Fetal middle cerebral artery Doppler in post term pregnancy: a predicting factor for induction of labor outcome

Abstract

Background: Post term pregnancy necessates IOL to avoid the potential hazards on fetal and maternal outcome. Several factors affect the process of IOL, and there is often great uncertainty regarding its success. Late in pregnancy, vasodilatation of fetal brain vessels occurs as a physiological preparation for the onset of labor. MCA-PI decreases in turn as a preliminary fetal mechanism for adaptation to labor. Objective: We assumed that evaluating MCA-PI prior to to IOL. Methodology: A prospective cohort study, which included 150 post term patients (41-42 weeks), who were admitted to Kasr Al-Ainy Hospital for IOL. Prior to induction, we performed U/S to record MCA-PI, together with CL and EFW. Patients were given 25Mcg misoprostol vaginal tab/6 hours, maximum for 24 hours. Responders phase of labor, by the onset of active uterine contractions. Patients who needed CS before the onset of active labor were excluded. Results: A total of 150 patients were included in the study. 133 cases (88.7%) entered the active phase of labor, while 17 (11.3%) cases failed to enter in the active phase. Both groups were comparable in the parity and BMI. (group 1; 1.29± 0.11) compared to the non-responders (group 2;1.67± 0.13). The mean CL was 25.28± 4.25 & 33.43± 4.8 in groups 1&2 respectively. The mean EFW was 3375.47± 178 & 3722.65± 116.33 in groups 1 & 2 respectively. ROC analysis examined the ability of these parameters in predicting the response to IOL. The cutoff 94.12% , 83.46% for MCA-PI, 26.6, 94.1%, 60% for CL, and, 3555, 94%,83.5% for EFW. WE further included all