European Journal of Cardiovascular Medicine

Induction of labor represents the stimulation of the regular contraction of the uterus before the spontaneous labor onset using the pharmacological or mechanical methods to attain progressive dilatation of the cervix followed by the subsequent delivery. Labor induction has been a common and vital procedure being routinely performed in the clinical obstetrics. Concerning India, the incidence for induction of labor various with geographical areas and healthcare centers and is reported in the range of 5-22% of all the admissions to the labor rooms. In general, induction of the labor is indicated din conditions when benefits of termination of pregnancy are higher compared to the risks of pregnancy continuation.¹

Among the conventional indications for the induction of labor, postdated pregnancies and pregnancy induced hypertension are the most common indications that contribute to >80% of the reported induction of the labor. The most accurate time for induction of labor is the time when perinatal or maternal advantages are higher with interruption of the pregnancy compared to the continuation of the pregnancy. The overall rate of the success for induction of labor following NICE guidelines are <2/3^rd of females having vaginal delivery with no further invasive management with nearly 22% requiring emergency cesarean delivery and 15% needing operative vaginal delivery.²

Various maternal complications as maternal intensive care unit admission need, injury to bladder and bowel, deep venous thrombosis, need for blood transfusions, urinary tract infections, fever, postpartum hemorrhage, and wound infections and fetal complications as respiratory distress syndrome, meconium aspiration syndrome, meconium-stained liquor, birth asphyxia, low Apgar in five minutes, neonatal intensive care unit admission, neonatal morbidity and early mortality, and/or low birth weight are significantly higher with emergency cesarean sections compared to elective cesarean sections.³       

To reduce the rates of overall fetal and maternal mortality and morbidity, it is vital to identify any associated factor which can be helpful in prediction of the success of the labor and induction, and hence, reducing the risk of exposure to various complications linked to emergency cesarean section. With increasing incidence of labor induction, need for emergency cesarean section is raised owing to failure in labor induction.⁴ The present study was aimed to assess the impact of Induction Indications on Delivery Outcomes and modes. The study also assessed the degree of perinatal, fetal, and maternal morbidity with each indication for labor induction.

The present retrospective observational study was aimed to assess the impact of Induction Indications on Delivery Outcomes and modes. The study also assessed the degree of perinatal, fetal, and maternal morbidity with each indication for labor induction. The study subjects were from Department of Obstetrics and Gynaecology of the Institute. Verbal and written informed consent were taken from all the subjects before study participation.

The study included 200 pregnant females that had underwent induction of labor at the Institute within the defined study period. In all the participants, indications of induction of labor were recorded. All the prerequisites for induction of labor were checked in all the subjects. In all included females, recent obstetric ultrasound, basic investigations, vaginal examination, pelvic assessment, obstetrical assessment, and general history was assessed and recorded.

The primary outcomes assessed in study subjects was cesarean section, operative vaginal delivery, normal vaginal delivery, and mode of delivery in pregnant females. The secondary outcomes assessed in study subjects included indications of cesarean section, neonatal and maternal complications concerning the indications for induction of the labor. In all subjects, association in mode of delivery and indication of induction was noted.

The indications for induction of labor were IUGR (Intrauterine growth restriction): In these subjects, fetal weight was <10^th centile assessed from serial growth charts and ultrasound, rhesus isoimmunisation, polyhydramnios and oligohydramnios, postdated pregnancy with gestation >40 weeks, PROM (Premature rupture of membranes), PIH (pregnancy induced hypertension) under hypertensive disorders of pregnancy, and diabetes and pregnancy.⁶

Different methods for induction of labor were medical pharmacological methods as oxytocin infusion and prostaglandin and surgical methods as stripping of membranes and ARM (artificial rupture of membranes). In present study, combined use of surgical and medical methods was used for better efficacy of induction and reduced delivery interval.

The collected data from pregnant females were statistically assessed using the chi-square test, Fisher’s exact test, Mann Whitney U test, and SPSS (Statistical Package for the Social Sciences) software version 24.0 (IBM Corp., Armonk. NY, USA) using ANOVA, chi-square test, and student's t-test. The significance level was considered at a p-value of <0.05.

The present retrospective observational study was aimed to assess the impact of Induction Indications on Delivery Outcomes and modes. The study also assessed the degree of perinatal, fetal, and maternal morbidity with each indication for labor induction. The present study assessed 200 pregnant females that underwent induction of labor at the Institute within the defined study period for delivery modes and indications.

