Induction of labour in patients with prior caesarean births or uterine surgery

The current evidence favours trial of labour after one caesarean in the absence of any other contraindications, recognizing that risks with both trial of labour after caesarean (TOLAC) and elective repeat caesarean section (ERCS) birth are relatively uncommon. When the need for induction of labour (IOL) following a previous caesarean arises, shared decision-making should be based on the current available evidence. This approach, however, needs to be tailored, taking into account the individual's history, initial examination and response to the ongoing process of induction to optimize the maternal and foetal outcomes. This paper aims to review the evidence and provide guidance on decision making surrounding labour induction in a pregnancy following a prior caesarean or uterine surgery.     

Prediction of a caesarean delivery by labour and delivery nurses

The predictive accuracy of a nurse on labour and delivery to foretell the route of delivery is unknown. Registered nurses directly involved in managing women's labour predicted the route of delivery on 199 women between September 2005 and September 2006. The sensitivity to identify women who subsequently would deliver by caesarean was 26% (95% CI 13-42%); positive predictive value of 38% (20-39%) and likelihood ratio of 2.6 (1.3-7.5). Experience did not improve the predictive accuracy.     

Pharmacological induction of labour: benefits and risks

AIM: Induction of labour is a very common practice in modern obstetrics. The most used method is based on the use of topical prostaglandins. In this study we aimed to analyse the results of pharmacological induction of labour through the use of dinoprostone, comparing the intracervical gel (Prepidil 0.5 mg) and the vaginal insert (Propess 10 mg). METHODS: An observational longitudinal study was conducted, in which all patients treated with prostaglandins from January 1, 2003 to June 30, 2006 were included, for a total of 852 cases. The intracervical gel was applied on 32.5% of pregnant women (277 patients) while the vaginal insert to 56.2% (479 patients); in 11.3% of the cases (96 patients) both preparations were administered, one after the other. RESULTS: In 2/3 of the total (568 patients), the induction led to vaginal delivery, in contrast to 284 cases in which the practice showed negative results: in 270 women (31.7%) a cesarean section was practiced. Adverse events occurred only in 1.8% of cases (16 patients); the most frequent adverse reaction was uterine hypertonus in 1.8% of cases, which was in any case resolved with removal of the vaginal insert or injection of a tocolytic drug (atosiban). CONCLUSION: Induction through prostaglandins is an effective and safe method to get cervical maturation. Its success is influenced by Bishop score. In the case of unfit cervix, vaginal insert seems to get better results than intracervical gel. The relation between risks and benefits is certainly better in the latter.     

Maternal height and prior vaginal delivery as predictive factors in trial of labour after one caesarean section.

A retrospective study of 304 booked parturients with one previous lower segment caesarean section for non-recurrent indications was carried out with regards to factors predicting successful trial of vaginal delivery. The height of the parturients, as well as a history of a previous vaginal delivery appeared to be predictive factors of success. Seventy per cent of the parturients succeeded in delivering vaginally. The mean fetal birthweight was 3362 g for women with vaginal delivery, while the mean maternal height was 1.58 m. Of those who needed a repeat caesarean section, surgical intervention in 46.15% of the patients was indicated by poor cervicometric progress, which might have been appropriately addressed by oxytocin augmentation and careful monitoring in labour. Regarding prior vaginal delivery, only 31.1% of parturients with a negative history, but 63.15% with a positive history, had a successful trial. Three cases of ruptured uterus were all the result of unacceptable delay in carrying out an abdominal delivery when it was clearly indicated. A large prospective study into this aspect of obstetric care will probably define additive effects of these two definite factors.     

Delayed second twin delivery: benefits and risks

Background: An increasing number of reports describe the delayed second twin delivery for days, or weeks with good results in the majority of the cases, and different survival rate between centers, without reported randomized controlled trials (RCTs).

Objectives: This study was designed to evaluate the suggested management of the delayed second twin delivery in the Sabah Maternity Hospital regarding its outcome, possible risks, and benefits.

Patients and methods: Forty-seven twin pregnancies with preterm labor (PTL) of the first fetus between 20–30 weeks, and delayed delivery of the second twin were included in this study. Studied women signed informed consent about the possible risks of keeping the live fetus in the hostile intrauterine environment, and benefits of the prolonged gestation for the second twin. Throughout the conservative treatment of the second twin, the studied women were hospitalized with regular follow up for infections, consumptive coagulopathy parameters, and wellbeing of the second twin.

