A comparison of three methods for inducing labor: oral prostaglandin E2, buccal desaminooxytocin, intravenous oxytocin

A study of labor induction in 325 patients is reported. Group I (77 patients with Bioshop's scores 0-6) and 2 (69 patients with Bishop's scores 7-12) were given 0.5 mg prostaglandin E2 every half hour (maximum 5 mg per day). Group 3 (87 patients with Bishop's scores 0-6) was givne 50 International units of buccal desaminooxytocin every half hour (maximum 500 International units per day). In Group 4 (92 patients with Bishop's scores 7-12), labor was induced by primary amniotomy and automatic oxytocin infusion by the Cardiff method. In groups 1, 2 and 3, 45 per cent, 74 per cent and 41 per cent delivered within 48 hours, while 100 per cent in group 4 delivered within 24 hours. No differences were found in either the frequency of cesarean section or the incidence of low Apgar scores. A higher, but not statistically significant frequency of vacuum extraction was found in the Cardiff group (25 per cent) than in the tablet-induced groups (15 per cent). There was, however, a significantly higheroccurrence of alterations in fetal heart rate which led to instrumental intervention to hasten delivery in the Cardiff group compared to the tablet-induced patients.     

Ripening of the uterine cervix and induction of labour at term with prostaglandin E2 in viscous gel.

In order to achieve ripening of the uterine cervix or induce labour in patients at term with an unfavourable cervical state, 1 mg of prostaglandin E2 (PGE2), suspended in a viscous gel, was instilled into the cervical canal. In a pilot study, 41 patients received the PGE2-gel. Twenty-three of these, (56%), went into labour, and delivery occurred without further stimulation within 15 hours. In the remaining 18 patients, there was a marked improvement of the cervical state, which changed from an average (modified) Bishop score of 2.5 to 6.1 within 24 hours. In a double-blind study comprising 20 nulliparae, 10 received gel containing PGE2 and 10 gel without prostaglandin. Cervical state did not change significantly (Bishop score 3.6 and 4.0) after 24 hours in patients receiving placebo gel. In those receiving PGE2 gel, 8 went into labour and were delivered without further induction within 13 hours. Two patients showed an increase in Bishop score from 3 to 6 and 7, respectively, after 24 hours. They were then induced by oxytocin and delivery occurred after 8 and 10 hours. The results suggest that administration of PGE2 intracervically can induce ripening of the cervix in patients at term with an unfavourable cervical state, and thus facilitate delivery.     

Cervical ripening and labor outcome with preinduction intracervical prostaglandin E2 (Prepidil) gel

Delivery with an unfavorable cervix using oxytocin is frequently unsuccessful. Used widely in Europe and increasingly in this country, locally applied prostaglandin E2 appears to improve labor induction. The present study prospectively evaluated the efficacy and safety of a prostaglandin gel (0.5 mg) placed intracervically. The use of the gel, when compared to a control group who received no pretreatment prior to labor induction, resulted in improved Bishop scores (7.5 +/- 1.0 vs. 1.8 +/- 0.3, P less than 0.0001), reduced induction to delivery intervals (10.1 +/- 2.1 vs. 20.6 +/- 2.0 hours), reduced oxytocin infusion duration (10.0 +/- 2.1 vs. 20.0 +/- 2.3 hours. P less than 0.0001) resulting in a lower cesarean delivery rate, 26 vs. 47 per cent (P greater than 0.05). Thirty-two per cent of patients receiving the prostaglandin gel labored and delivered within 12 hours and required no oxytocin. In addition, the use of prostaglandin E2 gel appeared safe in that no patient experienced an untoward reaction. Two cases of uterine hyperstimulation occurred that required uterine tocolysis but were not associated with fetal distress. The use of prostaglandin gel appears to be a safe and effective method to improve cervical inducibility in patients undergoing induction for a variety of maternal and fetal indications.     

The benefits and risks of amniocentesis for the assessment of fetal lung maturity.

Amniocentesis for estimation of the lecithin: sphingomyelin (L/S) ratio was performed on 483 patients on 552 occasions. The introduction of this test has been associated with a highly significant (p less than 0-001) decrease of 59 per cent in the incidence of respiratory distress syndrome. The finding of a low L/S ratio (less than 2-0) enabled delivery to be deferred until lung maturity had been reached in 43 (10-3 per cent) of the 419 patients who had successful amniocentesis. Fetal death occurred after amniocentesis in two patients (0-41 per cent). One fetus died after haemorrhage occurred behind an anterior placenta and the other died of exsanguination. Failed amniocentesis occurred in 64 patients (13-2 per cent), and was more common when the placenta was anterior or was not located before the procedure and when fetal growth was retarded. Fetal distress in labour occurred more commonly after failed amniocentesis. Spontaneous labour followed amniocentesis in 47 patients (9-7 per cent) and was significantly more prone to occur after 38 weeks gestation. Rhesus isoimmunization did not occur in any of the rhesus-negative patients who delivered rhesus-positive babies and who were screened six or more months after amniocentesis, although anti-D immunoglobulin was not given routinely after amniocentesis. Suggestions are made as to how the success rate of this valuable procedure can be improved and how some of the serious fetal and maternal sequelae can be avoided.     

