Report of the Maternal, Perinatal and Infant Mortality Committee on maternal, perinatal and post-neonatal deaths in 2009 including the South Australian Protocol for Investigation of Stillbirths
Summary
This is the Twenty-fourth Annual Report of the Maternal, Perinatal and Infant Mortality Committee, for the year 2009:
1. There was one direct, one indirect, and one incidental maternal death in 2009. The maternal mortality ratio for the last four-year period 2006-2009 was 6.5 deaths per 100,000 women who gave birth, which is low by international standards. It is also lower than in the preceding five-year period where there were 9.1 deaths per 100,000 women. The overall number of deaths was small (five in four years
compared with eight in five years).
2. The Committee reviewed the 189 perinatal deaths of babies born in South Australia in 2009. The perinatal mortality rate for all births (stillbirths of at least 400g or 20 weeks gestation and all live births) was 9.5 per 1,000 births. The stillbirth rate was 7.0 per 1,000 births and the neonatal mortality rate 2.5 per 1,000 live births. Over the past years, declines have occurred particularly in the perinatal mortality rate used for international comparison, i.e. stillbirth and death within the first 7 days of life for babies weighing at least 1,000g. The early neonatal death rate for international comparison remained low in 2009 at 0.9 per 1,000 live births.
3 Eighty-three percent of the perinatal deaths occurred in preterm babies (less than 37 weeks gestation). The leading cause of perinatal death in 2009 was again congenital abnormalities, which accounted for 34% of the deaths. Other leading causes were spontaneous preterm birth (11%), specific perinatal conditions (11%) and stillbirth of unknown cause (11%). There were 21 stillbirths of unknown cause, a rate of 1.1 per 1,000 births in 2009. This rate has fallen in recent years, compared with 2.0 per 1,000 births in 1995-1998. The Committee has distributed its protocol for the investigation of stillbirths to all obstetric units (Appendix 8). Twenty-one deaths were attributed to preterm birth. Preterm birth and poor fetal growth (which contributed 9% of deaths) have been associated with smoking during pregnancy. The proportion of women smoking during pregnancy has been declining in the state. However, in 2009 it remained at 16%.
4. Nine babies of Aboriginal mothers died during the perinatal period. The perinatal mortality rate of 14.6 per 1,000 births with Aboriginal mothers in 2009 was the second lowest recorded, but remained higher than that of 9.3 per 1,000 with non-Aboriginal mothers. The rates of preterm, small-for-gestational-age and low birthweight births with Aboriginal mothers also remained higher. The proportion of Aboriginal women who smoked during pregnancy was 52% compared with 16% for non-Aboriginal women.
5. The Committee also reviewed the 23 post-neonatal deaths in 2009 of babies born in South Australia, two of which were the babies of Aboriginal mothers. The postneonatal mortality rate remained very low at 1.2 per 1,000 live births. Congenital abnormalities accounted for 11 (48%) post-neonatal deaths. There were 10 ‘Sudden Unexpected Deaths in Infancy’ (SUDIs). Three subcategories of the SUDI deaths can be difficult to distinguish: ‘SIDS’, ‘accidental asphyxiation’ and ‘undetermined cause’. In total, six deaths, including one SIDS death, were attributed to these three subcategories.
6. The infant mortality rate in 2009 was 3.6 per 1,000 live births. The infant mortality rate for babies of Aboriginal mothers of 4.9 per 1,000 live births was the lowest recorded but remained higher than that of 3.6 for babies of non-Aboriginal mothers.
7. From the review of maternal, perinatal and post-neonatal deaths, the Committee makes the following recommendations:
General
>> NEW - There should be further development and evaluation of culturally appropriate programs to enhance access to, and uptake of antenatal, birthing and postnatal care in Aboriginal communities.
Antenatal
>> Caring for pregnant women should be undertaken in a setting which is appropriate for the level of risk the pregnancy presents for the mother and/or the baby.
>>Women with current or previous serious medical conditions should be reviewed by a physician early in pregnancy.
>> Pregnant women travelling in motor vehicles need to wear seat belts at all times for safety.
>> Pregnant women with a Body Mass Index (BMI) greater than 35 kg/m2 are at higher risk from anaesthesia. A timely referral for an anaesthetic consultation should be considered for women with a high BMI. South Australia is developing a policy for care of bariatric patients.
