Risk of cesarean section after induced versus spontaneous labor at term gestation

Maternal and Perinatal Outcome After Induction of Labor Versus Expectant Management in Low-risk Pregnancies Beyond Term

BACKGROUND/AIM

Due to still controversial discussion regarding appropriate termination of low-risk singleton pregnancies beyond term, this retrospective study aimed to evaluate maternal and perinatal outcomes depending on gestational age and obstetric management.

PATIENTS AND METHODS

This is a retrospective cohort analysis including 3.242 low-risk singleton deliveries at the Department of Obstetrics of the University Hospital of Cologne between 2017 and 2022. According to current national guidelines, the cohort was subdivided into three gestational groups, group 1: 40+0-40+6 weeks, group 2: 40+7-40+10 weeks and group 3>40+10 weeks.

RESULTS

In our cohort, advanced gestational age was associated with higher rates of secondary caesarean sections, lower rates of spontaneous vaginal deliveries, higher rates of meconium-stained amniotic fluid and depressed neonates with APGAR < 7 after 5 min. Analyzing obstetric management, induction of labor significantly increased the rate of secondary sections and reduced the rate of spontaneous deliveries, while the percentage of assistant vaginal deliveries was independent from obstetric management and gestational age. Induction of labor also significantly enhanced the need for tocolytic subpartu and epidural anesthesia and caused higher rates of abnormalities in cardiotocography (CTG), which also resulted in more frequent fetal scalp blood testing; however, the rate of fetal acidosis was independent of both obstetric management and gestational age.

CONCLUSION

Our study supports expectant management of low-risk pregnancies beyond term, as induction of labor increased the rate of secondary sections and did not improve perinatal outcome.

Predictors of Induction of Labor and Success Rate Among Mothers Giving Birth at Jimma University Medical Centre South West Ethiopia: Unmatched Case Control Study

BACKGROUND

Induction of labor is defined as the process of artificially stimulating the uterus to start labor. Despite the unquestionable reputation of labor induction for ending pregnancies, there is a risk to the mother and/or the fetus. Studies from developed and developing countries report increased labor induction rates with additional cases of cesarean section (CS) and fetal distress.

OBJECTIVE

The main aim of this study is to assess predictors of induction of labor and the success rate among mothers giving birth at Jimma University Medical Centre Southwest Ethiopia.

METHODS

A facility based unmatched case control quantitative study design was done among 694 (cases = 347 plus controls is 347) mothers. A systematic random sampling technique was used to select both cases and controls from the registration delivery log book. A standard document review checklist was used to collect data. Multivariate binary logistic regression analysis was done to identify predictors of the outcome of the variable.

RESULTS

The study findings revealed that the success rate of induction of labor in this study was 73.8%. Mothers with stillbirth history were three times more likely to be induced compared with mothers without stillbirth history. Mothers with abortion history were seven times more likely to be induced than mothers without an abortion history. Mothers with a gestational age of ≥42 weeks were 17 times more likely to be induced than mothers with a gestational age of 38–41 weeks. Mothers who had no antenatal care follow-up were seven times more likely to be induced than mothers who had antenatal care follow-up.

CONCLUSION

Maternal age, gestational age, history of abortion, and history of stillbirth were significant predictors of induction of labor which was claimed to increase the rate of uterine rupture, CS and admission to a neonatal intensive care unit (NICU).

Critical Evaluation of Clinical Research in Obstetrics and Gynecology

Within the evolving field of obstetrics and gynecology, providers should possess the ability to effectively and critically evaluate medical literature in order to best adapt and incorporate evidence-based practice. For both clinicians and researchers alike, we provide a systematic approach for reviewing a journal article published in the medical literature. We summarize the various types of study designs, with dedicated attention to observational and experimental studies, and examine sources of bias inherent to these study designs. Finally, we review important considerations when interpreting the validity and significance of the results and conclusions of a research study.

Failed induction of labor and associated factors among women undergoing induction at University of Gondar Specialized Hospital, Northwest Ethiopia

BACKGROUND

Induction of labor is a process of artificially initiating labor to attain vaginal birth. Despite its vital role in the reduction of maternal mortality, the failure rate of induction and its contributing factors were not well studied in Ethiopia; particularly there was a limited study in the study area. This study aimed to assess the prevalence and factors associated with failed induction of labor among women undergoing induction at University of Gondar Specialized Hospital, Northwest Ethiopia.

