Severe Illness in Pregnant Women: We must do better!

February 2019

In the US, preventable medical error1 is the third biggest killer behind heart disease and cancer. A 2016 study by Johns Hopkins University calculated that more than 250,000 deaths per year in the US are due to medical error.

In a New Zealand study published in 2006, Auckland University School of Population health lecturers Mary Seddon and Alan Merry2 found more than 1500 people were killed or permanently disabled annually in this country through preventable medical error. They wrote:

“The evidence is incontrovertible—we are inadvertently harming an unacceptable number of our patients by the very healthcare intended to help them.”

An earlier New Zealand study found that “up to 30% of public hospital expenditure goes toward treating an adverse event”3, and that does not take into account the cost to individuals in both direct and indirect costs, loss of quality of life etc., and to the community in loss of productivity and participation. Brown et al found in 2002 that “adverse events are estimated to cost the medical system $NZ870 million, of which $NZ590 million went toward treating preventable adverse events.” [our emphasis]

While more recent statistics and costs for medical error in New Zealand are difficult to find, there is little reason to be confident that the situation has improved. In 2006 our stats were similar to the US2, so it is possible that medical error could be making a significant contribution to direct cause of death in this country.
The findings of a recent study by researchers at Victoria University of Wellington, Te Tātai Hauora o Hine Centre for Women’s Health Research and the University of Otago, has only contributed to an overall pessimistic picture of the quality of health care in our public health system.

In a paper titled “Preventability review of severe maternal morbidity”, Professor Beverley Lawton and colleagues found that “severe maternal morbidity† was 6.2 per 1000 deliveries with higher rates for Pacific, Indian and other Asian racial groups.”

“Major blood loss (39.4%), preeclampsia‐associated conditions (23.3%) and severe sepsis (14.1%) were the most common causes of SMM. Potential preventability was highest with sepsis cases (56%) followed by preeclampsia and major blood loss (34.3% and 30.9%). Of these cases, only 36.4% were managed appropriately as determined by multidisciplinary review. Provider factors such as inappropriate diagnosis, delay or failure to recognise high risk were the most common factors associated with potential preventability of SMM. Pacific Island women had over twice the rate of preventable morbidity.”

Lead author, Prof. Lawton, told the New Zealand Herald that “these women did not need to get as sick as they did and called the ethnic disparity in standard of care ‘unacceptable’”.5

The researchers concluded that their analysis showed “that over a third of cases were potentially preventable, being due to substandard provider care with increased preventability rates for racial/ethnic minority women.”
The study found that of SMM admissions to an ICU or HDU “overall, 34.1% were deemed potentially preventable and 29.5% not preventable but where improvement in care was needed, leaving 36.4% of reviewed cases deemed to be managed appropriately.”4

Of the three most common clinical reasons for admission, 56% of cases of severe sepsis, 34.3% of preeclampsia‐related conditions, and 30.9% of major blood loss were potentially preventable.4 Among potentially preventable cases, 93.4% were clinician related, with systems factors present in 60.6% and patient factors in 24.7%. Only in 5.3% of cases were patient factors the only preventable factor.

Underlining the ethnic disparities was the finding that among Pasifika women in whom potential preventability was significantly higher, clinician related factors were present in 100% of cases, systems factors in 67.2% of cases and patient factors in only 7.2% of cases.

Clinician factors were predominantly diagnostic – inappropriate, or delay or failure to recognise a “high risk patient – at 70.8%; and treatment – inappropriate, delay or failure to treat – at 88.8%.

In addition to the impact on the health of women, SMM adversely impacts outcomes for unborn or new-born babies, contributing to adverse delivery outcomes at a higher rate than among women without SMM.

“Adverse delivery outcomes such as fetal death, NICU admission, preterm birth, 5-min Apgar score less than 7 and low birth weight occur at a higher frequency among women with SMM.”6 An investigation into outcomes for babies in New Zealand found that “49.4% of women with SMM suffered one or more of these adverse delivery outcomes. Preterm birth is significantly associated with SMM, with between 22 and 41% of women with SMM having a preterm birth.”6

It simply is not good enough for New Zealand women to be receiving such grossly inadequate care, or for the quality of care to be so clearly tied to their ethnicity. So soon after the report that found a significant racial bias in resuscitation of premature babies in some DHBs (see the December 2018 AWHC Newsletter), this study is a sad indictment on the care provided to pregnant women in this country.

It has been shown that our neonatal mortality rates have not declined over the last ten years in the way that they have declined in many of the countries with which we compare ourselves.7 If this is to change, we must address the poor record we have with treating severe maternal morbidity and the contribution it makes to adverse outcomes for our babies.

* Medical error has been defined as an unintended act (either of omission or commission) or one that does not achieve its intended outcome, the failure of a planned action to be completed as intended (an error of execution), the use of a wrong plan to achieve an aim (an error of planning), or a deviation from the process of care that may or may not cause harm to the patient.1

† Severe maternal morbidity (SMM) or maternal near-miss are terms used to identify women with life-threatening complications in pregnancy. The World Health Organization defines near-miss morbidity (NMM) at the severe end of the morbidity spectrum as “the near death of a woman who has survived a complication occurring during pregnancy or childbirth or within 42 days of the termination of pregnancy”.4

  1. Makary MA and Daniel M: Medical error – the third leading cause of death in the US. British Medical Journal, 2016 May 3; 353: i2139.
  2. Merry A and Seddon M: Quality improvement in healthcare in New Zealand. Part 2: are our patients safe–and what are we doing about it? New Zealand Medical Journal, 2006 Jul 21; 119(1238): U2086.
  3. Brown P et al: Cost of medical injury in New Zealand: a retrospective cohort study. Journal of Health Services Research and Policy, 2002 Jul; 7 Suppl 1: S29-34.
  4. Lawton BA et al: Preventability review of severe maternal morbidity. Acta Obstetrica et Gynecologica Scandinavica, 2018 Dec 26.
  5. ‘Urgent action is needed’: A third of severe illnesses in pregnant women were potentially preventable, New Zealand Herald, 5 February 2019 accessed at
  6. Geller SE et al: A global view of severe maternal morbidity: moving beyond maternal mortality. Reproductive Health, 2018 Jun 22; 15(Suppl 1): 98.
  7. PMMRC: Twelfth Annual Report of the Perinatal and Maternal Mortality Review Committee, Reporting mortality and morbidity 2016; Eighth Report to the Health Quality & Safety Commission New Zealand, June 2018.