Report backs up link between smoking, obesity and stillbirth

17 Jun 2014 | Perinatal & Maternal Mortality Review Committee

A report from the Perinatal and Maternal Mortality Review Committee (PMMRC) has provided further evidence of the link between smoking, obesity and stillbirth.

The PMMRC is responsible for reviewing maternal deaths and all deaths of babies from 20 weeks gestation up to 28 days after birth, or weighing at least 400g if gestation is unknown. It advises the Health Quality & Safety Commission on how to reduce these deaths.

In its annual report released today, the Committee says national maternity data shows a clear link between stillbirth and smoking, and stillbirth and being overweight, backing up the findings in published studies. The data captures maternity information from lead maternity carers and public hospitals. The analysis also showed that women of Indian ethnicity and women having their first baby were at higher risk of stillbirth.

PMMRC Chair Dr Sue Belgrave says the findings show how critical it is to ensure pregnant women receive as much help and support as possible to quit smoking and have a healthy weight both before and during pregnancy.

“Stillbirth is often unexplained, but where we do know how to reduce risk we need to make sure this information is widely available so women have the opportunity to reduce their own risk of stillbirth.

“Every effort must be made to encourage women to take part in smoking cessation programmes before, during and after pregnancy. There are a number of ways that women, including pregnant women, can get help to quit smoking. Further information can be found at Quitline. (The website is available at:

“Likewise, weight loss before pregnancy is recommended for women who are obese and pregnant women should be encouraged to maintain a healthy diet and monitor their weight gain during pregnancy.”

The report found there were 10 maternal deaths in 2012. Two deaths were due to complications of pregnancy and 8 were related to pre-existing diseases or suicide. The maternal mortality rate – the death of a mother while pregnant or up to six weeks after birth – was 16 women in every 100,000 pregnancies. There has been no statistically significant change in the maternal death rate since PMMRC began analysing maternal mortality data in 2006.

The perinatal mortality rate – the death of a baby from 20 weeks gestation up to 28 days after birth – has also remained stable, at 10.7/1000 births. This is equivalent to one baby dying in pregnancy or during the first month of life for every 100 babies born. New Zealand’s perinatal mortality rates are comparable to rates in Australia and the United Kingdom. It is pleasing to note there has been a significant reduction in deaths using the World Health Organization definition of babies weighing more than 1000gm.

Dr Belgrave says there has also been a significant reduction in unexplained stillbirths and deaths of term babies during labour due to lack of oxygen.

“While further research is needed to clarify the reasons for these reductions, this is obviously very good news. The PMMRC has developed a tool to assess each death for contributory factors with a focus on preventing the deaths that we can.

“The reduction in unexplained stillbirths means more parents are being given a reason as to why their baby dies, which helps with the grieving process and planning for future pregnancies.”

Other key report findings

  • The risk of maternal death for women living in most deprived areas is 2.5 times that of those living in the least deprived areas.
  • Maori and Pacific mothers are three times more likely to die while pregnant or up to six weeks after birth than non-Maori, non-Pacific mothers.
  • Maori and Pacific women, women who smoke during pregnancy, women living in poorer areas and women having their first babies are at increased risk of neonatal death of babies born between 20-27 weeks (a baby born alive between 20 to 27 weeks gestation who dies prior to 28 days of life).
  • Women who smoke during pregnancy are at increased risk of neonatal death of babies born from 28 weeks gestation.
  • The incidence of neonatal encephalopathy, a condition usually resulting from lack of oxygen to the brain around the time of birth, is significantly higher among babies of Pacific mothers than among babies of New Zealand European mothers.
  • In 2012, 78 percent of babies with moderate to severe neonatal encephalopathy received induced cooling, to reduce damage related to lack of oxygen.

Report recommendations

The report includes the following recommendations.

Perinatal-related mortality

  • Efforts must be made to encourage women to engage in effective smoking cessation programmes prior to, during and after pregnancy.
  • Initiatives to prevent obesity prior to pregnancy and promote healthy weight gain in pregnancy should be supported.
  • Addressing the impact of poverty requires wider societal commitment as has been highlighted in the recent Health Select Committee report on improving child health outcomes.

Maternal mortality

  • Women who are unstable or clinically unwell should be cared for in the most appropriate place and be under close observation.
  • Women with serious pre-existing medical conditions require a multidisciplinary management plan for the pregnancy, birth and postpartum period.

Neonatal encephalopathy

  • All DHBs should undertake local review of cases of neonatal encephalopathy to identify areas for improvement in care including adequacy of resuscitation and cooling.
  • A guideline for the investigation and management of neonatal encephalopathy should be developed.

The full report can be downloaded below.

Questions & Answers for the Eighth Report are available here.

Last updated 08/07/2014