Transcutaneous electrical nerve stimulation (TENS) in obstetrics

Labour pains have been influenced by TENS (electrodes placed at Th10 to L2) in 78 women (control group comprising 46 women) during delivery. No electrostimulation of the sacral segments was carried through. The two groups were comparable well because of similarities in their age, the babies' size at birth and equal conditions during delivery. The first TENS effect observed was a marked reduction of duration of labour with no increase in pathological cardiotocographic findings. With TENS applied, primiparae have been delivered after an average of 244 minutes (control group after 358 minutes) and multiparae after 159 minutes (control group after 256 minutes). 87 per cent of the TENS group's labour and 61 per cent of the control group's labour were induced. Using TENS, clearly reduced amounts of spasmolytic agents (44:74 per cent) had to be administered during labour. 41 per cent of the TENS group women suffered episiotomy or laceration (control group: 52 per cent). 80 per cent of the women in whom TENS had been applied considered TENS as facilitating childbirth. 68.4 per cent of the primipara TENS group (control group: 18.2 per cent) and 80 per cent of te multipara TENS group (control group: 25 per cent) indicated the labour pains to be absolutely endurable (with TENS applied, the labour pains did not start until about 15 minutes prior to delivery--lack of sacral electrodes?). However, the experience gathered as well as an assessment of the questionnaires filled in, indicate that, with all the technical equipment available, women in labour expect the medical staff to provide them with care, understanding and personal devotion.     

Routine induction of labour with extra-amniotic prostaglandin E2 in a viscous gel.

Prostaglandin E2, 350 microgram dispersed in a viscous gel, tylose, was introduced into the extra-amniotic space as a single dose in 285 patients to induce labour. With a favourable cervix, 82 per cent of multiparae and 50 per cent of primiparae were successfully induced. With unfavourable induction features, the success rates were 48 per cent and 24 per cent respectively. In the remaining patients, all but four were successfully delivered when intravenous oxytocin was also used. The method was safe, simple and inexpensive and had many advantages for patients and nursing staff.     

Risk of pre-term delivery in patients with previous pre-term delivery and/or abortion

Patients with a history of two or more pregnancies which ended spontaneously before 37 weeks gestation had an increased risk of spontaneous pre-term labour and delivery in future pregnancies. This increased risk related mainly to previous second trimester abortions and not to previous first trimester abortions. Patients with one previous spontaneous pre-term labour and delivery had a 37 per cent risk, and those with two or more pre-term deliveries a 70 per cent risk of again delivering pre-term. There appeared to be no beneficial effect of cervical suture on the incidence of pre-term delivery in these patients.     

Induction of labor in patients with missed abortion and fetal death in utero with protaglandin E2 suppositories

Labor was successfully induced in 20 patients with a diagnosis of missed abortion or intrauterine fetal death (IUFD) by intravaginal administration of prostaglandin E2 suppositories. Fifteen patients delivered with the prostaglandin alone while a concomitant oxytocin infusion was employed to augment contractions in the other five patients. The mean induction-delivery time was 9.80 hours; nulliparous patients delivered in a mean time if 7.78 hours, parous patients in a mean time of 12.29 hours. The uterus appeared to be sensitive to the PGE2 stimulation in all patients and all were delivered completely without the need for surgical intervention. Fifty per cent of patients were delivered within 8 hours and 80 per cent by 12 hours. The side effects associated with prostaglandin administration--vomiting, diarrhea, and temperature elevation--were well tolerated and therapy did not have to be terminated in any patient. The administration of PGE2 vaginal suppositories offers an effective and safe technique for the induction of labor in patients with IUFD. Labor can be induced with PGE2 suppositories as soon as the diagnosis of IUFD is confirmed, which eliminates the need for waiting until spontaneous labor occurs.     

