Aust NZ J Obstet Gynaecol 1992; 32: 4: 309
Perinatal Mortality in a Tertiary Obstetric Institution John R. H. Fliegner, MD, MGO, FRCS(Ed), FRACS, FRCOG, FRACOG The Royal Women’s Hospital and Department of Obstetrics and Gynaecology, University of Melbourne
EDITORIAL COMMENT: Readers may wish to ponder on the remarkably good results achieved in the Royal Women’s Hospital Birth Centre where according to an enquiry made by the Editor electronicfetal heart rate monitoring is not performed. This casts some doubt on the Author’s opinion that the low intrapartum mortality rate reported in this series from the Royal Women’s Hospital is due to fetal heart rate monitoring in labour! Reply from Author: The 2 groups i.e. the Women’sHospital Birth Centre and the Public Hospital patients are in no way comparable. Patients attending the Royal Women’s Hospital Family Birth Centre are a highly selected low risk group. Women with any significant risk factors are excluded e.g. hypertension, antepartum haemorrhage, prolonged pregnancy, low oestriol excretion, abnormal antenatal CTG, decreasedfetal movements, meconium-stained liquor, Syntocinon infusion, slow progress in labour and abnormality on auscultation of the fetal heart in labour. Despite these rigid criteria, there are still a number of asphyxiated babies born in the centre and there have even recently been 2 perinatal deaths. Perhaps this low rate of neonatal asphyxia would have been even lower with intrapartum C E monitoring in these very low risk women.
Summary: At the Royal Women’s Hospital, Melbourne in the 3 years 1987-1989analysis of the records of 13,347 public patients revealed an overall perinatal wastage of 20.8 per 1,000 births. This seemingly high figure resulted from the fact that 45% of losses occurred in nonbooked and emergency admissions. Many patients were referred with major complications of pregnancy, especially gross prematurity, lethal congenital malformations and intrauterine deaths. During the 3-year period 74% of perinatal losses occurred before 33 weeks’ gestation and only 10% were after 37 weeks. By comparison at a Victorian State level, 47% of perinatal deaths occurred before 33 weeks and more than 35% after 37 weeks’ gestation. The major causes of perinatal wastage in both groups were similar. At the Royal Women’s Hospital in the 3-year period lethal congenital abnormalities accounted for 19.1% of fetal wastage, premature labour, premature rupture of the membranes and cervical incompetence 16.2%, multiple pregnancy 14.7’70, antepartum haemorrhage 14.0% and hypertensive disorders 9.7%. During the 3-year period 7.7% of hospital stillbirths were intrapartum compared to 27% for the State of Victoria. The stillbirth rate in Victoria has declined over the past decade, but to a lesser extent than the neonatal death rate. Over the 3-year period 1987-1989 the ratio of stillbirths to neonatal deaths was 3 to 2, and in 1989 there were nearly twice as many stillbirths as neonatal deaths (424 versus 240). Furthermore, 55% of stillborn infants in Victoria had birth-weights of more than 1,500 g compared to the Royal Women’s Hospital figure of 36%. It is clear that future improvement in perinatal mortality rate must be aimed at the prevention of stillbirths in mature pregnancies. With the sharp decline in maternal and perinatal mortality there is increased complacency about the safety of childbirth. Nothing less than an uncomplicated confinement and a perfectly healthy baby is Address for correspondence: Associate Professor J.R.H. Fliegner, Royal Women’s Hospital, 132 Grattan Street, Carlton, Victoria, 3053.
expected. Unfortunately, this is not always the case. Potentially avoidable factors resulting from deficiencies in antenatal and intrapartum care continue to be highlighted in the annual reports of the Consultative Council on Obstetric and Paediatric Mortality and Morbidity (1-4). In perinatal medicine, it is important to review results of patient care and this is generally accomplished by consideration of mortality and morbidity statistics at
AUST.AND N.Z. JOURNAL OF OBSTETRICS AND GYNAECOWGY
310
Table 1. Perinatal Mortality in Public Hospital Patients at the Royal Women’s Hospital, Melbourne, 1987-1989. Comparative Outcome Between Booked and Nonbooked and Emergency Births
a hospital, State and national basis. This allows significant problems to be addressed. Plans can then be made to employ resources in areas that are important and in which tangible further improvement can take place. The current prospective study was undertaken with these factors in mind. It involved a prospective 3-year study of the causative factors in perinatal mortality at the Royal Women’s Hospital, Melbourne, Australia compared to the overall perinatal statistics for the State of Victoria.
