NZ COMCORD data adds yet more evidence of home birth safety

Data from the New Zealand College of Midwives Clinical Outcomes Research database (NZCOMCORD) add further weight to the evidence showing home and primary unit settings to be a safe option for birthing women and their babies (Dixon et al 2014).

Researchers analysed retrospective data from 61,072 women who were considered ‘low risk’. Eight per cent of them planned a home birth and 16.6% planned to give birth in a primary unit. As was also found in the Birthplace study, those women who planned to give birth at home were more likely to be older and multiparous. The NZ data also showed some significant contrasts, however, most notably in relation to transfer rates which were considerably lower than in the UK Birthplace research. It should be noted that some of the apparent disparity may be partly because there were some differences between the two datasets and the women who were included in the studies – not least of which is that the Birthplace study was prospective whereas the NZCOMCORD provides retrospective data – but this are unlikely to explain differences as significant as the comparative transfer rates. As someone who has been involved in midwifery in both countries, I am not at all surprised at the existence and magnitude of this contrast in transfer rates, which in my opinion is likely to be due to differences in the cultures and systems of care.

The findings on perinatal mortality and morbidity are interesting:

“The actual number of perinatal mortality outcomes was low across all settings in New Zealand and differences were not statistically significant (p< 0.14). We were unable to discern whether the perinatal death occurred before or after the commencement of labour in the dataset or whether mortality was due to lethal congenital anomaly. A significantly higher proportion of babies had Apgar scores of less than seven, and/or were transferred to a neonatal unit when the planned place of birth was a secondary or tertiary hospital (p=0.0001).” (Dixon et al 2014: 15)

It is just great to see so much data coming out from different countries supporting the safety and value of a variety of different birthing environments and options for women and their families. Kudos to the New Zealand midwives whose care has translated into these great outcomes. The study abstract is below, and the original is freely available online.

See all my posts relating to the safety of home birth:

Is home birth safe?

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The Research

Background: Choice, safety and availability of different birth settings are important issues for women and midwives in New Zealand (NZ). In England, the Birthplace England Research Study (BPE) has provided detailed information on outcomes for low risk women related to place of birth. These outcomes cannot be generalised to New Zealand owing to differences in context, culture and models of maternity care.

Aim: This observational study has used retrospective data to determine demographic differences between planned birth place setting, neonatal outcomes and transfer rates for a cohort of low risk New Zealand women and compared these findings where possible with those of the Birthplace England research.

Method: Data from the New Zealand College of Midwives Clinical Outcomes Research (NZCOMCORD) database were analysed for the years 2006 to 2010 inclusive for low risk women. Comparisons have been made between place of birth (home, primary unit) and parity, ethnicity, age, body mass index, transfer rates, and neonatal outcomes (Apgars, NICU admission, perinatal mortality).

Results: There were 61,072 women considered low risk, of whom 8% had planned a home birth and 16.6% a primary unit birth. Women who planned to birth at home in New Zealand were older and more likely to be multiparous. These were similar findings to those of the Birthplace England study. The rates of transfer from home (16.9%) or primary unit (12.6%) to hospital were lower than the Birthplace England cohort (21%). There was a higher proportion of nulliparous women (35%) in the planned homebirth group who transferred although this was significantly lower than the Birthplace England cohort (45%) (P<0.002). NZ Māori are the indigenous ethnicity of New Zealand, and a greater proportion of Māori planned birth in a primary unit (27.2%) than a secondary unit (23.2%), home (17.4%) or tertiary hospital (11.1%). The actual number of perinatal mortality outcomes was low across all settings for low risk women in New Zealand and differences in birthplace were not statistically significant (p < 0.14).

Conclusion: A greater proportion of indigenous New Zealand women planned to birth at home or in a primary unit. Fewer women were transferred in labour in the NZ study. This research further refines our understanding of who plans to birth where, and reinforces the evidence that, where a low risk woman plans to birth in NZ, does not significantly increase adverse outcomes for her baby.

Dixon, L., Prileszky, G., Guilliland, K., Miller, M., Anderson, J. (2104). Place of birth and outcomes for a cohort of low risk women in New Zealand: A comparison with Birthplace England. NZCOM Journal 50, 11-18 http://dx.doi.org/10.12784/nzcomjnl50.2014.2.11-18