Fetal scalp blood sampling should be abandoned: AGAINST: Fetal scalp blood sampling in conjunction with electronic fetal monitoring reduces the risk of unnecessary operative delivery

In the 1970s and 1980s, electronic fetal monitoring (EFM) and fetal scalp blood sampling (FBS) were introduced without robust evidence but with the assumption that they could help to reduce the incidence of cerebral palsy caused by intrapartum asphyxia. Disappointingly, the incidence of intrapartum asphyxia was only slightly reduced and cerebral palsy rates among infants born at term remained unchanged. The only observed change was that the caesarean section (CS) rate rose four- to five-fold (Thacker Obstet Gynecol 1995;86:613–20). This was because, although a normal cardiotocograph (CTG) trace is a strong indicator of the absence of intrapartum asphyxia, the interpretation of CTGs carries significant inter-observer and intra-observer variability and a nonreassuring or abnormal CTG may not be associated with fetal acidosis and subsequent asphyxia. A high sensitivity but a low specificity may result in undue interventions such as operative vaginal delivery and emergency CS. A complementary test was necessary to increase the specificity of CTG to reduce the number of unnecessary interventions.