Year
Babies Stillbirths Neonatal Total Perinatal born deaths wastage per 1,000 total births
~~~~
~
~~~
~
4,161 4,583 4,603 13,347 11,429 (86%) 1,918 Nonbooked and emergency (14%) admissions 1987 1988 1989 Total Booked
MATERIALS AND METHODS At the Royal Women’s Hospital monthly perinatal mortality and morbidity audits are conducted by the senior obstetric and paediatric staff. Analysis of the perinatal wastage in all public patients delivered between 1987 and 1989 was undertaken. In particular, comparison was made between perinatal wastage in booked and emergency admissions. The principal causes of perinatal losses were analyzed with particular emphasis on the gestational age at which this occurred, and whether avoidable factors were present. A comparison was made between the perinatal wastage at the Royal Women’s Hospital and the State of Victoria over the 3-year period. Comparison was made between the causative factors, birth-weights, gestation at which losses occurred, and the incidence of intrapartum fetal wastage. The definition of perinatal death differs slightly at a hospital and State level. In Victoria the following definitions apply for the purposes of the annual report. A stillborn child is one weighing at least 500 g or, if the weight is not known born after at least 22 weeks’ gestation. A neonatal death is death within 28 days of birth of an infant whose birth-weight was at least 500 g or, if the weight is not known, an infant born after at least 22 weeks’ gestation. The perinatal mortality rate is the number of perinatal deaths (stillbirths and neonatal deaths) per 1,000 births (live and still).
~
70 57 54 181 99
31 32 34 97 53
101 89 88 278 152
24.3 19.4 19.1 20.8 13.3
82
44
126
65.7
In Royal Women’s Hospital statistics perinatal death refers to a death of an infant weighing 400 g or more, or after a gestation of 20 weeks or more. However, for purposes of comparison with State figures perinatal deaths of babies weighing less than 500 g were not included in the study.
RESULTS The overall results are tabulated in tables 1-5. At the Royal Women’s Hospital in the 3-year period 1987-1989 a total of 13,347 births occurred in the public sector. However there were 28 births in which the gestation was either between 20 and 22 weeks, or the birth-weight less than 500 g. These were therefore eliminated from the comparative statistics. The overall perinatal wastage of 278 (181 stillbirths and 97 neonatal deaths) from 13,347 births represented a mortality rate of 20.8 per 1,000births (table 1). There were 152 deaths in 11,429 births in booked antenatal patients - a perinatal wastage of 13.3 per 1,000 births. The 126 deaths resulting from nonbooked and emergency admissions represented a perinatal wastage of 65.7 per 1,000 births.
Table 2. Gestational Age and Principal Cause of Death in 278 Perinatal Deaths at the Royal Women’s Hospital, 1987-1989 Gestational age (weeks) Cause of death Lethal congenital abnormalities Premature labour, premature rupture of membranes, cervical incompetence and intrauterine sepsis Multiple pregnancy Antepartum haemorrhage Hypertension, preeclampsia and renal disease Idiopathic placental insufficiency Cord accidents Diabetes Erythroblastosis Intrapartum deaths (and mechanical factors) Maternal disease Miscellaneous Unexdained
28-32
24
14
6
53
19.1
34 23 20 16
8 12 14 6 2 2
-
45 41 39 27 6 7 5 5 14
16.2 14.7 14.0 9.1 2.2 2.5 1.8 1.8 5 .O 4.0 1.8 7.2
1
-
1 1 3 5 2 6
136 (48.9%)
33-36
37-40
>40
TO
40
136 71 43 26 2
48.9 25.5 15.5 9.4 0.7
Total
278
Gestation (weeks)
Victoria Number 556 410 347 611 112
%
27.3 20.1 17.0 30.0 5.5
2,036
Table 4. Comparison of Stillbirth and Neonatal Mortality Data Between the Royal Women’s Hospital and Victoria (1987-1989) in Terms of Birth-Weight and Deaths During Labour Royal Women’s Hospital Number Stillbirths (total) 181 Birth-weight of stillbirths 1,5OOg 65 Intraparturn 14 deaths Neonatal deaths (total) 97 Birth-weight of neonatal deaths < 1,500 g 74 > 1,500 g 23 Total perinatal deaths
