INTRODUCTION
Preterm birth (less than 37 weeks’
gestation) accounts for around 11% of all live births worldwide, poses
risks of adverse outcomes and can be attributed 35% of deaths among
newborns.1-3 Preterm
birth represents a significant health burden worldwide, mainly in
Low-to-Middle-Income Countries (LMICs).
Respiratory distress Syndrome (RDS) is a serious complication of preterm
birth and the primary cause of early neonatal death, lifelong disability
and poor quality of life. RDS affects up to half of babies born before
28 weeks and a third of babies born before 32
weeks.4 Antenatal
corticosteroids for preterm birth prevent RDS and neonatal
mortality5, however
there still persist doubts about
the applicability in
LMICs6 and there is no
consensus regarding the type of corticosteroid to use; nor the dose,
frequency, timing of use or the route of administration. Currently,
either betamethasone or dexamethasone are the recommended corticosteroid
for clinical practice. The World Health Organization (WHO)
guidelines7 states that
there is no conclusive evidence that would support a recommendation of
one over the other. We acknowledged that dexamethasone has an advantage
over betamethasone in terms of lower cost and wider availability, and it
is currently listed on the WHO Essential Medicine List and in WHO’s
Managing complications in pregnancy and childbirth
guide.8
Two Cochrane systematic reviews have synthesized the effects of
corticosteroids. Brownfoot et al.
20139 and Roberts et al.
201710, which compared
any corticosteroids for preterm birth against each other, or against
placebo, respectively. Although Brownfoot et
al.9 focused on direct
comparisons, authors also assessed indirect comparisons of
corticosteroids with placebo for some outcomes based on Roberts
200611. While the
indirect estimates suggest no significant differences between
corticosteroids for puerperal sepsis, a significant difference favoured
betamethasone for
chorioamnionitis.11
Direct comparisons in Brownfoot
20139 showed that
dexamethasone may have some benefits compared to betamethasone such as
less intraventricular haemorrhage. Roberts
201710 suggested that
dexamethasone may also be associated with a higher rate of
chorioamnionitis. New additional published
trials12-14, that
almost doubled the previous number of participants involved in direct
comparisons, warranted a network meta-analysis (NMA), to urgently define
this hot topic. Our aim was to assess the comparative clinical
effectiveness and safety of dexamethasone versus betamethasone for women
at risk of preterm birth.