[Clinical analysis of continuous electronic fetal heart rate monitoring for preterm small for gestational age during labor]

Abstract

Objective: To investigate the clinical value of continuous electronic fetal heart rate (FHR) monitoring for preterm small for gestational age (PSGA) during labor.

Methods: Three hundred and three pregnant women who had inevitable preterm labor at 32 - 36 weeks' gestation because of premature rupture of membrane or unknown cause underwent continuous electronic FHR monitoring during labor from Jan 2002 to May 2004. In total, 78 newborns were preterm small for gestational age (PSGA, PSGA group) and 225 newborns were preterm appropriate for gestational age (PAGA, PAGA group). The cardiotocography (CTG), outcome of labor, and cases with combined umbilical cord abnormality of both groups were analysed retrospectively.

Results: The number of cases with pure U type variable deceleration of PSGA group and PAGA group was respectively 24 (30.8%) and 10 (4.4%) (P < 0.01). The number of cases of U type variable deceleration accompanied with other abnormal CTG of both groups was respectively 10 (12.8%) and 1 (0.4%) (P < 0.01). Of PSGA group, the rate of cesarean section and forceps among cases of pure U type variable deceleration was lower than that of cases with U type variable deceleration accompanied with other abnormal CTG (20.8% vs 60.0%, P < 0.05. While, the rate of umbilical cord abnormality (44.1%) among 34 cases with U type variable deceleration was higher compared with that (20.5%) among 44 cases without U type variable deceleration (P < 0.05).

Conclusions: U type variable deceleration is the characteristic FHR graph of PSGA during labor and is not the sign of fetal distress when not accompanied with other abnormal CTG.