An Assessment of the Value of Fetal Scalp Blood Sampling

Abstract

The value of fetal scalp sampling in reducing perinatal mortality, birth asphyxia and Caesarean section rate was assessed by a retrospective study of 2638 booked patients who were delivered in 1966. By using this technique it is possible that the perinatal mortality rate might be reduced from 15.9 to 15.2 per thousand, i.e., by 2 deaths per year. The incidence of birth asphyxia might be improved, but for this to be significant all patients would require repeated monitoring during labour, since about 40 per cent of asphyxiated babies showed no evidence of clinical fetal distress during labour. Since clinical fetal distress was the main reason for Caesarean section in only 18 booked patients, little experience would be gained in the technique of scalp blood sampling and the value of the results would be suspect, and it is likely that in less than half of these cases would operative delivery be prevented.

Foetal acid-base status in clinical foetal distress and high risk casesThe material in this paper has been taken from an M.D. Thesis submitted to the University of Hong Kong.

“…It is concluded that foetal blood sampling is indicated in these types of cases. THE conventional clinical signs of foetal distress, namely the presence of meconium in the liquor amnii and changes in the foetal heart rate, have been shown to be not sufficiently reliable for the accurate assessment of the foetus (Wood & Pinkerton, 1961;Day, Maddern & Beard, 1968;Farr, 1970). Foetal blood sampling provides direct information about the foetal acid-base balance and gives a more accurate picture of the state of the foetus (Saling, 1966a).…”