Measures to reduce the complications

Measures which may be employed include:

• induction of maturity of lungs with maternal corticosteroids; this may be effected in the time bought with tocolytic agents such as salbutamol
• avoiding intrapartum asphyxia, with controlled rapidity of delivery
• avoiding intracranial haemorrhage with the same methods
• particularly important is avoiding hypothermia at or shortly after delivery

Notes:

• infants born preterm (before 37 weeks' gestation) are at high risk of neonatal lung disease and its sequelae
  • the more preterm the baby the greater are the risks, especially when birth occurs before 32 weeks (1)
  • a single course of prenatal corticosteroids reduces the risk of RDS from 26% to 17% (relative risk (RR) 0.66, 95% confidence interval (CI) 0.59 to 0.73) (1)
  • repeat dose(s) of prenatal corticosteroids given to women at risk of preterm birth, compared to no repeat treatment, reduce the occurrence of respiratory distress syndrome (RDS) by 18% and the risk of serious health problems in the first few weeks of life for the infant by 12% (2)
    • for one baby to benefit by not developing RDS, 16 women (95% confidence interval (CI) 11 to 29) would need to be treated with repeat prenatal corticosteroids, resulting in 62 fewer babies with RDS per 1000 women treated.
      • number needed to treat for an additional beneficial outcome (NNTB) for serious neonatal outcome is 39 women, resulting in 26 fewer babies with a serious health outcome per 1000 women treated
      • at birth, the neonatal benefits are associated with a reduction in measures of mean body size (mean weight, head circumference and length) including weight adjusted for gestational age and an increase in the proportion of infants born small for gestational age

Reference:

• (1) Crowther CA, Harding PE.Repeat doses of prenatal corticosteroids for women at risk of preterm birth for preventing neonatal respiratory disease. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD003935
• (2) Walters A, McKinlay C, Middleton P, Harding JE, Crowther CA. Repeat doses of prenatal corticosteroids for women at risk of preterm birth for improving neonatal health outcomes. Cochrane Database of Systematic Reviews 2022, Issue 4. Art. No.: CD003935. DOI: 10.1002/14651858.CD003935.pub5