METHODS

An institution-based retrospective cross-sectional study was conducted among 743 women undergoing induction at University of Gondar Specialized Hospital. A systematic random sampling method was used to draw a sample and the data were retrieved from the maternity registration books and medical records. Data were cleaned and entered into EpiData version 3.1 and SPSS version 20 used for analysis. Frequencies, proportions, and summary statistics were used to describe the study population and a multivariable logistic regression model was fitted to identify factors contributing to failed induction of labor. Odds ratio with 95% confidence interval computed and level of significance declared at P-value< 5%.

RESULTS

The prevalence of failed induction of labor was 24.4% (95% CI: 21.4, 27.9). Age ≤ 30 years (AOR = 3.7, 95% CI: 2.2,6.2), rural residence (AOR = 3.7, 95% CI: 2.4,5.8), being nulliparous (AOR = 2.1, 95% CI: 1.2,3.7), 5 or less Bishop Score (AOR = 3.4, 95% CI: 2.2,5.4), premature rupture of membrane (AOR = 2.7, 95% CI: 1.5,4.6), having pregnancy-induced hypertension (AOR = 4.0, 95% CI: 2.3,7.1), and artificial rupture of membrane with oxytocin (AOR = 0.2, 95% CI: 0.1, 0.4) were associated with failed induction of labor.

CONCLUSIONS

One-fourth of women undergoing induction at University of Gondar Specialized Hospital had failed induction of labor. Age, residence, parity, bishop score, premature-rupture of the membrane, pregnancy-induced hypertension, and method of induction were independent predictors for failed induction of labor. The combination method of ARM with oxytocin, early detection and treatment of pregnancy-induced hypertension and premature rupture of the membrane are highly recommended for reducing failed induction of labor.

Proportion and Outcome of Induction of Labor Among Mothers Who Delivered in Teaching Hospital, Southwest Ethiopia

Background: Despite the induction of labor (IOL) having had some undesired consequences, it also has several benefits for maternal and perinatal outcomes. This study aimed to assess the proportion and outcome of IOL among mothers who delivered in Teaching Hospital, southwest Ethiopia.

Methods: A retrospective cross-sectional study was conducted from June 10 to June 20, 2019, among 294 mothers who gave birth between November 30, 2018, and May 30, 2019, by reviewing their cards using a structured checklist to assess the prevalence, outcome, and consequences of induction of labor. A binary logistic regression analysis was computed to look for the association between outcome variables and independent variables.

Results: The prevalence of labor induction was 20.4%. The most commonly reported cause of induction was preeclampsia (41.6%). The factors associated with IOL were mothers aged 25–34 years [AOR = 2.55, 95% CI (1.18–5.50)] and ≥35 years [AOR = 10.6, 95% CI (4.20–26.9)], having no history of antenatal care [AOR = 2.12, 95% CI (1.10–4.07)], and being Primipara AOR = 2.33, 95% CI (1.18–3.24)]. Of the 60 induced mothers, 23.3% had failed induction. The proportion of mothers with dead fetal outcomes and maternal complications was 5 and 41.7%, respectively. The unfavorable Bishop Score before induction [AOR = 1.85, 95% CI (1.32–4.87)] and induction using misoprostol [AOR = 1.48, 95% CI (1.24–5.23)] were the factors associated with failed induction of labor.

Conclusion: The prevalence of induced labor was considerably higher than rates in other Ethiopian studies; however, the prevalence of induction failure was comparable to other studies done in Ethiopia. The study found that Bishop's unfavorable score before induction and induction using misoprostol was the factor associated with unsuccessful induction. Therefore, the health professionals should confirm the favorability of the cervical status before the IOL to increase the success rate of induction of labor.

Degree of intrapartum fever and associated factors: Three group analysis of no fever, borderline and overt fever

AIM

Previous studies analyzing intrapartum fever by dichotomization of fever just above 38.0°C or not may lead to overlook clinical significance of borderline fever. We aimed to investigate the maternal baseline and intrapartum characteristics, neonatal outcomes, and inflammatory placental pathology in relation to the degree of intrapartum fever by three group analysis.