Prostaglandin E2 vaginal suppository for induction of labour: an efficient, safe and popular method

Two different methods for induction of labour were randomly used in 100 women with a favourable cervix. The patients were treated with either prostaglandin vaginal suppositories containing 2.5 mg PGE2 in a base of Witepsol S55 (Dynamit Nobel) or intravenous infusion of oxytocin. The PGE2 vaginal suppository was significantly more efficient than the intravenous infusion of oxytocin in relation to the time interval from the start of induction of labour to delivery. Also the percentage of women who delivered within 48 hours (success rate) was higher in the suppository group. Significantly more women in the suppository group found this induction method recommendable.     

Vaginal misoprostol induction of labour: a Nigerian hospital experience.

We reviewed our experience with vaginal misoprostol induction of labour in 339 consecutive women with a live fetus and intact fetal membrane using 100 mcg 12-hourly until labour was established. The labours were monitored using the WHO partograph protocol. Two hundred and sixty-five women had a successful induction while 74 had an emergency caesarean section because of cephalopelvic disproportion (63.5%), fetal distress (14.9%), prolonged labour (12.2%), antepartum haemorrhage (6.8%) and other indications (2.8%). The induction delivery interval among the women who had successful induction ranged from 3 hours 42 minutes to 26 hours 15 minutes with a mean of 9 hours 23 minutes (SD 2 hours 41 minutes). Most (73.6%) of these patients delivered within 12 hours of starting induction, the majority (95.3%) requiring only 100 mcg to go into established labour. Complications recorded in this series include fetal distress in 32 (9.4%), postpartum haemorrhage in 23 (6.8%), hyperstimulation in six (1.8%), uterine rupture in one (0.3%), birth asphyxia in eight (2.5%), admission in neonatal intensive care ward in five (1.5%), neonatal death in one (0.3%) and maternal death in one (0.3%) patient. In conclusion, misoprostol was found not only to be efficacious but relatively safe in comparison to other methods of induction in use in our hospital.     

Failed Induction of Labour

Over a 15-month period 1,057 consecutive inductions of labour were performed representing a 10% induction rate; 174 (16.5%) of these patients were delivered by Caesarean section of which 74 (7.0%) were for failed induction of labour, 58 (5.5%) for fetal distress, 19 (1.8%) for cephalopelvic disproportion, 6 for malposition and 17 for other reasons. The mean cervical score at induction of labour was 5.7 and 5.5 for cephalopelvic disproportion (CPD) and malposition respectively but was 4.0 for failed induction. The mean cervical dilatation at the time of Caesarean section was 5.7 cm and 6.6 cm for CPD and malposition respectively whereas it was 3.5 cm for failed induction. Mean maximum dose of oxytocin was 19.2 milliunits per minute (mu/min) and 22.5 mu/min for CPD and malposition respectively whereas it was 24.7 mu/min for cases of failed induction. Nulliparas with a cervical score of 3 or less had a 65.4% Caesarean section rate of which more than two-thirds were for failed induction of labour. Analysis of indications for induction of labour revealed that a fair number of inductions had debatable obstetric indications. Tailoring induction of labour to the cervical score and indication might reduce the Caesarean section rate for failed induction of labour. Rational management to ensure an adequate dose of oxytocin and sufficient time in the first stage of labour is important. Failed induction of labour may be differentiated from failure of labour progress due to CPD or malposition.     

Pregnancy termination in the 2d and 3d trimester with prostaglandins depending on the cervix status

Termination of pregnancy was performed in a standardized, on the cervical state depending manner in 48 patients with abortion between the 16th and 27th week of gestation and in 20 women with intrauterine fetal death (IUFD) between the 28th and 41st week of gestation. At a Bishop-Score (B.S.) less than 7 cervical ripening was induced by intracervical application of 0.1 mg sulprostone gel. In patients with a very unripe cervix (B.S. less than or equal to 3) local applications of prostaglandin gel were repeated at 6 hours intervals until a B.S. greater than or equal to 5 had been achieved. For induction of labour 0.5 mg sulproston was injected intramuscularly after at least one sulproston gel application in a range between B.S. greater than or equal to 5 to 7. At a B.S. 7 intravenous infusion of oxytocin was administered, if necessary, for augmentation of labour. Most of the patients received epidural anaesthesia before induction of labour. The time interval between the beginning of the procedure and expulsion of the fetus ranged from 6.5 to 49.5 hours (mean = 26.3 h) in the abortion group and from 2.0 to 46.0 hours (mean = 20.0 h) in the IUFD group. The median interval between induction of labour and abortion/delivery was 4.3 hours (range: 0.5-27.0), and 5.5 hours (range: 0.7-9.3 h) respectively. No surgical interventions were necessary in any of the patients, and no cervical lesions occurred. Undesired systemic side effects to prostaglandins were observed in only 4 out of the 68 cases.(ABSTRACT TRUNCATED AT 250 WORDS)     

Induction of Labour in Nulliparas with Poor Cervical Score: Oxytocin or Prostaglandin Vaginal Pessaries?

