Dermot MacDonald

The Dublin randomized controlled trial of intrapartum fetal heart rate monitoring

In a randomized controlled trial involving 12,964 women, a policy of continuous electronic intrapartum fetal heart monitoring was compared with an alternative policy of intermittent auscultation, both policies including an option to measure fetal scalp blood pH. Women allocated to electronic fetal heart monitoring had shorter labors and received less analgesia. The caesarean delivery rates were 2.4% for electronic fetal heart monitoring and 2.2% for intermittent auscultation but this small difference arose from the identification of nearly twice as many fetuses with low scalp pH (less than 7.20) in the electronic fetal heart monitoring group. The forceps delivery rate was 8.2% in the electronic fetal heart monitoring group compared with 6.3% in the intermittent auscultation group, and this excess was explained by more instrumental deliveries prompted by fetal heart rate abnormalities. There were 14 stillbirths and neonatal deaths in each group, with a similar distribution of causes. There were no apparent differences in the rates of low Apgar scores, need for resuscitation, or transfer to the special care nursery. Cases of neonatal seizures and persistent abnormal neurological signs followed by survival were twice as frequent in the intermittent auscultation group, and this differential effect was related to duration of labor. Follow-up at 1 year of babies who survived neonatal seizures revealed three clearly abnormal infants in each group. The implications of these findings for both theory and practice are discussed.

Cerebral palsy among children born during the Dublin randomised trial of intrapartum monitoring

In a randomised trial involving 13,079 liveborn children intrapartum care by electronic fetal heart rate monitoring, with scalp blood sampling when indicated, was associated with a 55% reduction in neonatal seizures. Reassessment, when aged 4, of the 9 children in the intensively monitored group and 21 in the control group who survived after neonatal seizures showed that 3 such children in each group had cerebral palsy. A fourth child in the intensively monitored group with cerebral palsy had had transient abnormal neurological signs during the neonatal period. 8 other children in the intensively monitored group and 7 in the control group who had not had abnormal neurological signs in the neonatal period also had cerebral palsy. 16 (78%) of the total of 22 cases of cerebral palsy had not shown clinical signs suggestive of intrapartum asphyxia. Thus, compared with intermittent intrapartum monitoring, intensive monitoring has little, if any, protective effect against cerebral palsy.

TRAUMATIC INTRACRANIAL HAEMORRHAGE IN FIRSTBORN INFANTS AND DELIVERY WITH OBSTETRIC FORCEPS

Exclusive of breech presentation, traumatic intracranial haemorrhage was demonstrated at necropsy on 27 occasions in 36 420 consecutive firstborn infants. All 27 were forceps deliveries. The main conclusion is that serious injury to the forecoming head at birth is almost invariably a direct effect of forceps. The relevance of this conclusion to some aspects of contemporary obstetric practice is discussed briefly.

Pregnancy complicated by maternal heart disease at the National Maternity Hospital, Dublin, Ireland, 1969 to 1978

Three hundred eighty-seven pregnancies (295 patients) complicated by maternal heart disease, managed at the National Maternity Hospital, Dublin, Ireland, during the years 1969 to 1978, were reviewed. The incidence was 0.5%. Three hundred twenty-three (83.5%) were of rheumatic origin, 52 (13.4%) were congenital, and the remaining 12 (3.1%) were a miscellaneous group and included cases of cor pulmonale and coronary artery disease. There were two maternal deaths--one from congenital heart disease and one from postpartum suicide, unrelated to mild rheumatic heart disease. The perinatal mortality rate was 3.3%. Five pregnancies (three patients) were complicated by surgically uncorrected cyanotic congenital heart disease. One of the maternal deaths and three of the perinatal deaths occurred in this group. There were 38 episodes of cardiac failure (38 patients) in cases of rheumatic heart disease. The New York Heart Association grading was grade 1 in 15 (39%) of these before the onset of failure. Prophylactic antibiotics were not used and infective endocarditis did not occur. Therapeutic abortion was not practiced and a conservative approach was adopted in obstetric intervention and in all drug therapy.