278
Vo
Victoria Number
Yo
1,225 (64.1) (35.9)
556 669
(45.4) (54.6)
(7.7)
327
(26.7)
811 (76.3) (23.7)
393 418
(48.5) (51.5)
2,036
Of the 126 nonbooked perinatal deaths 27 occurred in patients referred with premature rupture of the membranes or in premature labour, 24 resulted from lethal congenital malformations, 16 followed severe medical complications of pregnancy, and 13 were referred with intrauterine deaths. Thus 80 (63%) of nonbooked perinatal losses occurred in patients who were referred to the hospital with an already poor or hopeless prognosis. Table 2 lists the principal causes of death in 278 perinatal losses at the Royal Women’s Hospital, and the gestational age at which this occurred. Lethal congenital abnormalities accounted for 19.1%, premature rupture of the membranes and cervical incompetence 16.2%, multiple pregnancy 14.7%’ antepartum haemorrhage 14.0%, and hypertensive disorders 9.7%; 207 of the 278 perinatal deaths (75%) occurred before 33 weeks’ gestation. There were 28 fetal losses (10.1%) after 37 weeks’ gestation, and only 2 deaths occurred beyond 40 weeks. In Table 3 a comparison is made between the gestation at delivery of the perinatal deaths at the Royal Women’s Hospital and the perinatal deaths in the State of Victoria over the same period 1987-1989. In Victoria 47% of perinatal losses occurred before 33 weeks’ gestation and 53% occurred after this time. Of the 2,036 perinatal losses 611 (30%) occurred between 37 and 40 weeks, and 112 (5.5%) occurred after 40 weeks’ gestation. By contrast at the Royal Women’s Hospital only 10.1% of perinatal deaths occurred after 37 weeks’ gestation and only 0.7% of perinatal deaths were postterm.
311
Table 5. Family Birth Unit, Royal Women’s Hospital 1980-1989 Booked FBU Antenatal transfers (including 17 FDIU - 1.9%) Commenced labour FBU Intraparturn transfers Confined in FBU Perinatal wastage
5,365 889 4,476 862 3,614 4
(16.6%) (83.4%) (16.1%) (0.089%)
FDIU = Fetal death in utero; FBU = Family Birth Unit
Table 4 analyzes the birth-weights of the stillbirths and neonatal deaths occurring at the Royal Women’s Hospital and in the State of Victoria over the 3-year period. At the hospital 64% of intrauterine deaths weighed less than 1,500 g, and 36% weighed more than 1,500 g. By comparison in the State of Victoria 45% of stillbirths weighed less than 1,500 g and 55% greater than 1,500 g. The same trend emerged in relation to neonatal deaths. At the Royal Women’s Hospital 76% of neonatal deaths weighed less than 1,500 g and only 24% weighed more than 1,500 g. In Victoria 48% of neonatal deaths weighed less than 1,500 g and 52% weighed more than 1,500g. Thus at a State level 53.5% (1,087 of 2,036) of perinatal deaths were infants with birth-weights more than 1,500 g, compared with 31.7% (88 of 278) at the Royal Women’s Hospital. Table 5 shows the statistics of the Family Birth Centre at the Royal Women’s Hospital in the 10-year period 1980-1989. Of 5,365 patients who were originally booked 889 were transferred antenatally (16.6%). This included 17 patients (1.9%) in which fetal death in utero had occurred. Of the 4,476 patients who commenced labour in the Family Birth Unit, 3,614 (81%) were confined there without perinatal wastage. There were 862 intrapartum transfers because of complications, and 4 perinatal deaths resulted. Two patients had a fetal death in utero on presenting in labour. One patient sustained a severe placental abruption leading to fetal demise. The fourth death was a neonatal death due to trisomy 13. Thus although there were no perinatal deaths in patients who were actually confined in the Family Birth Unit at the hospital there were 4 perinatal deaths among those who commenced labour in the Unit - a perinatal mortality rate of 0.89 per 1,000.