In a previous study nulliparas with poor cervical score (less than 5 out of 10) had a 43.5% Caesarean section (CS) rate of which 55% were for failed induction when labour was induced by artificial rupture of membranes and oxytocin infusion. In this study induction of labour by 2 doses of 3 mg prostaglandin E2 (PGE2) vaginal pessaries, 4 hours apart, and if necessary by artificial rupture of membranes and oxytocin infusion 24 hours later, resulted in a CS rate of 23.7% of which 38.9% were for failed induction. The latter regimen resulted in a significantly lower CS rate compared with labour induced by oxytocin infusion and rupture of membranes without the use of prostaglandins (p less than 0.001). In the prostaglandin group 53.3% were established in labour within 24 hours of inserting the pessary and in these patients the CS rate was 18.5%. In those who did not start labour and needed rupture of membranes and oxytocin infusion 24 hours after the first pessary, 34 (47.9%) had a good cervical score (greater than or equal to 6 out of 10) and 37 (52.1%) had a poor cervical score (less than or equal to 5 out of 10) at the time of amniotomy. The CS rates in these groups were 8.8% and 48.6% respectively (p less than 0.001). In nulliparas with poor cervical score induction is better performed with vaginal prostaglandin pessaries in order to reduce the high CS rate associated with artificial rupture of membranes and oxytocin infusion.     

Normal values for fetal scalp tissue pH during labour.

Normal values for fetal scalp tissue pH during labour were determined by using a glass electrode (Kontron-Roche). A total of 132 recordings was obtained and 84 (64 per cent) were of good quality. After a good quality recording had been obtained, there were 64 infants with an Apgar score of 9 or 10 at one and five minutes after delivery. The 64 recordings showed pH values (Mean +/- 2SEM) of 7.38 +/- 0.12 six hours before delivery and 7.28 +/- 0.12 at the time of delivery. Between the 5th and 55th minutes of the second stage of labour the pH (Mean +/- 2SEM) fell from 7.30 +/- 0.14 to 7.20 +/- 0.13.     

SQ 20,881: effect on eclamptic--pre-eclamptic women with postpartum hypertension

The renin-angiotensin system has been implicated in the genesis of pre-eclampsia. To avoid fetal toxicity, five women were studied who developed hypertension, proteinuria, and edema in the last trimester of pregnancy and whose BP elevation persisted immediately postpartum. At about 6 hours after delivery the CE enzyme inhibitor (SQ 20,881) was given in incremental doses ranging from 0.25 to 3.0 mg. per kilogram intravenously, before and after diuresis with furosemide, 40 mg. intravenously. BP was measure every 2 minutes and PRA and angiotensin II concentration before treatment, 30 minutes after 0.25 to 0.30 mg. per kilogram, and 30 minutes after 2.0 to 3.0 mg. per kilogram. Echocardiographic assessment of CI and PVR was performed before treatment and after a maximum dose in three patients. Before diuresis, CE blockade had no effect on heart rate, BP, CI, PVR, or PRA, regardless of whether the patient was in positive or negative fluid balance or was sodium loaded or restricted over the preceding 24 hours. Angiotensin II fell by 77 and 10 per cent, respectively, after 0.25 mg. per kilogram was given to two patients, but rose slightly in the other three patients, then fell an average of 46 per cent after 1.0 to 3.0 mg. per kilogram were given. After diuresis, 1.0 mg. per kilogram resulted in a 24 per cent fall in BP which persisted for 3 hours in two patients and a 14 per cent fall which lasted for 30 minutes after 1.0 or 3.0 mg. per kilogram in a third patient. It is concluded that the BP elevation which persists after delivery in certain patients with pre-eclampsia is not angiotensin II dependent.     

Is it worth inducing labour in women with a previous caesarean delivery?

The aim of this study was to determine the outcome of labour induction following a previous caesarean section. A total of 43 cases were identified; 23 out of those (53.5%) achieved vaginal delivery. The remaining 20 cases (46.5%) had a repeat caesarean. A total of 25 women had ≥ 1 previous vaginal deliveries and in the remaining 18, the previous caesarean was the only pregnancy carried before the current pregnancy. Out of the 23 women who successfully delivered vaginally, 16 cases (69.6%) had a history of ≥ 1 previous vaginal delivery, while no such history was reported in the remaining seven cases (30.4%). The indications for a repeat caesarean were failed induction of labour in five cases (25%); fetal distress in seven cases (35%); failure-to-progress in eight cases (40%). Only one case (2.3%) of uterine rupture was reported. In conclusion, labour induction following a previous caesarean section is an effective and safe intervention. Vaginal delivery can be anticipated in the majority of these women. This study emphasises the need for thorough counselling of these women regarding benefits and risks of induction of labour, and also highlights the necessity of shared patient-doctor decision-making.     

