Incidence of cesarean delivery after induction of labor with intravenous oxytocin drip among women undergoing induction of labor at Dessie referral hospital, Northeast Ethiopia, 2017

INTRODUCTION

Induction of labor is defined as artificial stimulation of uterine contractions to cause the delivery of fetus before the onset of spontaneous labor. Labor is typically induced by using one of the following methods: cervical ripening agents, artificial rupture of membranes, and uterine stimulation with oxytocin.^1-3

Induction of labor is indicated when the benefits to either mother or fetus outweigh those of continuing the pregnancy. The World Health Organization (WHO) recommends labor induction be performed with a clear medical indication and when expected benefits outweigh potential harms. Major indications for induction of labor include post term pregnancies, pre-labor rupture of membranes, maternal medical conditions like hypertensive disorders, diabetes, renal diseases, fetal compromise, chorioamionitis, abruptio placenta, intrauterine fetal death and others. Elective induction of labour also takes place when a mother wishes to deliver at a particular time after term.^4-7

Even though labor induction had varied benefits there is a risk to the mother or fetus, this intervention may result in undesirable effect. Induction sometimes fails with potential risks of increased rate of operative vaginal delivery, caesarean birth, excessive uterine activity, abnormal fetal heart rate patterns, uterine rupture, maternal water intoxication, delivery of preterm infant due to incorrect estimation of dates, and possibly cord prolapse. Medical problems that were present before pregnancy or occurring during pregnancy may contribute to these complications.^3,8-13

The past few decades have witnessed an increase in cesarean section rate. This increase has resulted from evidence-based recommendations on how to handle certain conditions, such as fetal malposition, major placental abruption, placenta previa and prolapsed cord; however, it is mainly the consequence of a growing number of women presenting at labor with uterine scars, delivering at advanced ages, or demanding surgical delivery. Although increased frequency of obstetric interventions, induction of labor appears to have contributed to current trends in Cesarean section rates. Birth by caesarean delivery is generally more hazardous than a normal vaginal delivery, and also poses more risks for subsequent pregnancies.^6,14-16

Labor induction has been associated with increased likelihood of cesarean birth for some groups of women: first-time mothers and women whose cervix is not soft and ready to open or ripen cervix.¹⁷ In addition with controversies surrounding the use of induction with oxytocin to initiate labor and the absence of technological supports to evaluate likelihood of success in resource limited settings, there are little evidences in relation to incidence of cesarean section after induction of labor in Ethiopian hospitals. So, in this study we aimed to assess incidence of cesarean delivery after induction of labor with intravenous oxytocin drip among women undergoing labor induction at Dessie referral hospital.

METHODS

Study settings and design

A facility based cross sectional study was conducted on women undergone induction of labor during the study period of 1^st January to 30^th February 2017 GC at Dessie referral hospital, Dessie town, south east Ethiopia. Single population formula was used to calculate the sample size, by using 21.4% of the proportion of failed induction of labor. Systematic random sampling technique was used to select sample from the list of women undergone induction of labor.

Study population

All pregnant women who gave birth after 28 weeks of gestation age in Dessie referral hospital and selected as study. Mothers who gave birth after 28 weeks of gestation, singlet on with cephalic presentation were included.

Data collection methods

Data was collected from medical records of women for whom induction of labor was performed in Dessie referal hospital using pre tested structured checklist. Items were developed for this study to assess socio demography factors, obstetric factors, types of induction performed and health indication for labor induction. Checklist consist five sections that have a total of 23 items which describe the purpose of the study.

Analysis

After checking its completeness and appropriateness, the collected data was entered by EPI INFO version 3.5 and exported to SPSS version 20.0 for analysis. Different statistical analysis was undertaken. The analyzed data was presented using texts, tables, charts and graphs.

Ethical consideration

Ethical clearance letter was obtained from ethical review board of Wollo university college of health sciences. Official permission letters were also obtained from Dessie town health department and for Dessie referral hospital. Confidentiality and anonymity of the record had been ensured throughout the execution of the study by taking only the required information without using the name of the client.