DISCUSSION There is a continuing controversy about the preferred venue of childbirth. Should it be in a traditional labour ward, in a birthing centre within a hospital setting or at home? The current study was undertaken to analyze the perinatal statistics at the Royal Women’s Hospital, Melbourne and compare them with the overall Victorian statistics, Comparison was also made with the Birthing Unit of the hospital. The latter deal with spontaneous normal delivery of low-risk mothers. Should complications ensue such patients are then transferred to the general hospital labour ward for management. In the 3-year period the perinatal wastage at the Royal Women’s Hospital was 20.8 per 1,000 births. However,
312
OF OBSTETRICS AUST.AND N.Z. JOURNAL
this high figure is largely due to external factors. These include referral of babies with lethal congenital malformations, intrauterine death, and mothers either in premature labour or with severe medical complications. In booked public hospital patients the perinatal wastage was 13.3 per 1,000 births. This is higher than the Victorian figures (11.0 in 1987, 10.9 in 1988, and 10.4 in 1989). Being a specialist centre the hospital has a core of high-risk patients with recurrent obstetrical medical and social problems. In the Family Birth Unit at the hospital the perinatal mortality rate was 0.89 per 1,000 births in patients who actually began labour in the unit. At the hospital all perinatal deaths are discussed in detail by the obstetric and paediatric staff. It is becoming less common for preventable causes to be identified either in late pregnancy or in labour at such hospital meetings. In the 3-year period 10.1% of deaths occurred after 37 weeks’ gestation, and there were only 2 deaths after 40 weeks (0.7%). Midpregnancy fetal wastage remains a continuing challenge and is highlighted in the present report. At the Royal Women’s Hospital 136 of the 278 perinatal deaths (49%) occurred before 28 weeks’ gestation. Apart from lethal congenital malformations, extreme prematurity and intrauterine hypoxia associated with premature rupture of the membranes, cervical incompetence, idiopathic premature labour, multiple pregnancy, antepartum haemorrhage and hypertensive disorders were the principal causes of death. The problem of midpregnancy fetal wastage associated with these factors has previously been reported in detail (5). At the Royal Women’s Hospital the birth-weight was more than 1,500 g in 36% of intrauterine deaths. By comparison in Victoria in 55% of intrauterine deaths birth-weight was more than 1,500 g and 36% occurred after 37 weeks. Postterm losses made up 5.5% and 26.7% of stillbirths overall were intrapartum deaths. However at the hospital only 7.7% of deaths occurred intrapartum. The author believes that the widespread use of electronic fetal monitoring in labour at the Royal Women’s
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Hospital is responsible for the low incidence of intrapartum deaths in pregnancy. Currently over 52% of patients at the hospitals are monitored during labour. It is always employed for high-risk and postterm pregnancies and where there is meconium-staining of the liquor amnii. It may be that in some instances because of the absence of electronic fetal monitoring in peripheral centres, some patients are judged to have an intrapartum death when in fact fetal death has occurred before the onset of labour. However, this is unlikely to explain the almost 4-fold increase in the proportion of perinatal deaths that occur intrapartum in Victoria compared with that at the Royal Women’s Hospital. There is no doubt that at a State level many cases of intrapartum stillbirths are associated with either a lack of monitoring or failure to recognize clinical warning signals. The added tragedy is that these babies are externally normal and usually not growth retarded. A comparison of neonatal deaths occurring at the Royal Women’s Hospital and in Victoria at large shows a similar trend to that of stillbirths. At the hospital birthweight was more than 1,500 g in only 24% of neonatal deaths compared with 52% in the State of Victoria (table 4).
Ackn owledgernents The author wishes to acknowledge the cooperation of the Medical Records Department and the senior medical staff of the Royal Women’s Hospital, Melbourne for their cooperation in providing access to the data presented. I wish to thank Miss Maria Fiorenza for typing the manuscript. References 1. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1986. 2. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1987. 3. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1988. 4. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1989. 5. Fliegner JR. Can Anything Be Done About Mid-Trimester Fetal Wastage? Occasional Review. Aust. NZ J Obstet Gynaecol 1987; 27: 205-210.