METHODS

We performed a retrospective analysis of consecutive singleton deliveries between 37^0/7 to 41^0/7 weeks divided into three groups based on the peak body temperature during labor: No fever (< 37.5°C), borderline fever (≥ 37.5°C and < 38.0°C), and overt fever (≥ 38.0°C). Maternal and intrapartum characteristics, neonatal outcomes, and inflammatory placental pathology were compared by trend analysis, intergroup difference analysis, and multivariable analysis.

RESULTS

The degree of intrapartum fever was significantly associated with younger maternal age, nulliparity, longer duration of rupture of membrane, and epidural analgesia (p < 0.001). And the incidence of neonatal proven sepsis and mortality were not significantly different among the groups. The degree of intrapartum fever was associated with the stage of acute chorioamnionitis and funisitis (p < 0.001). Multivariate analysis revealed that the association with epidural analgesia was stronger in borderline fever than overt fever (adjusted odds ratio [95% confidence interval], borderline fever = 18.487 [11.447-29.857]; overt fever = 11.068 [4.874-25.133]) after controlling for maternal age, parity, induction or augmentation, duration of ROM, birth weight, and meconium staining.

CONCLUSION

Our data support that both epidural analgesia and inflammation of the placenta may contribute to the development of intrapartum fever at term.

Rate of intrapartum cesarean section and related factors in older nulliparous women at term

AIM

The aim of this study was to determine the effect of maternal age on emergency cesarean section (CS) during labor, and to identify the independent risk factors for emergency CS.

METHODS

This was a retrospective cohort study using data from 2009 to 2014 from a tertiary perinatal care center in Japan. Inclusion criteria were maternal age ≥ 35 years, nulliparous singleton pregnancy at term and a cephalic presentation without indication of elective CS at onset of labor. The primary outcome was rate of emergency CS, while independent risk factors were elucidated using multivariate logistic regression analysis.

RESULTS

Of 953 women, 199 (20.9%) delivered by emergency CS. Rates of emergency CS were 18.3% (129/706) in women aged 35-39 years and 28.3% (70/247) in those aged ≥ 40 years (P < 0.01). Adjusted odds ratios (95% confidence intervals) of independent risk factors were 1.50 (1.03-2.18) for maternal age ≥ 40 years, 1.51 (1.06-2.17) for body mass index ≥ 25 kg/m² , 2.22 (1.24-3.98) for hypertensive disorder during pregnancy, 3.43 (1.31-8.95) for large-for-date fetus and 4.64 (3.23-6.69) for induction of labor.

CONCLUSIONS

The rate of intrapartum emergency CS in older nulliparous women at term was approximately 21%. Induction of labor should be recognized as a significant factor for emergency CS.

Is the Bishop-score significant in predicting the success of labor induction in multiparous women?

OBJECTIVE

To determine whether the Bishop-score upon admission effects mode of delivery, maternal or neonatal outcomes of labor induction in multiparous women.

STUDY DESIGN

A retrospective study including 600 multiparous women with a singleton pregnancy, 34 gestational weeks and above who underwent labor induction for maternal, fetal or combined indications. Induction was performed with one of three methods- oxytocin, a slow release vaginal prostaglandin E2 insert (10 mg dinoprostone) or a transcervical double balloon catheter. The women were divided into two groups-Bishop-score <6 and Bishop-score ⩾6. We evaluated labor course, maternal complications (postpartum hemorrhage, manual lysis, uterine revision, perineal tear grade 3-4, need for blood transfusions, relaparotomy, prolonged hospitalization) and neonatal outcomes (Apgar score, cord pH, hospitalization in the neonatal intensive care unit, prolonged hospitalization).

RESULTS

Both groups had a high rate of vaginal deliveries-93.7% and 94.9%, respectively. There was no difference between the two groups in terms of maternal or neonatal outcomes.

CONCLUSION

Labor induction in multiparous women is safe and successful regardless of the initial Bishop-score. In multiparous women the Bishop-score is not a good predictor for the success of labor induction, nor is it a predictor for maternal of neonatal adverse outcomes and complications.

Small-for-gestational-age babies of low-risk term pregnancies: does antenatal detection matter?

OBJECTIVES

To compare delivery route and admission rate to neonatal intensive care unit between small- and appropriate-for-gestational-age babies among low-risk term pregnancies.

