The Cord Pilot Trial compared cord clamping after at least two minutes and providing immediate neonatal care, if needed, with cord intact (deferred clamping), with clamping within 20 s and neonatal care after clamping (immediate clamping) at very preterm birth (before 32 weeks gestation). The trial was conducted at eight UK tertiary maternity units. The protocol is published [6, 7]. Initially, the objective was to assess the feasibility of conducting a large multicentre UK trial. When feasibility was demonstrated, recruitment continued whilst funding for the full trial was sought. Recruitment closed when the funding application for the full trial was unsuccessful [11].
Two different consent pathways were used within the trial [6, 12]. Where possible the usual written consent process was used (one stage consent pathway). However if birth was imminent and there was insufficient time for the usual consent process, women could give oral assent to the trial prior to birth. After the birth, written consent for participation in follow up was sought from the women who provided oral assent (two stage consent pathway).
Women were asked to complete two similar questionnaires, the first between four and eight weeks after giving birth, the second at one year. We initially planned the first questionnaire would be posted to the woman’s home six weeks after the birth, but this often coincided with discharge of the baby which was not a good time for the women to receive it. Therefore, we changed this and if the baby was still in hospital at age four weeks, the research midwife/nurse gave the questionnaire to the woman when she was visiting. If the baby was discharged by age four weeks, we posted it to her when the baby was eight weeks old (or if the baby died, eight weeks after the birth). We posted a similar questionnaire to women at one year, along with a birthday card for the child (not sent if the child died). A stamped addressed envelope was provided to return completed questionnaires. If there was no response, we sent a postal reminder after two weeks. If there was still no response after another two weeks, we telephoned the woman and offered the opportunity to complete the questionnaire over the telephone. If no telephone number was available, we sent a second postal reminder. Before attempting to contact women, the study team checked contact details with the recruiting site. If contact could not be made, a letter was sent to the GP to check if the woman’s contact details had changed. If their baby had died and the woman did not respond, she was not contacted with reminders.
Questions used
The questionnaire included the Hospital Anxiety and Depression Scale (HADS) [13] to assess depression and anxiety; the Preterm Birth Experience and Satisfaction Scale (P-BESS) [14] to assess satisfaction with care at birth; and a section asking women about their baby’s feeding (not included if the baby had died). A final section asked about women’s experiences of participating in the trial, and the responses to these questions are reported separately [submitted for publication].
The HADS includes 14 questions, seven about anxiety and seven about depression in the past week, and has been used previously for parents of preterm babies [15]. Each question is scored from zero to three, and the seven items in each subscale are summed to create a score ranging from zero to 21 for either anxiety or depression. Higher scores indicate increased symptoms of anxiety or depression; a score of eight or more being suggestive of a mood disorder [16]. If a participant missed one item in the subscale, we used the mean of the completed items in that subscale to impute the missing item to calculate the subscale score. If more than one item was missing, the subscale score was not calculated. The P-BESS was developed specifically to assess parent’s satisfaction with care during very preterm birth and has 17 items each with a five point response scale (strongly disagree to strongly agree coded 1 to 5, some items reversed), in three subscales: interpersonal care (7 items, range 7 to 35), information and explanations (7 items, range 7 to 35), and confidence in staff (3 items, range 3 to 15). Missing items in each subscale were imputed using the mean of the completed items if 1 or 2 items were missing for the interpersonal care or information and explanations subscale or 1 item was missing for the confidence in staff subscale. The total score ranges between 17 and 85, with higher scores indicating greater satisfaction. We also asked whether the woman had ever breastfed or expressed milk for their baby and, if so, whether they were continuing to do so or the age of the baby when breastfeeding/expressing stopped.
Outcomes
For the initial feasibility trial, outcomes were the proportion of women responding and the reasons for losses to follow-up. Clinical outcomes were depression (HADS score ≥ 8); anxiety (HADS score ≥ 8); P-BESS total score and subscale scores; and for women who were breast feeding/expressing at discharge, duration of breast feeding/expressing.
Analysis
All analyses were based on the groups as randomly allocated (intention to treat). Women who gave birth after 35+ 6 weeks gestation were excluded from the analysis of outcomes to discharge, as outcome for these babies are different from those born very preterm [8]. They are therefore also excluded here. Response rates for the two questionnaires were described, along with reasons for losses to follow-up. Baseline and characteristics at birth for women who did not respond were explored. Scores on the HADS and P-BESS questionnaires were summarised descriptively. Duration of breast feeding/expressing from birth was described using Kaplan Meier curves for women who had ever breastfed/expressed and their baby survived to one year, censoring at the last known time of breastfeeding/expressing.