Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study (MACS)

Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study (MACS)

In women at 26 to 30 weeks gestation and who are risk for threatened early birth, who have not had their baby by 14 or more days after being given a single course of antenatal corticosteroids (ACS), do repeated courses of ACS every 14 days until 33 weeks' gestational age lower the risk of illness or death in babies compared to repeated courses of placebo. Children are assessed at 2 years and 5 years for neurodevelopmental impairment.

In women at 26 to 30 weeks gestation, who are at increased risk for preterm birth and remain undelivered 14 or more days following a single course of antenatal corticosteroids (ACS), are multiple course of ACS every 14 days until 33 weeks effective in reducing the risk of perinatal or neonatal mortality or significant neonatal morbidity, compared to placebo.

18-24 Month Follow-up: Children (18-24 months corrected gestational age) are assessed with the Bayley Scales of Infant Development (Second Edition) to determine neurodevelopmental impairment.

5 Year Follow-up (MACS-5): Children are assessed using the Child Behaviour Checklist (1 1/2 - 5) and the Behaviour Rating Inventory of Executive Function (Preschool version) to determine neurocognitive function.

Inclusion Criteria:

• Women who have previously received one completed course of ACS, at least 14 days ago and continue to be at increased risk of preterm birth
• Gestational age greater ≥ 26 weeks and gestational age < 31 weeks

Exclusion Criteria:

• Women requiring chronic doses of corticosteroids secondary to medical conditions
• Women with a contraindication to corticosteroids
• Women with clinical evidence of chorioamnionitis (temperature ≥ 38°c)
• Known lethal congenital anomaly (e.g. anencephaly)