Perinatal Mortality in a Tertiary Obstetric Institution John R. H. Fliegner, MD, MGO, FRCS(Ed), FRACS, FRCOG, FRACOG The Royal Women’s Hospital and Department of Obstetrics and Gynaecology, University of Melbourne
EDITORIAL COMMENT: Readers may wish to ponder on the remarkably good results achieved in the Royal Women’s Hospital Birth Centre where according to an enquiry made by the Editor electronicfetal heart rate monitoring is not performed. This casts some doubt on the Author’s opinion that the low intrapartum mortality rate reported in this series from the Royal Women’s Hospital is due to fetal heart rate monitoring in labour! Reply from Author: The 2 groups i.e. the Women’sHospital Birth Centre and the Public Hospital patients are in no way comparable. Patients attending the Royal Women’s Hospital Family Birth Centre are a highly selected low risk group. Women with any significant risk factors are excluded e.g. hypertension, antepartum haemorrhage, prolonged pregnancy, low oestriol excretion, abnormal antenatal CTG, decreasedfetal movements, meconium-stained liquor, Syntocinon infusion, slow progress in labour and abnormality on auscultation of the fetal heart in labour. Despite these rigid criteria, there are still a number of asphyxiated babies born in the centre and there have even recently been 2 perinatal deaths. Perhaps this low rate of neonatal asphyxia would have been even lower with intrapartum C E monitoring in these very low risk women.
Summary: At the Royal Women’s Hospital, Melbourne in the 3 years 1987-1989analysis of the records of 13,347 public patients revealed an overall perinatal wastage of 20.8 per 1,000 births. This seemingly high figure resulted from the fact that 45% of losses occurred in nonbooked and emergency admissions. Many patients were referred with major complications of pregnancy, especially gross prematurity, lethal congenital malformations and intrauterine deaths. During the 3-year period 74% of perinatal losses occurred before 33 weeks’ gestation and only 10% were after 37 weeks. By comparison at a Victorian State level, 47% of perinatal deaths occurred before 33 weeks and more than 35% after 37 weeks’ gestation. The major causes of perinatal wastage in both groups were similar. At the Royal Women’s Hospital in the 3-year period lethal congenital abnormalities accounted for 19.1% of fetal wastage, premature labour, premature rupture of the membranes and cervical incompetence 16.2%, multiple pregnancy 14.7’70, antepartum haemorrhage 14.0% and hypertensive disorders 9.7%. During the 3-year period 7.7% of hospital stillbirths were intrapartum compared to 27% for the State of Victoria. The stillbirth rate in Victoria has declined over the past decade, but to a lesser extent than the neonatal death rate. Over the 3-year period 1987-1989 the ratio of stillbirths to neonatal deaths was 3 to 2, and in 1989 there were nearly twice as many stillbirths as neonatal deaths (424 versus 240). Furthermore, 55% of stillborn infants in Victoria had birth-weights of more than 1,500 g compared to the Royal Women’s Hospital figure of 36%. It is clear that future improvement in perinatal mortality rate must be aimed at the prevention of stillbirths in mature pregnancies. With the sharp decline in maternal and perinatal mortality there is increased complacency about the safety of childbirth. Nothing less than an uncomplicated confinement and a perfectly healthy baby is Address for correspondence: Associate Professor J.R.H. Fliegner, Royal Women’s Hospital, 132 Grattan Street, Carlton, Victoria, 3053.
expected. Unfortunately, this is not always the case. Potentially avoidable factors resulting from deficiencies in antenatal and intrapartum care continue to be highlighted in the annual reports of the Consultative Council on Obstetric and Paediatric Mortality and Morbidity (1-4). In perinatal medicine, it is important to review results of patient care and this is generally accomplished by consideration of mortality and morbidity statistics at
AUST.AND N.Z. JOURNAL OF OBSTETRICS AND GYNAECOWGY
310
Table 1. Perinatal Mortality in Public Hospital Patients at the Royal Women’s Hospital, Melbourne, 1987-1989. Comparative Outcome Between Booked and Nonbooked and Emergency Births
a hospital, State and national basis. This allows significant problems to be addressed. Plans can then be made to employ resources in areas that are important and in which tangible further improvement can take place. The current prospective study was undertaken with these factors in mind. It involved a prospective 3-year study of the causative factors in perinatal mortality at the Royal Women’s Hospital, Melbourne, Australia compared to the overall perinatal statistics for the State of Victoria.