RESULTS

Socio-demographic characteristics

A total 319 medical records of mothers who gave birth after induction of labor were selected for study purpose. The age of the study subjects ranged from 19-37 years and mean age and standard deviation of the selected women was 25.97 (SD=4.81) and 256 of all samples were below 30 years of age (Table1).

Obstetric condition

Most of the women 198 (62.1%) were primiparous. The mean gestational age was 37.96 weeks (range: 32-43 weeks) (Table 2). Of the included 319 women, 133 (41.7%) undergone induction of labor due to hypertensive disorder followed by 111 (34.8%) due to premature rupture of membrane (PROM) (Figure 1).

Incidence of cesarean delivery

Out of the total 170 (53.3%) of women delivered vaginally within 8 hours after induction was started, while 136 (42.6%) delivered by cesarean section (CS) (Figure 2).

IUGR: intrauterine growth retardation, IUFD: intrauterine fetal death.

From women who delivered by cesarean section 63 (19.7%) undergone CS due to failed induction of labor, 40 (12.5%) were due to fetal distress (Figure 3). From a total of 319 women sampled in 12 (3.8%) of the cases membranes were changed into meconium after induction of labor. Following induction in 15 (4.7%) of the cases fetal heart rate were recorded as non-reassuring (Table 3).

DISCUSSION

Induction of labor is one of the fastest growing procedures in current obstetric practice. The increasing incidence of induction of labor may be attributed to multiple possible causes. Increasing trends of maternal morbidity, which as previously discussed may increase the number of medical indications for IOL, are one possible cause. However, the fact that higher remunerative payers are associated with higher rates of IOL suggests that nonclinical factors such as provider or patient preference may also play a role. The World Health Organization and the American college of nurse-midwives (ACNM) both advocate that IOL should only be performed when there is a clear medical indication supported in the literature and the benefits outweigh the potential harms.in addition to that Labor induction has been associated with increased likelihood of cesarean birth for some groups of women like primigrava mother and those mothers and women whose cervix is not soft and ready to open or ripen cervix.

The present study showed that mode of delivery was Normal Vaginal delivery 53.3%, cesarean delivery 42.6% and 4.1% via instrumental delivery. This finding is in line with cesarean section rate in the study conducted at Dessie town hospitals.¹⁸

The main indication of induction in this study were hypertension during pregnancy following pre labor rupture of membrane, intrauterine fetal death, post term pregnancy and intrauterine growth retardation. Similarly, the study done in Kathmandu Medical College Teaching Hospital showed predominant indications for induction were: post term pregnancy, PROM, oligohydramnious, and others. In the study done at a regional hospital in KwaZulu-Natal, South Africa the three main indications for induction of labor were hypertensive disorders, post-dates pregnancy and pre-labour rupture of the membranes.⁴ However, the study done Hawassa public health facilities showed predominant indications for induction were: premature rapture of membrane, preeclampsia, post term and chorioamnionitis. In the study done at Jimma University specialized hospital the three main indications for induction of labor were premature rupture of membrane, hypertension disorder and post-term.^12,13

The main indications for cesarean delivery in this study were failed induction of labor followed by fetal distress, cephalo pelvic disproportion and malposition. Similar indication also reported by Mehta et al, Calder et al, Wilson et al and Macer et al, but Abdulkadir revealed that post term pregnancy the leading indications for cesarean delivery.^7,16,17

CONCLUSION

In this study incidence of cesarean delivery after induction of labor with oxytocin infusion was 42.6%. The main indications for induction of labor were hypertension during pregnancy, pre labor rupture of membrane, intrauterine fetal death, post term pregnancy and intrauterine growth retardation. The main indications for cesarean delivery in this study were failed induction of labor, fetal distress, cephalo pelvic disproportion and malposition.

Data availability

The datasets generated and/or analyzed during the current study are not publicly available due to some privacy reasons but are available from the corresponding author on reasonable request.

