Funding for this research was provided by:
Medical Research Council (MR/L009226/1)
National Institute for Health Research (P45272)
Genesis Research Trust (P51389)
Received: 18 July 2017
Accepted: 20 December 2017
First Online: 24 January 2018
Ethics approval and consent to participate
: Ethics approval for this studied was granted by the National Research Ethics Service Committee London–Stanmore of the National Health Service (REC 14/LO/0328), and all participants provided written informed consent.
: PRB serves as a consultant for ObsEva, a company that works in the field of preterm birth. All other authors declare that they have no competing interests.
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