Results: There was significant difference in the gestational age at delivery between the first and second twin (22.6?±?3.4 versus 34.3?±?2.5 weeks; respectively, p?=?.01). There was significant difference in the birth weight between the first and second twin (435?±?91.2 versus 1472?±?61.5?g; respectively, p?=?.004). The rate of the cesarean delivery was significantly high during delivery of the second twin compared with the first twin (23.4% (11/47) versus 0% (0/47); respectively, p?=?.0001) with high survival rate for the second twin (85.1% (40/47)) after the delayed second twin delivery.

Conclusions: The birth weight, the gestational age, and the survival rate of the studied second twin significantly increased after the suggested management of the delayed second twin delivery.     

Maternal and perinatal morbidity of caesarean delivery at full cervical dilatation compared with caesarean delivery in the first stage of labour

To estimate maternal and perinatal morbidity associated with caesarean delivery at full cervical dilatation, a population-based cohort study from 1997 to 2002 was used, which included 1623 nullipara with singleton pregnancies at 37-42 weeks of gestation requiring caesarean delivery in labour. Compared to caesarean delivery at less than full dilatation, women undergoing caesarean delivery at full dilatation were more likely to have complications of intraoperative trauma (RR 2.6, P < 0.001) and infants with perinatal asphyxia (RR 1.5, P < 0.05). There was no difference in maternal or perinatal morbidity when duration of the second stage of labour or when failed assisted vaginal delivery was considered.     

Methods of induction of labour: a systematic review

Background

Rates of labour induction are increasing. We conducted this systematic review to assess the evidence supporting use of each method of labour induction.

Methods

We listed methods of labour induction then reviewed the evidence supporting each. We searched MEDLINE and the Cochrane Library between 1980 and November 2010 using multiple terms and combinations, including labor, induced/or induction of labor, prostaglandin or prostaglandins, misoprostol, Cytotec, 16,16,-dimethylprostaglandin E2 or E2, dinoprostone; Prepidil, Cervidil, Dinoprost, Carboprost or hemabate; prostin, oxytocin, misoprostol, membrane sweeping or membrane stripping, amniotomy, balloon catheter or Foley catheter, hygroscopic dilators, laminaria, dilapan, saline injection, nipple stimulation, intercourse, acupuncture, castor oil, herbs. We performed a best evidence review of the literature supporting each method. We identified 2048 abstracts and reviewed 283 full text articles. We preferentially included high quality systematic reviews or large randomised trials. Where no such studies existed, we included the best evidence available from smaller randomised or quasi-randomised trials.

Results

We included 46 full text articles. We assigned a quality rating to each included article and a strength of evidence rating to each body of literature. Prostaglandin E2 (PGE2) and vaginal misoprostol were more effective than oxytocin in bringing about vaginal delivery within 24 hours but were associated with more uterine hyperstimulation. Mechanical methods reduced uterine hyperstimulation compared with PGE2 and misoprostol, but increased maternal and neonatal infectious morbidity compared with other methods. Membrane sweeping reduced post-term gestations. Most included studies were too small to evaluate risk for rare adverse outcomes.

Conclusions

Research is needed to determine benefits and harms of many induction methods.     

Misoprostol for induction of labour: a systematic review.

