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Notes: Objective To compare by randomized prospective clinical trial the outcome of labours which are managed with the intention to leave the membranes intact, compared with the practice of elective artificial rupture of the membranes (ARM) in early established labour.Design Prospective randomized controlled trial of low risk women admitted in spontaneous labour, with intact membranes.Setting The labour ward of St. James's University Hospital, Leeds, UK.Subjects 362 women in spontaneous labour with intact membranes and no evidence of fetal distress, between 37 and 42 weeks gestation. During the course of the trial it was found that some randomization cards could not be accounted for and a system of daily checks was instituted. The results were analysed for all recorded women (n= 362) and after institution of the more rigorous system (n= 120).Main outcomes measured The duration of each phase of labour, epidural rate, prevalence of an abnormal cardiotocograph (CTG) (assessed blind), method of delivery and neonatal outcome.Results 178 of the 183 women (97%) in the ARM group had their membranes ruptured in early labour, and 83 (46%) of the 179 women allocated to non-intervention had ARM performed at some stage. A significant decrease in the duration of labour (mean 8.3, SD 4.1 h vs mean 9.7, SD 4.8h, n = 156; P= 0.05) was found amongst primigravidae allocated to ARM when compared with non intervention. The duration of the second stage of labour was unaffected. In the ARM group the epidural rate was higher and labour was more often complicated by CTG abnormalities. There were no differences in the method of delivery, fetal condition at birth (cord blood lactate, Apgar score) or postpartum pyrexia between the ARM and non-intervention groups. The same trends were observed when analysis was confined to women entered into the trial after the system of rigour was instituted.Conclusion Routine ARM results in labour that is slightly shorter than if the membranes are allowed to rupture spontaneously but more epidurals are used suggesting that labour is more painful. There are fewer fetal heart rate abnormalities if the membranes are left intact but amniotomy has no effect on fetal condition at birth.

Notes: Objectives To review the experience of the University of Toronto Perinatal Complex, Ontario, Canada concerning antenatally diagnosed monoamniotic twin pregnancies; and to compare our results with cases reported in the literature with respect to antenatal surveillance and perinatal outcome.Methods A retrospective chart review of all twin gestations from 1993 to April 2000 was performed. A systematic review of the literature, 1966 to April 2000, of perinatal outcome in monoamniotic twin pregnancies was undertaken.Setting All monoamniotic twin gestations at the University of Toronto.Results Case-series: 25 prenatally diagnosed monoamniotic twin pregnancies were identified. Seven pregnancies were affected by fetal anomalies. One fetus died at 29 weeks. Neonatal complications occurred below 33 weeks of gestational age and were related to immaturity. Systematic review of the literature: 49 studies met our selection criteria and reported 88 cases diagnosed antenatally. Fourteen pregnancies were affected by major congenital anomalies. Twenty fetuses died after 24 weeks of gestation. Neonatal complications varied widely in severity and depended on gestational age at birth. The risk of intrauterine fetal death was 10% at the University of Toronto and 12% in the review of the literature.Discussion Our experience, the largest so far, suggests that regular fetal surveillance and appropriate steroid administration leads to a good perinatal outcome. The risk of fetal death (10%–12%) is lower than the previously quoted risk of 30%–70%. A careful review of obstetric interventions and further work examining outpatient surveillance of monoamniotic twin pregnancies are needed. The best treatment of monoamniotic twin pregnancies can only be determined by randomised trials.