Table 1: Clinical and obstetric parameters in study subjects

It was seen that for 200 pregnant females included in the study, cesarean section, operative vaginal delivery, and normal vaginal delivery was done in 74, 44, and 82 subjects respectively. Rhesus isoimmunisation was seen in 14 subjects where CS (cesarean section), operative vaginal delivery, and normal vaginal delivery was done in 42.85% (n=6), 14.28% (n=2), and 42.86% (n=6) study subjects respectively. Polyhydramnios was seen in 12 subjects where 33.3% (n=4), 16.6% (n=2), and 50% (n=6) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively. IUGR was seen in 16 subjects where 62.5% (n=10) subjects delivered with CS and 37.5% (n=6) with normal vaginal delivery and neonatal complications were seen in 25% (n=4) study subjects. Oligohydramnios was seen in 16 subjects where 37.5% (n=6), 25% (n=4), and 37.5% ((n=6) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and neonatal and maternal complications were seen in 25% (n=4) an 12.5% (n=2) subjects respectively (Table 1).

The study results showed that in postdated pregnancies, there were 40 subjects where 30% (n=12), 25% (n=10), and 45% (n=18) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and neonatal and maternal complications were seen in 20% (n=8) and 30% (n=12) subjects. There were 20 hypertensive females in the study where 30% (n=6), 20% (n=4), and 50% (n=10) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and maternal morbidity was seen in 40% (n=8) females. Diabetes was reported in 28 females where 57.14% (n=16), 14.28% (n=4), and 28.57% (n=8) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and maternal morbidity was seen in 7.14% (n=2) subjects. PROM was seen in 54 subjects where 25.9% (n=14), 33.3% (n=18), and 28.57% (n=8) subjects underwent delivery by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery and maternal morbidity was seen in 7.14% (n=2) study subjects (Table 1).

It was also seen that highest induction rate of 27% was seen associated with PROM followed by 20%, 14%, 10% and 29% with postdate, diabetes, hypertension, and others. Normal vaginal delivery rates were highest with hypertension in pregnancy and polyhydramnios with 50% each followed by postdated and rhesus isoimmunization with 45% and 43% respectively. This was followed by PROM, diabetes, and IUGR with 41%, 28%, and 37% subjects respectively. In 200 subjects assessed in the study, highest cesarean section was done in fetus with IUGR and diabetes mellitus. The study results also showed that concerning 200 subjects that delivered, 50 neonates needed admission to the neonatal intensive care unit where 38 subjects were assessed for short duration and 12 subjects had low Apgar score.

The present study assessed 200 pregnant females that underwent induction of labor at the Institute within the defined study period for delivery modes and indications. It was seen that for 200 pregnant females included in the study, cesarean section, operative vaginal delivery, and normal vaginal delivery was done in 74, 44, and 82 subjects respectively. The design of the present study correlated with the studies of Kumar B et al⁵ in 2021 and Sharda P et al⁶ in 2021 where study design and number of cesarean and vaginal deliveries comparable to the present study were also reported by the authors in their respective studies.

 The study results showed that for rhesus isoimmunisation was seen in 14 subjects where CS (cesarean section), operative vaginal delivery, and normal vaginal delivery was done in 42.85% (n=6), 14.28% (n=2), and 42.86% (n=6) study subjects respectively. Polyhydramnios was seen in 12 subjects where 33.3% (n=4), 16.6% (n=2), and 50% (n=6) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively. IUGR was seen in 16 subjects where 62.5% (n=10) subjects delivered with CS and 37.5% (n=6) with normal vaginal delivery and neonatal complications were seen in 25% (n=4) study subjects. Oligohydramnios was seen in 16 subjects where 37.5% (n=6), 25% (n=4), and 37.5% ((n=6) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and neonatal and maternal complications were seen in 25% (n=4) an 12.5% (n=2) subjects respectively. These results were consistent with the findings of Beshir YM et al⁷ in 2021 and Kumari J et al⁸ in 2021 where results concerning rhesus isoimmunisation, polyhydramnios, IUGR, and oligohydramnios reported by the authors was comparable to the results of the present study. 

