Assessment of fetal scalp sampling in labor

One hundred and forty-six cases have been followed in labor by means of fetal scalp samples. Fifty-six of these cases showed clinical signs of fetal distress. Mean values for pH, pCO 2 , and base deficit did not differ in the "distressed" and "nondistressed" group. Severe fetal acidosis (pH 7.10) was encountered infrequently. Actual pH of the fetus in the range observed in these cases was not related to the immediate state of the newborn. The presence of a normal pH in the presence of suspected fetal distress may allow a more conservative approach to avoid surgical intervention in these situations. No precise measure of acid-base status is suggested as a firm indication for intervention in suspected fetal distress.