Aim: To investigate whether cerebroplacental ratio (CPR) can be a useful marker to predict non-reassuring fetal status (NRFS) in small for gestational age (SGA) infants at term.
Material and methods: Three hundred and nine singleton SGA infants delivered between 37 and 41 weeks of gestation were included in this study. SGA infants were defined as birthweight less than 10th percentile for gestational age. Doppler measurements were recorded once a week until delivery. The incidence of NRFS or an emergency cesarean delivery, and relationship between CPR and NRFS in SGA infants were compared with appropriate for gestational age (AGA) infants at term, and a receiver-operator characteristics curve analysis was performed.
Results: The incidences of NRFS was significantly higher in SGA (27.8%) infants compared with in AGA infants (18.0%), and the rate of emergency cesarean delivery was significantly higher in SGA (14.6%) infants compared with AGA infants (8.3%). CPR was obtained from 63 SGA infants, and 16 out of 63 cases (25.4%) resulted in NRFS. The infants complicated with NRFS showed significantly lower CPR values compared with those without NRFS (1.05 ± 0.2 vs 1.23 ± 0.2, P = 0.013), while middle cerebral artery resistance index and 'umbilical artery resistance index were not statistically different between the two groups. A cut-off value of CPR 1.1 based on the receiver-operator characteristics curve provided the best combination with 62.5% sensitivity and 74.5% specificity to predict NRFS occurrence.
Conclusions: The SGA infants complicated with NRFS showed significantly lower CPR values compared with those without NRFS.
© 2011 The Authors. Journal of Obstetrics and Gynaecology Research © 2011 Japan Society of Obstetrics and Gynecology.