Fetal and Infant Deaths 2013

Summary

These tables present a summary of fetal and infant deaths, with a focus on deaths and stillbirths registered in 2013 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 editions of this series prior to 2012, 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). Since 2012, individuals of Asian ethnicity (but not Māori or Pacific) are grouped as 'Asian' and all other individuals are grouped as 'European or Other'.

Key findings for 2013

Overview

• There were 392 fetal deaths and 296 infant deaths registered with Births, Deaths and Marriages in 2013.
• This equates to a fetal death rate of 6.5 per 1000 total births and an infant death rate of 5.0 per 1000 live births.
• Between 1996 and 2013, there was a statistically significant decrease in the infant death rate. The rate fell by 32%, from 7.3 to 5.0 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 Pacific ethnic group in 2013 (7.6 per 1000 total births). Māori, Asian and European or Other ethnic groups had similar fetal death rates that were lower (6.8, 6.8 and 6.0 per 1000 total births, respectively).
• In 2013 the fetal death rate was 13–15% lower than the rate in the previous five-year period (2008–2012) for all ethnic groups.
• In 2013 infant death rates for Māori (5.3 per 1000 live births) and Pacific (7.6 per 1000 live births) ethnic groups were 1.2 and 1.7 times respectively, the rate for the European or Other ethnic group (4.4 per 1000 live births).
• There was an increase in the infant death rate for Asian (36.2%) and Pacific (14.2%) ethnic groups in 2013 compared with the previous five-year period (2008–2012). Infant death rates for Māori in 2013 decreased by 23.8% compared to this five year period. There was little change for the European or Other ethnic group.

Maternal age group

• The fetal death rate in 2013 was highest for babies of older women giving birth (12.8 per 1000 total births for the 40+ years age group), followed by babies of young women (9.9 per 1000 total births for the <20 years age group).
• The trend in 2013 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) had the highest infant death rate, at 11.1 per 1000 live births. The rate was lowest for babies of women in the 30–34 years age group.
• Infant death rates in 2013 increased by 60% for babies of women aged 40+ years, compared to rates for the five years previous (2008–2012). Rates in 2013 were similar to rates for the previous five years for all other maternal age groups.

Socioeconomic deprivation

• In 2013, the fetal death rates for those residing in the more deprived areas (quintiles 3–5) were higher than the rates for those in the less deprived areas (quintiles 1–2).
• As with the previous five-year period (2008–2012), infant death rates in 2013 increased with each level of deprivation. The infant death rate for the most deprived areas (quintile 5, 7.4 per 1000 live births), was 2.5 times the rate of the least deprived areas (quintile 1, 3.0 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 2013, 65.9% were born preterm, the majority of which were born very preterm.

Birthweight

• Approximately 60% of fetal deaths and 46% of infant deaths registered in 2013 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).
• Wairarapa DHB had the highest fetal death rate (19.7 per 1000 total births and significantly higher than the national rate), followed by West Coast DHB (10.1 per 1000 total births). Fetal death rates were lowest in Hutt Valley and Bay of Plenty DHBs (3.7 and 3.9 per 1000 total births respectively).
• South Canterbury DHB and Counties Manukau DHBs had the highest rates of infant deaths (9.5 and 8.0 per 1000 live births respectively).The rate for Counties Manukau DHB was statistically significantly higher than the national rate.
• The lowest infant death rate was in Waitemata and West Coast DHBs (both 2.6 per 1000 live births). The rate for Waitemata DHB was statistically significantly lower than the national rate.

Cause of death

• Approximately 75% 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 46% 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 51% and 24%, respectively, of infant deaths.
• The most common cause of infant death was ‘Disorders related to short gestation and low birthweight (P07)’ (19.9%).

Sudden unexpected death in infancy (SUDI)

• There were 41 deaths recorded as sudden unexpected death in infancy (SUDI) in 2013, including 20 sudden infant death syndrome (SIDS) deaths. These SUDI deaths included 25 males and 16 females.
• The SUDI rate in 2013 was 0.7 per 1000 live births, less than half the rate in 2000, 1.5 per 1000 live births.
• In the five-year period, 2009–2013, the SUDI rate for babies of the Māori ethnicity was statistically significantly higher than all other ethnic groups. Likewise, the SUDI rate for babies born in the most deprived areas (quintile 5) was statistically significantly higher than the rate for all other deprivation quintiles.
• During this same period, 2009–2013, SUDI rates were generally higher among babies born with a very low birthweight (1000g–1499g) (3.4 per 1000 live births), to young mothers under 20 years (2.4 per 1000 live births), and at 32–36 weeks’ gestation (2.2 per 1000 live births). The highest SUDI rate was in Northland and Whanganui DHBs (1.8 per 1000 live births; the rate for Northland DHB was statistically significantly higher than the national SUDI rate). Both Waitemata and Auckland DHBs had statistically significantly lower rates than the national 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.