British Journal of Obstetrics and Gynaecology February 1978. Vol85. pp 109-113
A RANDOMIZED CONTROLLED TRIAL OF SELECTIVE PLANNED DELIVERY BY
D. H. MARTrN,*Senior Tutor W. THOMPSON, Senior Lecturer
J. H. M. PINKERTON, Professor Department of Midwifery and Gynaecology AND
J. D. WATSON, Senior Tutor Department of Community Medicine, The Queen's University of Belfast, Northern Ireland Summary
A prospective randomized controlled trial designed to investigate selective planned delivery is reported: 264 obstetrically normal women in the 38th week of pregnancy were admitted to this trial and 184 completed it. The infants of mothers in the planned delivery group had higher serum bilirubin levels on the fifth day post partum than control infants but no baby required treatment for hyperbilirubinaemia. Mothers in the planned delivery group required significantly greater amounts ot' pethidine while control mothers had a significantly higher incidence of meconium staining of the amniotic fluid. However, the infants in the two groups had similar Apgar scores at birth. There was one stillbirth in the control group; this was due to unrecognized fetal hypoxia during labour induced at 42 weeks for postmaturity.
METHODS Case notes relating to all booked patients in the 38th week of their pregnancy were scrutinized on the day before their next visit. Patients were considered suitable for admission to the trial if (i) all past and/or present pregnancies were obstetrically normal, (ii) booking relating to the current pregnancy took place not later than the 18th week, the menstrual cycle did not exceed 35 days, no contraceptive pill was taken nor was there any pregnancy for at least three months before the last menstrual period and the size of the uterus at booking corresponded to the period of amenorrhoea Only 264 patients, representing some 16 per cent of all the women examined
I N selective planned delivery the initiation of labour is achieved by artificial means for other than medical reasons. We previously reported a pilot study (Pinkerton et al, 1975) carried out at the Royal Maternity Hospital, Belfast, which showed that, provided strict criteria were used, selective planned delivery appeared safe for both mother and fetus. We now describe further work based on a prospective randomized trial comparing spontaneous and selective planned delivery in a sample of 264 obstetrically normal patients.
* Present
address: Consultant Obstetrician and Gynaecologist, Altnagelvin Hospital, Londonderry, Northern Ireland. 109
110
MARTIN, THOMPSON, PINKERTON AND WATSON
fasting at 0830 hours. The forewaters were punctured soon afterwards and the Bishop score and cervical dilatation recorded. An infusion of intravenous oxytocin was commenced and regulated by the nursing staff with the aid of an Ivac drip counter. The oxytocin dosage started at 2.5 mU/minute and was doubled at 30-minute intervals until a satisfactory uterine response was achieved. Subsequently, the dose was varied to maintain adequate contractions. All induced patients were continuously monitored using internal tocography and a fetal scalp electrode. Patients in the control group had, if necessary, augmentation of labour by puncture of the forewaters or intravenous oxytocin. When possible, these patients also were monitored. For each of the 264 patients admitted to the trial a questionnaire was completed and the data transferred to punched cards for computer analysis. Randomization was checked at two stages during the trial (Table I). No significant differences were found between planned delivery and control groups at the start of the trial with regard to several selected indices, and moreover there were no significant differences between the two groups for the same factors after exclusions.