Year
Babies Stillbirths Neonatal Total Perinatal born deaths wastage per 1,000 total births
~~~~
~
~~~
~
4,161 4,583 4,603 13,347 11,429 (86%) 1,918 Nonbooked and emergency (14%) admissions 1987 1988 1989 Total Booked
MATERIALS AND METHODS At the Royal Women’s Hospital monthly perinatal mortality and morbidity audits are conducted by the senior obstetric and paediatric staff. Analysis of the perinatal wastage in all public patients delivered between 1987 and 1989 was undertaken. In particular, comparison was made between perinatal wastage in booked and emergency admissions. The principal causes of perinatal losses were analyzed with particular emphasis on the gestational age at which this occurred, and whether avoidable factors were present. A comparison was made between the perinatal wastage at the Royal Women’s Hospital and the State of Victoria over the 3-year period. Comparison was made between the causative factors, birth-weights, gestation at which losses occurred, and the incidence of intrapartum fetal wastage. The definition of perinatal death differs slightly at a hospital and State level. In Victoria the following definitions apply for the purposes of the annual report. A stillborn child is one weighing at least 500 g or, if the weight is not known born after at least 22 weeks’ gestation. A neonatal death is death within 28 days of birth of an infant whose birth-weight was at least 500 g or, if the weight is not known, an infant born after at least 22 weeks’ gestation. The perinatal mortality rate is the number of perinatal deaths (stillbirths and neonatal deaths) per 1,000 births (live and still).
~
70 57 54 181 99
31 32 34 97 53
101 89 88 278 152
24.3 19.4 19.1 20.8 13.3
82
44
126
65.7
In Royal Women’s Hospital statistics perinatal death refers to a death of an infant weighing 400 g or more, or after a gestation of 20 weeks or more. However, for purposes of comparison with State figures perinatal deaths of babies weighing less than 500 g were not included in the study.
RESULTS The overall results are tabulated in tables 1-5. At the Royal Women’s Hospital in the 3-year period 1987-1989 a total of 13,347 births occurred in the public sector. However there were 28 births in which the gestation was either between 20 and 22 weeks, or the birth-weight less than 500 g. These were therefore eliminated from the comparative statistics. The overall perinatal wastage of 278 (181 stillbirths and 97 neonatal deaths) from 13,347 births represented a mortality rate of 20.8 per 1,000births (table 1). There were 152 deaths in 11,429 births in booked antenatal patients - a perinatal wastage of 13.3 per 1,000 births. The 126 deaths resulting from nonbooked and emergency admissions represented a perinatal wastage of 65.7 per 1,000 births.
Table 2. Gestational Age and Principal Cause of Death in 278 Perinatal Deaths at the Royal Women’s Hospital, 1987-1989 Gestational age (weeks) Cause of death Lethal congenital abnormalities Premature labour, premature rupture of membranes, cervical incompetence and intrauterine sepsis Multiple pregnancy Antepartum haemorrhage Hypertension, preeclampsia and renal disease Idiopathic placental insufficiency Cord accidents Diabetes Erythroblastosis Intrapartum deaths (and mechanical factors) Maternal disease Miscellaneous Unexdained
28-32
24
14
6
53
19.1
34 23 20 16
8 12 14 6 2 2
-
45 41 39 27 6 7 5 5 14
16.2 14.7 14.0 9.1 2.2 2.5 1.8 1.8 5 .O 4.0 1.8 7.2
1
-
1 1 3 5 2 6
136 (48.9%)
33-36
37-40
>40
TO
40
136 71 43 26 2
48.9 25.5 15.5 9.4 0.7
Total
278
Gestation (weeks)
Victoria Number 556 410 347 611 112
%
27.3 20.1 17.0 30.0 5.5
2,036
Table 4. Comparison of Stillbirth and Neonatal Mortality Data Between the Royal Women’s Hospital and Victoria (1987-1989) in Terms of Birth-Weight and Deaths During Labour Royal Women’s Hospital Number Stillbirths (total) 181 Birth-weight of stillbirths 1,5OOg 65 Intraparturn 14 deaths Neonatal deaths (total) 97 Birth-weight of neonatal deaths < 1,500 g 74 > 1,500 g 23 Total perinatal deaths