Pregnancy in the diabetic patient: timing and mode of delivery.

The clinical outcome of 141 consecutive diabetic pregnancies managed in the National Maternity Hospital between January 1, 1979, and October 31, 1982, is described. Patients with gestational diabetes were excluded. There were 12 spontaneous abortions, and the perinatal mortality in 129 viable pregnancies was 31/1000. The malformation rate was 6.4%. Significant perinatal morbidity occurred in 20% of infants. The incidence of cesarean section was 20%. Spontaneous labor after 38 weeks occurred in 30% because there was a deliberate policy to allow all uncomplicated pregnancies to continue to term. This policy had benefits for the infant as well as the mother because there was a notable reduction in neonatal morbidity. Possible explanations of high cesarean section rates in other centers are discussed.

Serial changes in cardiac output during normal pregnancy: a Doppler ultrasound study

OBJECTIVES To determine the direction and magnitude of change in cardiac output (CO) during pregnancy. STUDY DESIGN We performed serial measurements of CO on five occasions from 24 weeks gestation to term and once during the puerperium in 26 normal pregnancies (156 measurements) using Doppler ultrasound measurement of flow velocity profiles and aortic root cross sectional area. RESULTS CO increased to 7.0 l/min by 32 weeks gestation, 49% above baseline values. It fell to 5.7 l/min by term, 21% above baseline. The peak in CO corresponded with an increase in heart rate to 91 beats/min, 32% above baseline. Stroke volume peaked at 36 weeks gestation, by which time CO had already begun to decline. CONCLUSIONS CO increased in a linear fashion until 32 weeks gestation and then declined to term, but to a value still greater than the postpartum baseline. These findings have obvious management implications for patients with serious heart disease complicating pregnancy.

Electronic fetal heart monitoring, auscultation, and neonatal outcome

In a large randomized, controlled study of fetal heart rate monitoring with either continuous electronic fetal heart monitoring or auscultation at specified intervals, only one pattern of deviation in the fetal heart rate correlated significantly with neonatal neurologic examinations at 0 to 48 hours and 72 hours to 1 week: late decelerations in stage 1 and in stage 2. Other variables from labor and delivery, specifically, duration of labor after hospital admission, failure of labor to progress, number of fetal scalp pH values, and presence of meconium were important predictors of neonatal outcome in the regression analyses. The fetal heart rate deviations did contribute significantly to the percent variance accounted for in the regression analyses with neonatal outcomes of Apgar scores at 1 and 5 minutes and serial neonatal neurologic examinations.

Cesarean section and perinatal outcome: Response from the House of Horne

A direct comparison between Parkland Memorial Hospital in Dallas, Texas, and the National Maternity Hospital in Dublin, Ireland, on the basis of limited numbers taken from one year only (1983) led to the conclusion that the liberal use of cesarean section in Dallas was associated with a sevenfold decrease in intrapartum fetal deaths and a twofold decrease in neonatal seizures. However, when the scope of the survey is extended to include the year before (1982) and the year after (1984), a different picture emerges. During this extended period there were almost four times as many cesarean sections performed in Dallas with no significant difference in overall perinatal mortality, while for two of three years the incidence of neonatal seizures was twice as high in Dallas when compared with Dublin. The fact that high cesarean rates continue to rely on evidence of such a tenuous nature must remain a matter of concern.

Problems in the management of patients with artificial valves during pregnancy

Summary. During the past 15 years, 12 patients with prosthetic valves were treated during 18 pregnancies in the four Dublin maternity hospitals. These patients were on long‐term anticoagulants and their pregnancies were reviewed to assess the problems associated with anticoagulation. One baby had warfarin embryopathy, six pregnancies ended in spontaneous abortions and there were two intrauterine deaths. On the basis of the findings a policy on the most appropriate anticoagulant regimen in such cases was formulated.

Surgical induction of labor

One thousand consecutive cases of surgical induction of labor are presented. The results and complications are summarized. Personal selection, performance, and supervision of patients are important factors in achieving satisfactory results.