A new method taking care of premature infants at birth is going to be introduced in several
hospitals in Sweden. The new method includes delayed cord clamping (> 3 minutes) and early
skin-to-skin contact with a parent. If the infant needs help with the breathing this can be
given during the time when the cord is still intact. This method is different from the
traditionally way used for the moment when the the cord is clamped soon after the infant is
born and bring the infant to a resuscitation table, often outside the delivery room, to
stabilize the infant, for example with support for the breathing with ventilation, CPAP
(Continuous Positive Airway Pressure) or intubation.
The PreDECESS trial will study how this delayed cord clamping and skin-to-skin contact will
affect the infants and their parents.
The study will have a cohort of premature infants taken care of at birth in the traditional
way and another cohort of infants taken care of with the new method. The study will be
prospective and the control group will be enrolled first and the active group after the new
method has been introduced. It will be multi-center study and hospitals in Linköping,
Norrköping, Kalmar, Lund and Huddinge will participate. Infants born in gestational weeks
30+0-34+6 through vaginal delivery and admitted to neonatal ward in Sweden will be included.
The trial is going to study bonding with Swedish Mother-to-Infant Bonding Scale (S-MIBS) and
Postpartum Bonding Questionnaire (PBQ). Both parents will also fill in questionnaires for
evaluation of depression which might have an impact on bonding, Edinburgh Postpartum
Depression Scale (EPDS). There might be connections between bonding and breast-feeding and
for that analysis we will use Breastfeeding Self efficacy scale (BSES-SF), a questionary
which mothers will answer. The infant's neurological development will be evaluated with a
questionary to parents, Ages and Stages Questionnaires (ASQ-3). Infants and parents stress
will be measured with cortisol and oxytocin in saliva. The infant's temperature, heart
frequency, oxygen saturation, oxygen level and need of respiratory assistance for the first
three hours after they are born will be documented. Blood sugar, haemoglobin and bilirubin
will be taken as part of the clinical practice. ProBNP will be taken when other laboratory
parameters are taken as an indicator of heart function. Residual blood in the placenta after
cord clamping will be measured. Data from the neonatal period will be collected from the
Swedish Quality Register (www.snq.se), and maternal data will be collected from the Swedish
Pregnancy Register (www.graviditetsregistret.se).
A validation of the Swedish Mother-to-Infant Bonding Scale (S-MIBS) will be a part of the
trial since this has not been done on premature infants.
A qualitative study where we will interview parents to explore their experiences with
premature birth, will also be part of the trial. Parents from both epochs, before and after
introduction of the new method, will be asked to be included in the sub study. This
qualitative part will be done in the hospitals in Linköping and Norrköping.
Cortisol and oxytocin in saliva before and after the introduction of the new method will be
analysed as stress markers.
At least 63 infants in the controlgroup has to be included. This makes it possible to analyse
two of our most important questions. The first is hypothermia that is a risk factor with the
new method. Thermal control has previously been documented as a cornerstone in a study with
immediate skin-to skin contact with parents for premature infants born in gestational weeks
28+0 to 31+6. The second important question is the validation of the Swedish Mother-to-Infant
Bonding Scale(S-MIBS). After 63 mothers in the controlgroup have answered S-MIBS we will do
an interim analysis to decide the final number participants needed in the trial. If the
differences are small between the control group in our study and the suspected outcome in the
active group (assumed from normal material previously described in a study where S-MIBS were
validated on mothers to healthy fullborn infants by our research group), there will be needed
very many infants to prove differences between the two groups. Therefore the study has an
upper limit set on 6 months as time for inclusion of the control group at every study site.
However, the inclusion will continue until at least 126 infants have been included, ie the
inclusion time could be longer than 6 months in that situation.
Intention to treat analyses will be applied. Per protocol analyses will also be done
including only infants and mothers in each study group that have followed the study protocol.
In the control group mothers should not have skin-to-skin contact with the infants for more
than 5 minutes during the first 10 minutes and more than 30 minutes for the first 2 hours to
participate in the per protocol analysis. The same applies to the infants, but for some
safety analyses there must also not have been delayed cord clamping (> 3 minutes). In the
interventiongroup mothers and/or partners should have skin-to-skin contact with the infant
all the time except when procedures like resuscitation or insertion of an intravenous line
has to be done. The infant should have delayed cord clamping according to the criteria.
Sensitivity tests of intention to treat analyses can be done with help from the per protocol
analyses.
Descriptive statistics will be used for all quantitative outcome measures: mean ± standard
deviation and median ± interquartile range. For qualitative outcome measures proportions
and/either percent will be used.
For both primary and secondary outcomes Chi2 test (or Fisher´s exact test if any suspected
value is less than 5 )will be used to calculate dichotomous values, t-test to calculate
continous data which are normally distributed and Mann-Whitney U test for not normally
distributed data. For correlation analysis Pearson and Spearman will be used. Regression
models (multiple linear, Cox proportional hazards depending on sort of data) will be used to
adjust for potential confounders like gestational week, birth wight, gender, APGAR-score and
study site. Relative effect of the intervention will be describes with 95% confidence
intervals. All analysis will be given account with two-sides 5 % level of significance.
Approval by the Swedish Ethical Review Authority have been obtained for the trial (Dnr
2022-01611-01).