ACKNOWLEDGEMENTS

I would also like to express my deepest gratitude for Dessie Referral Hospital management and staffs for their cooperation. I would also like to thank Wollo University, College of Medicine and Health Sciences, school of department of nursing and midwifery and department of midwifery for financial support.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: The study was approved by the institutional ethics committee

REFERENCES

1. 1. Bonsack CF, Lathrop A, Blackburn M. Induction of labor: update and review. J Midwifery Womens Health. 2014;59(6):606-15.
2. 2. Lopezosa HP, Maestre HM, Borrego RMA. Labor stimulation with oxytocin: effects on obstetrical and neonatal outcomes. Rev Lat Am Enfermagem. 2016;24:2744.
3. 3. Hussain AA, Yakoob MY, Imdad A, Bhutta ZA. Elective induction for pregnancies at or beyond 41 weeks of gestation and its impact on stillbirths: a systematic review with meta-analysis. BMC Public Health. 2011;11(3):5.
4. 4. Lawani OL, Onyebuchi AK, Iyoke CA, Okafo CN, Ajah LO. Obstetric outcome and significance of labour induction in a health resource poor setting. Obstet Gynecol Int. 2014;2014:419621.
5. 5. Levine LD, Elovitz MA, Limaye M, Sammel MD, Srinivas SK. Induction, labor length and mode of delivery: the impact on preeclampsia-related adverse maternal outcomes. J Perinatol. 2016;36(9):713-7.
6. 6. Mozurkewich EL, Chilimigras JL, Berman DR, Perni UC, Romero VC, King VJ, et al. Methods of induction of labour: a systematic review. BMC Pregnancy Childbirth. 2011;11:84.
7. 7. Sinkey RG, Lacevic J, Reljic T, Hozo I, Gibson KS, Odibo AO, et al. Elective induction of labor at 39 weeks among nulliparous women: The impact on maternal and neonatal risk. PLoS One. 2018;13(4):0193169.
8. 8. Banos N, Migliorelli F, Posadas E, Ferreri J, Palacio M. Definition of Failed Induction of Labor and Its Predictive Factors: Two Unsolved Issues of an Everyday Clinical Situation. Fetal Diagn Ther. 2015;38(3):161-9.
9. 9. Caughey AB. Induction of labour: does it increase the risk of cesarean delivery. BJOG. 2014;121(6):658-61.
10. 10. Davey MA, King J. Caesarean section following induction of labour in uncomplicated first births- a population-based cross-sectional analysis of 42,950 births. BMC Pregnancy Childbirth. 2016;16:92.
11. 11. Dunn L, Kumar S, Beckmann M. Maternal age is a risk factor for caesarean section following induction of labour. Aust NZ J Obstet Gynaecol. 2017;57(4):426-31.
12. 12. Girma W, Tseadu F, Wolde M. Outcome of Induction and Associated Factors among Term and Post-Term Mothers Managed at Jimma University Specialized Hospital: A Two Years’ Retrospective Analysis. Ethiopian J Health Sci. 2016;26(2):121.
13. 13. Hurissa BF, Belachew TMG. Prevalence of Failed Induction of Labor and Associated Factors Among Women Delivered in Hawassa Public Health Facilities, Ethiopia, 2015. J Womens Health Care. 2015;04(05):1-6.
14. 14. Mhaske N, Agarwal R, Wadhwa RD, Basannar DR. Study of the Risk Factors for Cesarean Delivery in Induced Labors at Term. J Obstet Gynaecol India. 2015;65(4):236-40.
15. 15. Stoll KH, Hauck YL, Downe S, Payne D, Hall WA, International Childbirth Attitudes - Prior to Pregnancy Study T. Preference for cesarean section in young nulligravid women in eight OECD countries and implications for reproductive health education. Reprod Health. 2017;14(1):116.
16. 16. Tolcher MC, Holbert MR, Weaver AL, McGree ME, Olson JE, El-Nashar SA, et al. Predicting Cesarean Delivery After Induction of Labor Among Nulliparous Women at Term. Obstet Gynecol. 2015;126(5):1059-68.
17. 17. Zhao Y, Flatley C, Kumar S. Intrapartum intervention rates and perinatal outcomes following induction of labour compared to expectant management at term from an Australian perinatal centre. Aust NZ J Obstet Gynaecol. 2017;57(1):40-8.
18. 18. Wondie AG, Zeleke AA, Yenus H, Tessema GA. Cesarean delivery among women who gave birth in Dessie town hospitals, Northeast Ethiopia. PloS one. 2019;14(5):0216344.