at 38 weeks, fulfilled these criteria and they were asked to take part in the trial. These patients were allocated, using random number tables, to either the ‘planned delivery’ or the ‘control’ groups. Patients in the former group were to have labour induced at 39 weeks gestation, while patients in the latter group were to await the spontaneous onset of labour until 42 weeks unless induction was required earlier for medical reasons. At the 38th week the 264 patients were examined vaginally at the antenatal clinic and admitted to the trial if no abnormality was detected. At this stage, 34 patients were excluded. In the planned group the indications for exclusion were : obstetric abnormality (8 patients), refusal (10 patients), defaulter (6 patients) and spontaneous labour before attending the clinic (one patient). Of the controls, 9 patients were excluded for obstetric reasons. This left 230 obstetrically normal patients in the trial : 106 in the planned delivery group and 124 controls, who progressed to the next stage of the trial. Those in the planned delivery group were given a date for admission, but 13 came into spontaneous labour and one was excluded due to medical reasons, leaving 92 patients who had an induction and planned delivery. In the control sample, 32 patients were excluded because of the development of obstetric abnormality or failure to go into spontaneous labour before 42 weeks gestation, leaving 92 patients who started labour spontaneously. Patients for planned delivery were admitted
RESULTS There was no significant difference between groups for mode of delivery (x2 = 2.05, df = 2, 0. 4>P >0. 3) ; 18.5 per cent of patients in the planned delivery group and 20.7 per
TABLE I Indices for patients in selective planned delivery and control groups Selected indices at entry to trial
Maternal age at booking (years) Parity Menstrual cycle (days) Gestation at booking (weeks) Uterine size at booking (weeks) Number of patients
Selected indices at completion of trial
Planned delivery
Control
Planned delivery
Control
Mean&SD
Mean*SD
MeanfSD
MeaniSD
26.0614.87 1.30&1.32 28.21&2.02 13.1712.40 13.4512.50
25.46&4.79 1.20h1.47 28.1712.05 13.48+2.33 13.74k2.45
25.7714.70 1.1511.20 28.23*1.80 13.29&2.36 13.5912.40
25.75k4.76 1.25*1.36 28.20+1.93 13.22&2.12 13.4912.17
131
133
92
92
111
SELECTIVE PLANNED DELIVERY
cent of the controls required assisted delivery. There were four Caesarean sections in the planned delivery group, the indications being breech presentation diagnosed at induction in a primagravida who then made poor progress in labour, two patients with cephalopelvic disproportion, and one patient with fetal distress. In the control group there was one Caesarean section for cephalopelvic disproportion. The induction to delivery interval (meanfSD) in the planned delivery group was 8.3 f O .52 hours compared with a duration of labour in the controls of 6.8f0.40 hours, taking the onset of labour as the first awareness of regular painful contractions (F = 5.51, df = 1,182, P
A RANDOMIZED CONTROLLED TRIAL OF SELECTIVE PLANNED DELIVERY BY
D. H. MARTrN,*Senior Tutor W. THOMPSON, Senior Lecturer
J. H. M. PINKERTON, Professor Department of Midwifery and Gynaecology AND
J. D. WATSON, Senior Tutor Department of Community Medicine, The Queen's University of Belfast, Northern Ireland Summary
A prospective randomized controlled trial designed to investigate selective planned delivery is reported: 264 obstetrically normal women in the 38th week of pregnancy were admitted to this trial and 184 completed it. The infants of mothers in the planned delivery group had higher serum bilirubin levels on the fifth day post partum than control infants but no baby required treatment for hyperbilirubinaemia. Mothers in the planned delivery group required significantly greater amounts ot' pethidine while control mothers had a significantly higher incidence of meconium staining of the amniotic fluid. However, the infants in the two groups had similar Apgar scores at birth. There was one stillbirth in the control group; this was due to unrecognized fetal hypoxia during labour induced at 42 weeks for postmaturity.
METHODS Case notes relating to all booked patients in the 38th week of their pregnancy were scrutinized on the day before their next visit. Patients were considered suitable for admission to the trial if (i) all past and/or present pregnancies were obstetrically normal, (ii) booking relating to the current pregnancy took place not later than the 18th week, the menstrual cycle did not exceed 35 days, no contraceptive pill was taken nor was there any pregnancy for at least three months before the last menstrual period and the size of the uterus at booking corresponded to the period of amenorrhoea Only 264 patients, representing some 16 per cent of all the women examined
I N selective planned delivery the initiation of labour is achieved by artificial means for other than medical reasons. We previously reported a pilot study (Pinkerton et al, 1975) carried out at the Royal Maternity Hospital, Belfast, which showed that, provided strict criteria were used, selective planned delivery appeared safe for both mother and fetus. We now describe further work based on a prospective randomized trial comparing spontaneous and selective planned delivery in a sample of 264 obstetrically normal patients.