278
Vo
Victoria Number
Yo
1,225 (64.1) (35.9)
556 669
(45.4) (54.6)
(7.7)
327
(26.7)
811 (76.3) (23.7)
393 418
(48.5) (51.5)
2,036
Of the 126 nonbooked perinatal deaths 27 occurred in patients referred with premature rupture of the membranes or in premature labour, 24 resulted from lethal congenital malformations, 16 followed severe medical complications of pregnancy, and 13 were referred with intrauterine deaths. Thus 80 (63%) of nonbooked perinatal losses occurred in patients who were referred to the hospital with an already poor or hopeless prognosis. Table 2 lists the principal causes of death in 278 perinatal losses at the Royal Women’s Hospital, and the gestational age at which this occurred. Lethal congenital abnormalities accounted for 19.1%, premature rupture of the membranes and cervical incompetence 16.2%, multiple pregnancy 14.7%’ antepartum haemorrhage 14.0%, and hypertensive disorders 9.7%; 207 of the 278 perinatal deaths (75%) occurred before 33 weeks’ gestation. There were 28 fetal losses (10.1%) after 37 weeks’ gestation, and only 2 deaths occurred beyond 40 weeks. In Table 3 a comparison is made between the gestation at delivery of the perinatal deaths at the Royal Women’s Hospital and the perinatal deaths in the State of Victoria over the same period 1987-1989. In Victoria 47% of perinatal losses occurred before 33 weeks’ gestation and 53% occurred after this time. Of the 2,036 perinatal losses 611 (30%) occurred between 37 and 40 weeks, and 112 (5.5%) occurred after 40 weeks’ gestation. By contrast at the Royal Women’s Hospital only 10.1% of perinatal deaths occurred after 37 weeks’ gestation and only 0.7% of perinatal deaths were postterm.
311
Table 5. Family Birth Unit, Royal Women’s Hospital 1980-1989 Booked FBU Antenatal transfers (including 17 FDIU - 1.9%) Commenced labour FBU Intraparturn transfers Confined in FBU Perinatal wastage
5,365 889 4,476 862 3,614 4
(16.6%) (83.4%) (16.1%) (0.089%)
FDIU = Fetal death in utero; FBU = Family Birth Unit
Table 4 analyzes the birth-weights of the stillbirths and neonatal deaths occurring at the Royal Women’s Hospital and in the State of Victoria over the 3-year period. At the hospital 64% of intrauterine deaths weighed less than 1,500 g, and 36% weighed more than 1,500 g. By comparison in the State of Victoria 45% of stillbirths weighed less than 1,500 g and 55% greater than 1,500 g. The same trend emerged in relation to neonatal deaths. At the Royal Women’s Hospital 76% of neonatal deaths weighed less than 1,500 g and only 24% weighed more than 1,500 g. In Victoria 48% of neonatal deaths weighed less than 1,500 g and 52% weighed more than 1,500g. Thus at a State level 53.5% (1,087 of 2,036) of perinatal deaths were infants with birth-weights more than 1,500 g, compared with 31.7% (88 of 278) at the Royal Women’s Hospital. Table 5 shows the statistics of the Family Birth Centre at the Royal Women’s Hospital in the 10-year period 1980-1989. Of 5,365 patients who were originally booked 889 were transferred antenatally (16.6%). This included 17 patients (1.9%) in which fetal death in utero had occurred. Of the 4,476 patients who commenced labour in the Family Birth Unit, 3,614 (81%) were confined there without perinatal wastage. There were 862 intrapartum transfers because of complications, and 4 perinatal deaths resulted. Two patients had a fetal death in utero on presenting in labour. One patient sustained a severe placental abruption leading to fetal demise. The fourth death was a neonatal death due to trisomy 13. Thus although there were no perinatal deaths in patients who were actually confined in the Family Birth Unit at the hospital there were 4 perinatal deaths among those who commenced labour in the Unit - a perinatal mortality rate of 0.89 per 1,000.
