23 weeks of gestation and earlier has increased despite the lack of convincing evidence for their benefits in this population.
Preterm Premature Rupture of Membranes (PPROM):
Numerous clinical investigations that assessed antenatal corticosteroid therapy following preterm PROM found that it decreased infant mortality, respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis. According to recent evidence, antenatal corticosteroids are not linked to higher maternal or newborn infection risks regardless of gestational age.
What Is Rescue Course in Antenatal Corticosteroid Therapy?
Despite the lack of evidence to back it, one tactic that appears to have gained widespread clinical acceptance is to give pregnant women a "rescue" course of antenatal corticosteroids. Individuals who obtain a beginning course of antenatal corticosteroids but fail to deliver within seven to 14 days are eligible for one further round of corticosteroids, known as the "rescue" course. It is unclear if it is prudent to administer this rescue course after seven days, 14 days, or longer, given shortcomings in the information on the timing of corticosteroid effectiveness. Additionally, it is unclear whether this interval should change based on when the original course is administered, whether the rescue course should be given regularly, or only if preterm birth occurs.
Is It Safe to Use Antenatal Corticosteroids?
No substantial short-term fetal or neonatal side effects are linked to a single course of antenatal corticosteroids. According to research, the fetal death rate was not different between exposed and unexposed groups. Antenatal corticosteroids do not affect the neonate's birth weight or the likelihood of contracting an infection in the critical care unit. There have been no severe maternal side effects associated with antenatal corticosteroid use.
A single course of prenatal corticosteroids has no particular contraindications. The immunosuppressive effect could worsen systemic infection or reactivate latent disease, which is cause for concern. Although no evidence supports it, active tuberculosis has been proposed as a potential contraindication for antenatal corticosteroid treatment.
This will be fine in affluent nations as frequently as in those where antenatal corticosteroid administration is still a relatively uncommon practice. It is crucial to closely monitor the safety of corticosteroid therapy in developing nations as use rises.
Conclusion:
Preterm birth is still a serious public health issue. One of the most significant therapies in obstetrics is the prescription of antenatal corticosteroids to improve outcomes following preterm birth. Antenatal corticosteroids are effective for singleton pregnancies between 26 and 34 weeks gestation at risk for preterm birth, but there are still concerns about their usefulness in certain patient populations. Despite the substantial quantity of data that has been gathered on antenatal corticosteroids, additional research is still required to optimize the use of this therapy and enhance outcomes for those at risk.
