Fetal scalp and cord blood lactate

Lactate measurements have been evaluated in intrapartum fetal surveillance for some 30 years. However, it was not until reliable, handheld, microvolume devices were launched during the 1990s that lactate became a clinical option. Retrospective data suggest that lactate determinations in fetal scalp blood are better than pH for predicting severe neonatal morbidity. A randomised controlled trial comparing these two measurements found lactate to be more favourable in clinical practice in terms of less sampling failure and reduced time from the decision to do a fetal scalp blood sample to the clinician receiving the result. At present, a large multicenter randomised control trial is in progress in Sweden to compare lactate and pH measurement for the clinical management of suspected fetal compromise. Main end-points in the study are metabolic acidemia or pH <7.00 in cord arterial blood at delivery. Results are likely to be available in 2–3 years time.