Table 1. Definition of appropriate use of interventions, based on WHO recommendations^*.

Domain	ACS	Tocolytics	Magnesium sulphate	Antibiotics
Who	Women at risk of imminent preterm birth (birth is predicted to occur within 7 days starting treatment) with no clinical evidence of infection	Women at risk of imminent preterm birth who are eligible for ACSs administration	Women at risk of imminent preterm birth	Women with PPROM
When	Gestational age from 24 to 34 weeks accurately assessed through ultrasound dating	N/A	Gestational age less than 32 weeks assessed by ultrasound dating	After a definitive diagnosis of PPROM
Where	Health facility where adequate childbirth and preterm newborn care are available (including resuscitation, thermal care, feeding support, infection treatment, and safe oxygen use)	Health facility where adequate childbirth is available	Health facility where adequate childbirth is available	Health facility where adequate childbirth is available
How	Intramuscular dexamethasone or betamethasone (24 mg in divided doses). Single repeat course can be administered if birth does not occur within 7 days of initial dose and there is high risk of preterm birth in the next 7 days	Nifedipine (a calcium channel blocker) is the preferred agent, administered as 10–30 mg initial dose, followed by 10–20 mg every 4–8 hours up to 48 hours or until referral complete	Administer prior to birth or up to 24 hours prior to anticipated birth	Erythromycin-recommended regimen

*Adapted from WHO recommendations on interventions to improve preterm birth outcomes: evidence base [12]; N/A, not applicable.

ACS, antenatal corticosteroid; PPROM, preterm prelabour rupture of membranes; WHO, World Health Organisation.