Received: 10 October 2018
Accepted: 19 February 2019
First Online: 28 February 2019
Ethics approval and consent to participate
: Ethical approval for this study was granted by the Robert Gordon University School of Nursing and Midwifery ethics committee. Permission to access the anonymized (de-identified) data was granted by the Aberdeen Maternal and Neonatal Database steering committee.
: All data was anonymised so individual consent for publication was not applicable.
: The authors declare that they have no competing interests.
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