Association of Obstetrical Variables with Induction to Expulsion Interval in Misoprostol-Induced Mid-Trimester Abortion

Abstract

Objective: To investigate significance association of obstetric history (maternal age, gravidity, parity, gestational age & previous LSCS) with induction to expulsion interval (IEI) in Misoprostol-induced- Mid-Trimester (MI-MT) abortion cases. Methodology: This prospective cohort study was conducted at CMH Nowshera from January 2014- June 2015. One hundred and six candidates were included. Termination of pregnancy was carried out with Misoprostol using two regimens. Regimen A included 400ug Misoprostol given 6 hourly with maximum of 4 doses for 24 hours for gestational age 13-20 weeks. In Regimen B 200ug Misoprostol with the same protocol was given for gestational age 21-26 weeks. Failure of induction was considered after 72 hours. Cohort was stratified according to categorical variables of maternal age, parity, gravidity, gestational age and previous LSCS. Outcome variable was Induction to expulsion interval (IEI). Results: Null hypothesis (H0) of no significant association between obstetrical variables (maternal age, parity, gravidity, gestational age, previous LSCS) and outcome variable (IEI) was tested using chi square and Fisher’s exact tests with 1000 bootstrapping. Simpson's paradox effect was adjusted using Restriction method. Significant associations were found between gravidity, gestational age and previous LSCS with IEI (P value <0.05), that is, lower gravidity; higher gestational age and presence of previous LSCS were associated with longer IEI. Conclusion: This study emphasized the significance of obstetric history in MI-MT abortion cases. It also emphasized important obstetrical parameters to consider hence provide guidance to clinicians and researchers for counseling, antenatal care and treatment in such cases