Induction of labour: how close to the evidence-based guidelines are we?

The aim of this study was to assess the indications and methods used for induction of labour (IOL), to determine whether induction was performed as per local guidelines, to ensure the Royal College of Obstetricians and Gynaecologists/National Institute for Clinical Excellence (RCOG/NICE) guidelines were adhered to within the department and finally, identify areas for improvement in women's care. We retrospectively analysed 95 cases of IOL managed between 1 May and 30 June 2003 at City Hospital, Birmingham, UK. A total of 95 out of 569 (16.7%) deliveries were induced over the period of study. Indications for IOL and their documentation in the case-notes showed 60 - 70% compliance with guidelines. Pre-IOL cervical ripening with prostaglandin E2 (PGE2) was performed in 42 cases out of 65, showing 64.6% compliance with guidelines. All cases who had pre-IOL cervical ripening with PGE2 were closely monitored during ripening, showing 100% compliance. A total of 79 cases out of 95 (83.2%) achieved vaginal delivery. However, eight of those (8.4%) required instrumental delivery. More than 50% of women delivered within 12 h of starting IOL. Five cases (5.3%) had failed IOL. The overall caesarean section (CS) rate was 16.8%. Maternal and fetal complications were relatively uncommon during the study period. Uterine hyperstimulation was reported in only one case (1.1%) in this study. Full compliance with evidence-based guidelines was achieved in some aspects of this audit, while other aspects showed no or little compliance. IOL is an effective and safe intervention in modern obstetric practice. Regardless of cervical status and parity, vaginal delivery can be anticipated in the majority of women undergoing labour induction.     

Once cesarean section--always cesarean section?

Between 1975 and 1985 from 522 patients, who had undergone caesarean section during their previous delivery or deliveries, per cent 63 have been delivered vaginally and 37 per cent with a caesarean section (52.8% primary, 47.2% secondary). The rate of spontaneous labour was higher, if patient had a spontaneous delivery before caesarean section or the first caesarean section has been performed because of a placenta praevia, a breech presentation or a fetal distress syndrome. Cephalopelvic disproportion went on in 67.2 per cent with a caesarean section. Rupture of the scare occurred in 2.9 per cent. Expectative management of delivery is justified following previous caesarean section. Oxytocin infusions are possible in cases if internal tocography will be done.     

Induction of labour after a previous caesarean section: a retrospective study in a district general hospital.

A retrospective study was undertaken in a district general hospital to identify factors associated with vaginal delivery, as opposed to caesarean section, in women undergoing induction of labour after a previous caesarean section. The study was undertaken over 9 years (April 1994 - May 2003) and included patients in their second or subsequent pregnancy who had previously had one lower segment caesarean delivery and in whom labour had been induced. Records were extracted from a database and anonymised. Vaginal delivery after induction of labour was attempted in 81 patients of whom 64 (79.0%) subsequently delivered vaginally. There were few complications and no cases of uterine rupture. Two factors had a statistical significant relationship with vaginal birth after induction of labour; occipito-anterior position (OR 10.18, 95% CI 1.42 - 112.7, Yates corrected chi2; p = 0.001) and more than one previous birth (OR 4.76, 95% CI 1.28 - 21.67, p = 0.017). Other associations were explored but were not statistically significant. This paper contributes to the literature on factors associated with vaginal delivery after induction of labour and previous caesarean section, which may inform the selection of cases, and consequent success rates for vaginal delivery.     

Induction of labor with oral prostaglandin E2.

Prostaglandin E (PGE2) was administered orally for induction of labor to 100 patients. Active labor and progression occurred in 92 per cent of these cases. The dosage regimen used was 0.5 to 1.5 mg. hourly. Amniotomy was performed in most cases once active labor and progression were noted. There were 83 vaginal deliveries and 12 cesarean sections. There were eight failure of induction, one patient left the study, and one was not delivered at that admission. Fetal distress occurred in 10 patients but this was related to cord and placental problems and not to PGE2 per se. Side effects were minimal, the most prominent being nausea and vomiting. Total labor in hours compares to normal labor. Over-all, labor in primigravidas averaged 10.15 hours and 6.5 hours in multiparas. There was a direct relationship of the Bishop score to the start of active labor and progression. PGE2 appears safe and efficacious for inductions of labor at terms.