>> Effective strategies should be pursued to reduce smoking in pregnancy, including culturally appropriate smoking cessation interventions for Aboriginal women.
>> Testing the antibody status of Rhesus D negative women before the first administration of Anti-D is important. A measurable titre of Anti-D antibodies is an indicator of potential alloimmunisation and always requires investigation and a specialist opinion.
>> Early ultrasound determination of chorionicity is advised for twin pregnancies, followed by further surveillance for twin-twin transfusion in monochorionic pregnancies.
>> It is satisfying that the decline in deaths attributed to fetal growth restriction has continued from 7.9% of deaths in 2008 to 7.4% in 2009, compared with 11.2% in 2007. Vigilance to ensure that fetal growth restriction is not missed remains warranted.
>> The institution of streamlined arrangements between rural/level 4 hospitals and their regional level 5/6 maternity service in situations where there is a lack of on-site CTG expertise; this includes easier access of rural practitioners to the consultant on call.
Labour and birth>> NEW - All home births should be conducted in accordance with the ‘Policy for Planned Birth at Home in South Australia’; specifically that the mother should be transferred for hospital care when a planned home birth is complicated by the presence of meconium stained liquor.
>> A previous caesarean section and breech presentation are contraindications for home birth.
>>When induction of labour is deemed necessary in the presence of a uterine scar and an unripe cervix, careful consideration should be given to alternative options such as postponing the induction or caesarean section.
>> Once a decision to perform an emergency caesarean section has been made, it is recommended that fetal monitoring should continue until the commencement of surgery.
>>When feto-maternal haemorrhage is suspected, flow cytometry should be considered to estimate the volume as it is more precise than the Kleihauer test.
>> Carriers of Group B Streptococcus and women with risk factors such as prolonged rupture of membranes require appropriate screening and antibiotic treatment.
Postnatal>> NEW - Where a woman presents with serious medical complications early in the post partum period she should be reviewed by a physician with an interest in obstetrics, if available, as well as by an obstetrician, together with other medical specialists as appropriate.
>> If a diagnosis of pre-eclampsia has been made, the blood pressure should be monitored until it has settled and any abnormalities of renal or liver function or blood counts have been appropriately managed.
>> Non-steroidal anti-inflammatory drugs should be avoided post-partum and post-operatively in women with pre-eclampsia. Low dose aspirin, especially when commenced early in pregnancy, remains an effective drug for prevention of pre-eclampsia.
>> Use of the recently-revised protocol for investigating stillbirths, which has been sent to all maternity units in South Australia (Appendix 8).
>> Seeking parental permission for autopsy, which may provide information most valuable in the counselling of parents and in the management of future pregnancies. The State Perinatal Autopsy Service (telephone 08-8161-7333) is available at no cost to the parents, including those in country areas. Certain categories of death have to be reported to the State Coroner (see page 40).
>> Sending placentas for histological examination with all relevant clinical information in all cases of perinatal death (see Appendix 9).
Professional
>> Appropriate training and maintenance of competence in cardiotocograph (CTG) interpretation for all levels of medical and midwifery staff.
>> Ongoing development and implementation of statewide perinatal protocols is recommended (
www.health.sa.gov.au/ppg).
Infant
>> An effective system of appropriate and ongoing support, supervision and referral should be offered to families with known risk factors for adverse child outcome, such as substance abuse, psychiatric illness, extreme youth of the mother or violence in the household. This should be continued at least throughout the first year of life, if not for a longer period of time.
>> Monitoring growth in children, which can be undertaken using the weight percentiles in the child’s Personal Health Record (Blue Book), and investigating why a child is not thriving.
>> Immunisation of children to prevent infectious disease.
>> Vigilance to ensure that potential hazards in the home are removed from the infant’s environment.
>> Vigilance to ensure safe feeding in children under four years of age. Foods that can break off into pieces should not be given, as accidental asphyxiation may occur.
>> Consideration should be given to better ways of identifying serious underlying illness in children presenting to clinicians, for example, Medic Alert bracelets.
>> Systems to facilitate referral by community nurses of high-risk children to paediatricians or tertiary hospitals for urgent appointments need to be considered.
>> Hospitals with high paediatric throughput need provision of 24 hour paediatric expertise.