It was seen that in postdated pregnancies, there were 40 subjects where 30% (n=12), 25% (n=10), and 45% (n=18) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and neonatal and maternal complications were seen in 20% (n=8) and 30% (n=12) subjects. There were 20 hypertensive females in the study where 30% (n=6), 20% (n=4), and 50% (n=10) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and maternal morbidity was seen in 40% (n=8) females. Diabetes was reported in 28 females where 57.14% (n=16), 14.28% (n=4), and 28.57% (n=8) subjects delivered by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery respectively and maternal morbidity was seen in 7.14% (n=2) subjects. PROM was seen in 54 subjects where 25.9% (n=14), 33.3% (n=18), and 28.57% (n=8) subjects underwent delivery by CS (cesarean section), operative vaginal delivery, and normal vaginal delivery and maternal morbidity was seen in 7.14% (n=2) study subjects. These findings were in agreement with the results of Darnal N et al⁹ in 2020 and Sanchez-Ramos L et al¹⁰ in 2024 where results for postdated pregnancies, hypertension, diabetes, and PROM comparable to the present study were also reported by the authors in their studies.

It was observed that highest induction rate of 27% was seen associated with PROM followed by 20%, 14%, 10% and 29% with postdate, diabetes, hypertension, and others. Normal vaginal delivery rates were highest with hypertension in pregnancy and polyhydramnios with 50% each followed by postdated and rhesus isoimmunization with 45% and 43% respectively. This was followed by PROM, diabetes, and IUGR with 41%, 28%, and 37% subjects respectively. In 200 subjects assessed in the study, highest cesarean section was done in fetus with IUGR and diabetes mellitus. The study results also showed that concerning 200 subjects that delivered, 50 neonates needed admission to the neonatal intensive care unit where 38 subjects were assessed for short duration and 12 subjects had low Apgar score. These results were in line with the findings of Tarimo CS et al¹¹ in 2020 and de Vaan MD et al¹² in 2023 where results for neonatal outcomes reported by the authors were similar to the results of the present study.

The results of the present study, confined within the limitations of the study, concludes that indications for induction of labor are affected greatly with the mode of delivery and also decrease the rate of emergency cesarean section and morbidity linked with it. The study outcomes were inefficient owing to a smaller sample size. Further, large randomized trials are needed to assess the impact of labor induction indication on the mode of delivery.

1. Inducing labour – clinical guideline [CG70]. National institute for health and care excellence. 2021. Available: https://www.nice.org.uk/guidance/ng207
2. James D. High Risk Pregnancy. 5th edition. Cambridge, United Kingdom: Cambridge University Press. 2018: pp.1709-18.
3. Tripathy P, Pati P, Baby P, Mohapatra SK. Prevalence and Predictors of Failed Induction. International Journal of Pharmaceutical Sciences Review And Research. 2016;39:189 - 94.
4. Soren R, Maitra N, Patel KP, Sheth T. Elective Versus Emergency Caesarean Section: Maternal complications and Neonatal Outcomes. IOSR Journal of Nursing and Health Science. 2016;5:1-4.
5. Kumar B, Kumari S, Hughes S, Savill S. Prospective cohort study of induction of labor: Indications, outcome and postpartum hemorrhage. European Journal of Midwifery. 2021;5:1-7.
6. Sharda P, Agrawal NR. Various modalities of induction of labour and its Feto-maternal outcomes: An observational study. Indian Journal of Obstetrics and Gynecology Research. 2021;8:334 - 8.
7. Beshir YM, Kure MA, Egata G, Roba KT. Outcome of induction and associated factors among induced labours in public hospitals of Harari Regional State, Eastern Ethiopia: A two years’ retrospective analysis. PLoS One. 2021;16:e0259723.
8. Kumari J, Munir A, Milner M. Impact of indication for labour induction on Caesarean Section Delivery. Obstetrics and Gynecology Research. 2021;4:101-7.
9. Darnal N, Dangal G. Maternal and fetal outcome in emergency versus elective caesarean section. Journal of Nepal Health Research Council. 2020;18:186 – 9.
10. Sanchez-Ramos L, Levine LD, Sciscione AC, Mozurkewich EL, Ramsey PS, Adair CD, Kaunitz AM, McKinney JA. Methods for the induction of labor: efficacy and safety. Am J Obstet Gynecol. 2024;230:S669–95.
11. Tarimo CS, Mahande MJ, Obure J. Prevalence and risk factors for caesarean delivery following labor induction at a tertiary hospital in North Tanzania: a retrospective cohort study (2000–2015). BMC Pregnancy Childbirth. 2020;20:173.
12. de Vaan MD, Ten Eikelder ML, Jozwiak M, Palmer KR, Davies-Tuck M, Bloemenkamp KW, Mol BWJ, Boulvain M. Mechanical methods for induction of labour. Cochrane Database Syst Rev. 2023;3:CD001233.