OBJECTIVE: To determine, from the best available evidence, the effectiveness and safety of misoprostol administered vaginally or orally for third trimester cervical ripening or induction of labour. METHODS: Clinical trials of misoprostol used for cervical ripening or labour induction in the third trimester were identified from the register of randomised trials maintained by the Cochrane Pregnancy and Childbirth Group. All identified trials were considered for inclusion in the review according to a prespecified protocol. Primary outcomes were chosen to address clinical effectiveness (delivery within 24 hours) and safety (uterine hyperstimulation, caesarean section, serious maternal and neonatal morbidity) and were determined a priori. All meta-analyses were based on the intention-to-treat principle. In the absence of heterogeneity the summary statistics have been expressed as typical relative risk (RR) and 95% confidence interval (CI). RESULTS: Vaginal misoprostol: one small study showed that the use of misoprostol results in more effective cervical ripening and reduced need for oxytocin when compared with placebo. When compared with oxytocin, vaginal misoprostol was more effective for labour induction. The relative risk of failure to achieve vaginal delivery within 24 hours was 0.48 (95% CI 0.35 to 0.66). However, the relative risks for uterine hyperstimulation with and without fetal heart rate abnormalities were 2.54 (95% CI 1.12 to 5.77) and 2.96 (95% CI 2.11 to 4.14), respectively. In three out of four trials which studied women with intact membranes and unfavourable cervices, failure to achieve vaginal delivery within 24 hours was reduced with misoprostol when compared with other prostaglandins (RR 0.71, 95% CI 0.62 to 0.81). Vaginal misoprostol was associated with increased uterine hyperstimulation both without fetal heart rate changes (RR 1.67, 95% CI 1.30 to 2.14) and with associated fetal heart rate changes (RR 1.45, 95% CI 1.04 to 2.04). There was also an increase in meconium stained amniotic fluid following vaginal misoprostol (RR 1.38, 95% CI 1.06 to 1.79). Oral misoprostol: one small trial suggests that, when compared with placebo, oral misoprostol reduces the need for oxytocin and shortens the time between induction and delivery. Compared with other prostaglandins one small trial showed a reduced need for oxytocin with oral misoprostol. Two trials compared oral with vaginal misoprostol using different doses. No significant differences were evident. CONCLUSIONS: Overall, misoprostol appears to be more effective than conventional methods of cervical ripening and labour induction. Although no differences in perinatal outcome were shown, the studies were not sufficiently large to exclude the possibility of uncommon serious adverse effects. In particular the increase in uterine hyperstimulation with fetal heart rate changes following misoprostol is a matter for concern. It is possible that, if sufficient numbers are studied, an unacceptably high number of serious adverse events including uterine rupture and asphyxial fetal deaths may occur. The data at present are not robust enough to address the issue of safety. Thus, though misoprostol shows promise as a highly effective, inexpensive and convenient agent for labour induction, it cannot be recommended for routine use at this stage. Lower dose misoprostol regimens should be investigated further.     

Transcutaneous electrical nerve stimulation in labour pain: a systematic review

Objective To review the effectiveness and safety of transcutaneous electrical nerve stimulation (TENS) for labour pain.
Design A systematic review of randomised controlled trials of TENS in pain during labour.
Sample Eight reports involving 712 women were included; 352 women received active TENS and 360 acted as controls.
Methods Reports were sought by searching MEDLINE and the Oxford Pain Relief Database.
Main outcome measures Analgesic and adverse effect outcomes.
Results Evidence for reduced pain using TENS in labour was weak. Additional analgesic interventions may be less likely with TENS (odds ratio 0.57; 95% CI 0.34–0.96), number-needed-to-treat 14 (95% CI 7.3–119).
Conclusions Randomised controlled trials provide no compelling evidence for TENS having any analgesic effect during labour. Weak positive effects in secondary (analgesic sparing) and tertiary (choosing TENS for future labours) outcomes may be due to inadequate blinding causing overestimation of treatment effects.     

Uterine rupture and risk factors for caesarean delivery following induced labour in women with one previous lower segment caesarean section

Objective: To determine the outcome of induction of labor, specifically incidence of uterine rupture and reliable predictors of repeat caesarean delivery, in women undergoing induction of labor after previous caesarean section. Methods: A review of obstetric and perinatal records of 167 women who had their labor induced after one transverse lower uterine incision performed at previous caesarean delivery in a referral tertiary hospital in Nigeria between January 2006 and December 2009. Results: The incidence of uterine rupture was 2.4%. Independent risk factors for repeat caesarean delivery were absence of prior vaginal delivery (OR 3.7; 95% CI 1.9–7.1), duration of latent phase >2?h (OR 4.3; 95% CI 1.7–11.2), postdated pregnancy (OR 2.2; 95% CI 1.1–4.0) and previous caesarean for non-recurrent indication (OR 2.1; 95% CI 1.1–4.0). Conclusion: Choice of appropriate delivery option for this cohort of women based on the identified risk factors is essential to minimize the incidence of failed vaginal birth and its associated adverse maternal and neonatal outcome.     

