Fetal and Infant Deaths 2012

These tables present a summary of fetal and infant deaths, with a focus on deaths and stillbirths registered in 2012 with the Births, Deaths and Marriages Registry (BDM). Information presented includes demographic information (eg, ethnicity and sex), cause of death, gestation and birthweight, as well as deaths classified as sudden infant death syndrome (SIDS) and sudden unexpected death in infancy (SUDI).

This dataset is a continuation of the Fetal and Infant Death series. In previous editions of this series, individuals who were not identified as Māori or Pacific were presented as being part of the 'Other' ethnic group (eg, NZ European, Chinese, Indian, Middle Eastern, Unknown). In this edition, individuals of Asian ethnicity (but not Maori or Pacific) are grouped as 'Asian' and all other individuals are grouped as 'European or Other'.

Key findings for 2012

Overview

• There were 448 fetal deaths and 294 infant deaths registered with Births, Deaths and Marriages in 2012.
• This equates to a fetal death rate of 7.2 per 1000 total births and an infant death rate of 4.7 per 1000 live births.
• Between 1996 and 2012, there was a statistically significant decrease in the infant death rate. The rate fell by 35%, from 7.3 to 4.7 per 1000 live births.
• The fetal death rate fluctuated between 5.9 and 8.6 per 1000 total births over the same time period.

Ethnic group

• Fetal death rates were highest for the Asian ethnic group in 2012 (8.7 per 1000 total births). Māori, Pacific and European or Other ethnic groups had similar fetal death rates that were lower (7.0, 7.1 and 6.8 per 1000 total births, respectively).
• The largest changes in the 2012 fetal death rate compared to the previous five-year period (2007–2011) was for the Pacific ethnic group with a 21% decrease and for the Asian ethnic group with a 14% increase.
• Infant death rates for Māori (5.7 per 1000 live births) and Pacific peoples (6.9 per 1000 live births) were 1.4 and 1.7 times, respectively, the rate for the European or Other ethnic group (4.1 per 1000 live births).
• There was a 19% decrease in the infant death rate for Māori in 2012 compared with the previous five-year period (2007–2011). Rates for the other ethnic groups did not show change.

Maternal age group

• The fetal death rate in 2012 was highest for babies of older women (12.2 per 1000 total births for the 40+ years age group), followed by babies of young women (10.5 per 1000 total births for the <20 years age group).
• The trend in 2012 was similar to previous years with higher fetal death rates seen in babies of young and older women and lower rates seen in babies of women aged 20–39 years.
• Babies of young women (<20 years age group) also had the highest infant death rate, at 8.5 per 1000 live births. The rate was lowest for babies of women in the 30–34 years age group.
• Infant death rates in 2012 were similar to rates in the 2007–2011 period for all maternal age groups.

Socioeconomic deprivation

• In 2012, the fetal death rate was highest among those residing in the most deprived areas. The rate for quintile 5 (9.3 per 1000 total births) was about 1.5 times the rate for all other quintiles (average of 6.4 per 1000 total births).
• As with the previous five-year period (2007–2011), infant death rates in 2012 were higher among babies residing in more deprived areas than for those residing in less deprived areas. The infant death rate for quintile 5 (most deprived) was 8.1 per 1000 live births. This was almost three times the rate for quintile 1 (least deprived) at 2.8 per 1000 live births.

Gestation

• Approximately 81% of fetal deaths were preterm (<37 weeks’ gestation), the majority of which were very preterm (<32 weeks’ gestation).
• Of the infant deaths registered in 2012, 61.7% were born preterm, the majority of which were born very preterm.

Birthweight

• Approximately 64% of fetal deaths and 44% of infant deaths registered in 2012 had an extremely low birthweight (<1000g).

District health board region

• There was a wide range of fetal and infant death rates across district health boards (DHBs).
• Whanganui DHB had the highest fetal and infant death rates (15.2 per 1000 total births and 10.7 per 1000 live births, respectively); both were statistically significantly higher than the respective national rates.
• Fetal death rates were lowest in West Coast and Taranaki DHBs (2.4 and 3.8 per 1000 total births). The lowest infant death rate was in Wairarapa DHB with no infant deaths registered in 2012. The infant death rate for Waitemata DHB was statistically significantly lower than the national rate.

Cause of death

• Almost 70% of fetal deaths had a cause of death in the ICD-10 chapter group ‘Certain conditions originating in the perinatal period (P00–P96)'; the most common specified cause of fetal death being ‘Slow fetal growth and fetal malnutrition (P05)’, followed by ‘Disorders related to short gestation and low birth weight, not elsewhere classified (P07)’.
• ‘Fetal death of unspecified cause (P95)’ accounted for 42% of all fetal deaths.
• ICD-10 chapter groups ‘Certain conditions originating in the perinatal period (P00–P96)’ and ‘Congenital malformations, deformations and chromosomal abnormalities (Q00–Q99) accounted for 50% and 24%, respectively, of infant deaths.
• The most common cause of infant death was ‘Disorders related to short gestation and low birthweight (P07)’ (21%).

Sudden unexpected death in infancy (SUDI)

• There were 36 deaths recorded as sudden unexpected death in infancy (SUDI) in 2012, including 18 sudden infant death syndrome (SIDS) deaths. These SUDI deaths included 22 males and 14 females.
• The SUDI rate in 2012 was 0.6 per 1000 live births, a 40% decrease from the previous five-year period (2007–2011) of 1.0 per 1000 live births.
• Between 2008 and 2012, the SUDI rates were generally higher among babies born with a very low birthweight (1000g–1499g) (3.3 per 1000 live births), to young mothers under 20 years (2.7 per 1000 live births), and at 32–36 weeks’ gestation (2.3 per 1000 live births). The SUDI rate for Northland, Lakes, Whanganui and Hutt Valley DHBs were statistically significantly higher than the national SUDI rate.

Note: The number of fetal and infant deaths in New Zealand is small and may cause rates to fluctuate markedly from year to year. Rates derived from small numbers should be interpreted with caution. The denominator for percentage calculations is the total for each variable for which the information was recorded and excludes 'Unknown' categories.