THE INTRAPARTUM CTG PRIOR TO NEONATAL ENCEPHALOPATHY AT TERM - A CASE-CONTROL STUDY

Objective To compare cardiotocograph (CTG) records during labour in ca ses of neonatal encephalopathy and matched controls. Design Case-contr ol study. Setting Metropolitan area of Perth, Western Australia. Subje cts Term deliveries complicated by neonatal encephalopathy and control s matched for sex, hospital, time of birth, day of week of birth and m aternal health insurance. Main outcome measures Low fetal heart rate ( FHR) variability, FHR accelerations, late decelerations, total Kreb's score and FIGO classification of CTG records. Results The neonatal enc ephalopathy group had significantly more abnormal CTG records (89%) cl assified according to FIGO, although 52% of control CTG records were a lso abnormal. CTG records from cases developed significant differences in terms of absence of FHR accelerations and low FHR variability, but not late decelerations, prior to delivery. Conclusion Given the low i ncidence of neonatal encephalopathy in this study (7 per 1000) the pre dictive value of an abnormal CTG record is clinically unhelpful. Howev er, the changes in the FHR in such cases suggest a greater disturbance of fetal (rest-activity) behaviour during labour.