Benefits of vaginal misoprostol prior to IUD insertion in women with previous caesarean delivery: a randomised controlled trial

Objective: The aim of the study was to evaluate the value of vaginal misoprostol 6?h prior to intrauterine device (IUD) insertion in women with previous Caesarean delivery.

Methods: A double-blind randomised controlled trial was conducted in 120 women who were eligible for IUD insertion. Participants were randomly divided to receive either 600?μg vaginal misoprostol or placebo 6?h before IUD insertion. The primary outcome measure was the pain score during the procedure. Secondary outcome measures were failure of insertion, insertion difficulty score, complications of IUD insertion and side effects related to misoprostol.

Results: Pain and insertion difficulty scores were significantly lower in the misoprostol group compared with the placebo group (5.7?±?1.4 vs. 6.5?±?0.9 and 4.1?±?1.1 vs. 5.4?±?2.2, respectively; p?p?=?.06) and cramps (10 vs. 0; p?Conclusions: The use of misoprostol before IUD insertion is associated with less painful and easier placement.     

The Bishop Score as a determinant of labour induction success: a systematic review and meta-analysis

Purpose

To evaluate the association between the Bishop Score and successful induction.

Study strategy and selection criteria

We searched the PubMed and the lists of references of relevant studies to identify reports on the association between Bishop Score and achieving active phase of labour or vaginal delivery.

Data collection and analysis

We abstracted crude or adjusted measures of association from studies. Summary odds ratio (OR) and summary hazard ratio (HR), and 95?% confidence interval (95?% CI) were obtained by random effects meta-analysis. Study heterogeneity was assessed using the I ² test.

Results

Fifty-nine studies met the inclusion criteria. Analyses with crude ORs showed that women with higher versus lower Bishop Score were more likely to achieve vaginal delivery either with no time limit for this to occur, or within a certain time interval; the summary ORs according to the Bishop Score cutoff ranged from 1.98 (95?% CI: 1.58?C2.48; I ²?=?36.6?%) to 5.48 (95?% CI: 1.67?C17.96; I ²?=?0.0?%) and from 2.15 (95?% CI: 1.36?C3.40; I ²?=?0.0?%) to 4.22 (95?% CI: 2.48?C7.17; I ²?=?11.0?%), respectively. Summary estimates per unit increase in the Bishop Score, based on adjusted ORs, showed a positive association with achieving vaginal delivery, either with no time limit (OR_summary?=?1.33; 95?% CI: 1.13?C1.56; I ²?=?66.1?%) or within a certain time interval (OR_summary?=?1.52; 95?% CI: 1.37?C1.70; I ²?=?42.4?%). Summary HRs per unit increase in Bishop Score showed an association with induction to vaginal delivery (HR_summary?=?1.28; 95?% CI: 1.21?C1.36; I ²?=?0.0?%), but not with induction to active phase (HR_summary?=?1.21; 95?% CI: 0.88?C1.68; I ²?=?70.7?%) time interval.

Conclusions

Bishop Score seems be a determinant of achieving vaginal delivery and is associated with induction-to-vaginal delivery time interval.     

Noncontraceptive health benefits of intrauterine devices: a systematic review

Most women and their clinicians are unaware that IUDs confer important noncontraceptive health benefits. This review summarizes the evidence from published articles on this topic. We conducted a series of systematic literature searches to identify articles on the noncontraceptive health benefits of IUD use. We reviewed the potentially pertinent ones for content, grouped them according to type of IUD, and evaluated them using the U.S. Preventive Services Task Force rating system. Over 500 titles were identified and several hundred abstracts were reviewed. Use of nonhormonal IUDs (plastic and copper) was associated with a decrease in endometrial cancer. The levonorgestrel intrauterine system can treat a variety of gynecological disorders, including menorrhagia and anemia. The levonorgestrel system has also been used successfully as part of hormone replacement therapy, as adjuvant therapy with tamoxifen, and as an alternative to hysterectomy for women with bleeding problems. Like oral contraceptives, intrauterine contraceptives confer important noncontraceptive health benefits.     

Risk of uterine rupture in women undergoing trial of labour with a history of both a caesarean section and a vaginal delivery

Purpose  

To determine the risk of uterine rupture for women undergoing trial of labour (TOL) with both a prior caesarean section (CS) and a vaginal delivery.