* Present
address: Consultant Obstetrician and Gynaecologist, Altnagelvin Hospital, Londonderry, Northern Ireland. 109
110
MARTIN, THOMPSON, PINKERTON AND WATSON
fasting at 0830 hours. The forewaters were punctured soon afterwards and the Bishop score and cervical dilatation recorded. An infusion of intravenous oxytocin was commenced and regulated by the nursing staff with the aid of an Ivac drip counter. The oxytocin dosage started at 2.5 mU/minute and was doubled at 30-minute intervals until a satisfactory uterine response was achieved. Subsequently, the dose was varied to maintain adequate contractions. All induced patients were continuously monitored using internal tocography and a fetal scalp electrode. Patients in the control group had, if necessary, augmentation of labour by puncture of the forewaters or intravenous oxytocin. When possible, these patients also were monitored. For each of the 264 patients admitted to the trial a questionnaire was completed and the data transferred to punched cards for computer analysis. Randomization was checked at two stages during the trial (Table I). No significant differences were found between planned delivery and control groups at the start of the trial with regard to several selected indices, and moreover there were no significant differences between the two groups for the same factors after exclusions.
at 38 weeks, fulfilled these criteria and they were asked to take part in the trial. These patients were allocated, using random number tables, to either the ‘planned delivery’ or the ‘control’ groups. Patients in the former group were to have labour induced at 39 weeks gestation, while patients in the latter group were to await the spontaneous onset of labour until 42 weeks unless induction was required earlier for medical reasons. At the 38th week the 264 patients were examined vaginally at the antenatal clinic and admitted to the trial if no abnormality was detected. At this stage, 34 patients were excluded. In the planned group the indications for exclusion were : obstetric abnormality (8 patients), refusal (10 patients), defaulter (6 patients) and spontaneous labour before attending the clinic (one patient). Of the controls, 9 patients were excluded for obstetric reasons. This left 230 obstetrically normal patients in the trial : 106 in the planned delivery group and 124 controls, who progressed to the next stage of the trial. Those in the planned delivery group were given a date for admission, but 13 came into spontaneous labour and one was excluded due to medical reasons, leaving 92 patients who had an induction and planned delivery. In the control sample, 32 patients were excluded because of the development of obstetric abnormality or failure to go into spontaneous labour before 42 weeks gestation, leaving 92 patients who started labour spontaneously. Patients for planned delivery were admitted
RESULTS There was no significant difference between groups for mode of delivery (x2 = 2.05, df = 2, 0. 4>P >0. 3) ; 18.5 per cent of patients in the planned delivery group and 20.7 per
TABLE I Indices for patients in selective planned delivery and control groups Selected indices at entry to trial
Maternal age at booking (years) Parity Menstrual cycle (days) Gestation at booking (weeks) Uterine size at booking (weeks) Number of patients
Selected indices at completion of trial
Planned delivery
Control
Planned delivery
Control
Mean&SD
Mean*SD
MeanfSD
MeaniSD
26.0614.87 1.30&1.32 28.21&2.02 13.1712.40 13.4512.50
25.46&4.79 1.20h1.47 28.1712.05 13.48+2.33 13.74k2.45
25.7714.70 1.1511.20 28.23*1.80 13.29&2.36 13.5912.40
25.75k4.76 1.25*1.36 28.20+1.93 13.22&2.12 13.4912.17
131
133
92
92
111
SELECTIVE PLANNED DELIVERY
cent of the controls required assisted delivery. There were four Caesarean sections in the planned delivery group, the indications being breech presentation diagnosed at induction in a primagravida who then made poor progress in labour, two patients with cephalopelvic disproportion, and one patient with fetal distress. In the control group there was one Caesarean section for cephalopelvic disproportion. The induction to delivery interval (meanfSD) in the planned delivery group was 8.3 f O .52 hours compared with a duration of labour in the controls of 6.8f0.40 hours, taking the onset of labour as the first awareness of regular painful contractions (F = 5.51, df = 1,182, P
