Is lower dose of intramuscular dexamethasone injection beneficial in reducing neonatal respiratory morbidity for elective caesarean section deliveries at 37 to 38 weeks? An observational study

INTRODUCTION: The use of intramuscular (IM) dexamethasone injections before an elective caesarean delivery at term has been shown in multiple randomized controlled trials to reduce the rates of transient tachypnoea of the newborn, and admission to neonatal care. Recent studies have suggested that a complete course of IM steroids can be associated with long term harmful consequences to the infants born, and there have been studies suggesting that a lower dose of IM corticosteroids can be beneficial. Therefore, we aim to establish if halving the dose of dexamethasone to 12mg can demonstrate any benefit for term elective caesarean section deliveries whilst minimizing foetal exposure.

METHODS: An observational controlled study comparing neonatal respiratory morbidities before and after the single dose 12mg dexamethasone was implemented in our obstetrics and gynaecology centre for term elective caesarean section deliveries. We included singleton pregnancies from 37+0 to 38+6 weeks undergoing elective caesarean section into our study. A total of 674 patients fulfilled the inclusion criteria and were recruited. We compared the rates and duration of admission to neonatal intensive care unit, the need for mechanical ventilation and the rate of transient tachypnoea of the newborn in the first half of 2019 without IM dexamethasone injections against the second half of the year when a single dose IM dexamethasone was given.

RESULTS: IM dexamethasone injection did not show any significant benefit with regards to reducing the admission to neonatal care (OR 0.97, p- value 0.69), admission to neonatal intensive care unit (OR 0.91, p- value 0.80), the need for mechanical ventilation (OR 0.98, p- value 0.95), and the incidence of transient tachypnoea of the newborn (OR1.01, p- value 0.96). There was also no significant difference for the duration of admission in the neonatal intensive care unit for both groups (p- value 0.17).

CONCLUSIONS: This study showed that there was no significant benefit gained from the lower dose antenatal corticosteroids for term elective caesarean section deliveries and considering that there have been long term harmful consequences demonstrated from the higher dose of antenatal corticosteroids at term, this practice should therefore be discontinued until a larger study is done to refute these findings. The use of such dexamethasone should only be a viable option in a research setting.