Abstract
The ineffectiveness of labour induction by oxytocin in prenatal rupture of the membranes at term (TermPROM) can be associated with unfavourable birth canal. However, expectant management of TermPROM assumes the absence of vaginal examination due to the high risk of complications. Complex ultrasound (CUS) was found to justify the use of Misoprostol to reduce the frequency of Caesarean section (CS). A prospective controlled trail in nulliparas admitted with TermPROM. The length of the cervical canal (CL) was measured transperineally, anteroposterior distance of the lower uterine segment (APD) - transabdominally. The CS probability was found by the binomial logistic regression model formula: p = 1/(1+e-z), where z = -3,836 + 0,253xAPD + 0,638xCL (sensitivity – 98.6%, specificity – 93.5%, prognostic value of a positive result – 97.2% and a negative result – 96.7%). VP45.06: Table 1. Classifications (n = 64) True positives 32 96,97±2,98% False positives 1 3,03±2,98% 33 51,56±6,25% False negatives 2 6,45±4,41% True negatives 29 93,55±4,41% 31 48,44±6,25% 34 53,12±6,24% 30 46,88±6,24% 64 100% Of the 64 enrolled patients with unfavourable birth canal, 33 received oral Misoprostol (Misoprostol group - MG). 31 pregnant women of the control group (CG) were managed according to the regular protocol. There were no differences in age, body mass index, pregnancy parity, gestational age, frequency of extra- and genital pathology in the groups (p> 0.05). Considering APD and CL, no differences were found in the groups, which indicates the homogeneity of the test material (p> 0.05). 96.7 ± 2.98% of MG had a vaginal birth (VB). The proportion of natural births in the MG group was higher than in the CG (Relative risk 6,5% 95%CI 1.74 – 25.45%, relative risk reduction 93.35% 95%CI 74.55 – 98.26%). The use of CUS can reduce the CS rate at TermPROM via justification the taking of Misoprostol. These results need validation in a larger scale study.