DISCUSSION There is a continuing controversy about the preferred venue of childbirth. Should it be in a traditional labour ward, in a birthing centre within a hospital setting or at home? The current study was undertaken to analyze the perinatal statistics at the Royal Women’s Hospital, Melbourne and compare them with the overall Victorian statistics, Comparison was also made with the Birthing Unit of the hospital. The latter deal with spontaneous normal delivery of low-risk mothers. Should complications ensue such patients are then transferred to the general hospital labour ward for management. In the 3-year period the perinatal wastage at the Royal Women’s Hospital was 20.8 per 1,000 births. However,
312
OF OBSTETRICS AUST.AND N.Z. JOURNAL
this high figure is largely due to external factors. These include referral of babies with lethal congenital malformations, intrauterine death, and mothers either in premature labour or with severe medical complications. In booked public hospital patients the perinatal wastage was 13.3 per 1,000 births. This is higher than the Victorian figures (11.0 in 1987, 10.9 in 1988, and 10.4 in 1989). Being a specialist centre the hospital has a core of high-risk patients with recurrent obstetrical medical and social problems. In the Family Birth Unit at the hospital the perinatal mortality rate was 0.89 per 1,000 births in patients who actually began labour in the unit. At the hospital all perinatal deaths are discussed in detail by the obstetric and paediatric staff. It is becoming less common for preventable causes to be identified either in late pregnancy or in labour at such hospital meetings. In the 3-year period 10.1% of deaths occurred after 37 weeks’ gestation, and there were only 2 deaths after 40 weeks (0.7%). Midpregnancy fetal wastage remains a continuing challenge and is highlighted in the present report. At the Royal Women’s Hospital 136 of the 278 perinatal deaths (49%) occurred before 28 weeks’ gestation. Apart from lethal congenital malformations, extreme prematurity and intrauterine hypoxia associated with premature rupture of the membranes, cervical incompetence, idiopathic premature labour, multiple pregnancy, antepartum haemorrhage and hypertensive disorders were the principal causes of death. The problem of midpregnancy fetal wastage associated with these factors has previously been reported in detail (5). At the Royal Women’s Hospital the birth-weight was more than 1,500 g in 36% of intrauterine deaths. By comparison in Victoria in 55% of intrauterine deaths birth-weight was more than 1,500 g and 36% occurred after 37 weeks. Postterm losses made up 5.5% and 26.7% of stillbirths overall were intrapartum deaths. However at the hospital only 7.7% of deaths occurred intrapartum. The author believes that the widespread use of electronic fetal monitoring in labour at the Royal Women’s
AND
GYNAECOLOGY
Hospital is responsible for the low incidence of intrapartum deaths in pregnancy. Currently over 52% of patients at the hospitals are monitored during labour. It is always employed for high-risk and postterm pregnancies and where there is meconium-staining of the liquor amnii. It may be that in some instances because of the absence of electronic fetal monitoring in peripheral centres, some patients are judged to have an intrapartum death when in fact fetal death has occurred before the onset of labour. However, this is unlikely to explain the almost 4-fold increase in the proportion of perinatal deaths that occur intrapartum in Victoria compared with that at the Royal Women’s Hospital. There is no doubt that at a State level many cases of intrapartum stillbirths are associated with either a lack of monitoring or failure to recognize clinical warning signals. The added tragedy is that these babies are externally normal and usually not growth retarded. A comparison of neonatal deaths occurring at the Royal Women’s Hospital and in Victoria at large shows a similar trend to that of stillbirths. At the hospital birthweight was more than 1,500 g in only 24% of neonatal deaths compared with 52% in the State of Victoria (table 4).
Ackn owledgernents The author wishes to acknowledge the cooperation of the Medical Records Department and the senior medical staff of the Royal Women’s Hospital, Melbourne for their cooperation in providing access to the data presented. I wish to thank Miss Maria Fiorenza for typing the manuscript. References 1. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1986. 2. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1987. 3. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1988. 4. The Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Annual Report for the year 1989. 5. Fliegner JR. Can Anything Be Done About Mid-Trimester Fetal Wastage? Occasional Review. Aust. NZ J Obstet Gynaecol 1987; 27: 205-210.