METHODS

A retrospective study was conducted using the database of deliveries in 2014 at a tertiary hospital. Babies delivered at ≥37 weeks with birthweight <10th centile were considered small-for-gestational-age (SGA) and >90th centile were considered large-for-gestational-age. Fetal weight estimation at 30-33 weeks ultrasound <10th centile was considered antenatal detection of SGA.

RESULTS

Among 1429 low-risk term pregnancies, 11% (151/1429) had SGA babies and 5% (75/1429) had large-for-gestational-age. SGA babies were associated with higher rate of cesarean sections for nonreassuring fetal status (18/151 versus 8/1202, p < .001) and higher rate of admissions to neonatal intensive care unit (16/151 versus 18/1202, p < .001) compared to appropriate-for-gestational-age. Within SGA group, antepartum detected fetuses were associated with lower rate of operative deliveries for nonreassuring fetal status than undetected group (3/31 versus 39/120, p = .01) Conclusions: In our series, women with SGA term babies were associated with more adverse obstetric and neonatal outcome than appropriate-for-gestational age, especially among those undetected prenatally.

Predicting factors for success of vaginal delivery in preterm induction with prostaglandin E2

Objective

To evaluate the efficacy and safety of prostaglandin (PG) E₂ for preterm labor induction and to investigate the predictive factors for the success of vaginal delivery.

Methods

A retrospective cohort study was performed in women (n=155) at 24+0 to 36+6 weeks of gestation who underwent induction of labor using a PGE₂ vaginal pessary (10 mg, Propess) from January 2009 to December 2015. Success rates of vaginal delivery according to gestational age at induction and incidence of intrapartum complications such as tachysystole and nonreassuring fetal heart rate were investigated. Multivariable logistic regression analysis was performed to evaluate the predictive factors for success of labor induction.

Results

The vaginal delivery rate was 57% (n=89) and the rate of cesarean delivery after induction was 43% (n=66). According to gestational age, labor induction was successful in 16.7%, 50.0%, and 62.8% of patients at 24 to 31, 32 to 33, and 34 to 36 weeks, showing a stepwise increase (P=0.006). There were 18 cases (11%) of fetal distress, 9 cases (5.8%) of tachysystole, and 6 cases (3.8%) of massive postpartum bleeding (>1,000 mL). After adjusting for confounding factors, multiparity (odds ratio [OR], 8.47; 95% confidence interval [CI], 3.10 to 23.14), younger maternal age (OR, 0.84; 95% CI, 0.75 to 0.94), advanced gestational age at induction (OR, 1.06; 95% CI, 1.02 to 1.09), rupture of membranes (OR, 11.83; 95% CI, 3.55 to 39.40), and the Bishop score change after removal of PGE₂ (OR, 2.19; 95% CI, 1.0 to 4.8) were significant predictors of successful preterm vaginal delivery.

Conclusion

An understanding of the principal predictive factors of successful preterm labor induction, as well as the safety of PGE₂, will provide useful information when clinicians consult with preterm pregnant women requiring premature delivery.

Why do multiparous women with a history of vaginal delivery give birth by cesarean section?

OBJECTIVE

A cesarean section (C-section) is performed to deliver a baby through the mother's abdomen. In recent years, the rate of incidences requiring a C-section is steadily increasing all over the world. Advanced maternal age, chronic health problems, multiple pregnancies as a result of the development of assisted reproductive technologies, and an insufficient supplementary health network can be considered as the reasons why mothers and obstetricians prefer a C-section. Our study aimed to identify the risk factors for the need of C-section in women with a history of vaginal delivery.

MATERIAL AND METHODS

238 multiparous women with a history of vaginal birth at 37-42 gestational weeks were enrolled in our study. 110 women had underwent C-section. Control group was chosen randomly from women giving birth by vaginal route.

RESULTS

Overall, 238 multiparous women with a history of vaginal delivery at 37-42 gestational weeks were enrolled in our study. The history of operative delivery, that of labor induction and presence of meconium and the indication of admission to the delivery room were different between groups. A lower Bishop score and biophysical profile, smaller gestational period, and lower birth weight were associated with the group requiring a C-section, whereas older age and a long time interval from the previous birth were associated with the group not requiring a C-section.

CONCLUSION

A strategy involving either labor induction or not could be individualized for each patient to eliminate the risk factors for adverse outcomes. To identify criteria for the standardization of labor management, further studies are needed.