The relationship between maternal placental growth factor levels and intrapartum fetal compromise

Whilst some cases of intrapartum fetal compromise are the result of unpredictable catastrophic events, the majority arise from an unrecognised reduction in feto-placental reserve in otherwise healthy pregnancies. There is currently no reliable technique prior to labour that identifies the at-risk fetus. We aimed to investigate the relationship between maternal levels of serum placental growth factor (PlGF) and intrapartum fetal compromise in term pregnancies prior to labour. Secondary outcomes were caesarean delivery for intrapartum fetal compromise and adverse neonatal outcomes.

A blinded, prospective, cross sectional study set at Mater Mother's Hospital, Brisbane, Australia. Maternal PlGF concentration was assessed fortnightly from 36 weeks until delivery in 378 low-risk pregnant women. Antenatal and intrapartum care was managed according to local protocols and guidelines, and intrapartum and neonatal outcomes were recorded.

Pregnancies that developed intrapartum fetal compromise had lower PlGF than those that did not. PlGF concentration was also lower amongst pregnancies that developed intrapartum fetal heart rate abnormalities, were delivered with abnormal cord gases or Apgar ≤7 at 5 min. Additionally, PlGF levels were lower in pregnancies with an adverse composite neonatal outcome.

Lower maternal PlGF concentration is associated with intrapartum fetal compromise and poorer condition of the newborn. Maternal PlGF levels may be useful as a component of a risk stratification tool for intrapartum fetal compromise in apparently 'low risk' term pregnancies prior to labour.