Study design and participants
The present randomized controlled clinical trial was a part of a comprehensive study in which the effect of prenatal counseling on the breastfeeding practice of mothers with previous unsuccessful breastfeeding was evaluated and the breastfeeding self-efficacy and frequency of breastfeeding problems were measured as secondary outcomes. The results of primary outcomes have been published in another article (24). This trial was conducted from November 2017 to May 2018 on 108 pregnant women who referred to the health centers in Tabriz, Iran. Inclusion criteria were the ability to read and write, residing in Tabriz, having previous unsuccessful breastfeeding, monogamy pregnancy, being able to constantly attend at counseling sessions, and being in the third trimester of their gestation. Exclusion criteria were fetal abnormalities, high-risk pregnancies, and breastfeeding contraindications.
The sample size was calculated based on the Kordi et al. study (25) and the “exclusive breastfeeding” variable. Forty nine participants were included in each group utilizing G-Power software and considering P1=40% (exclusive breastfeeding frequency in intervention group), P2=17.5% (exclusive breastfeeding frequency in control group), α= 0/05 and power = 80%. Finally, 54 participants were calculated to be the total sample size for each group, with a 10% of probable attrition rate.
Study outcomes
The outcomes of this study were breastfeeding self-efficacy and frequency of breastfeeding problems in mothers with previous unsuccessful breastfeeding.
Sampling and random allocation
The present study was approved by the committee of ethics of Tabriz University of Medical Sciences (IR.TBZMED.REC.1396.595) and was registered in Iranian Registry of Clinical Trials (IRCT20100109003027N19). Then, the samples were recruited utilizing available methods from all healthcare centers in Tabriz. After that, the researcher went to all healthcare centers and prepared a list of multipara pregnant women in their third trimester. The research aims were explained to eligible participants by phone calls and they were questioned on any previous unsuccessful breastfeeding experience. Then, they were evaluated in terms of inclusion and exclusion criteria in case of positive response to the former question and their readiness to contribute in the study. In case of eligibility, they would be invited to a briefing session. The study aims and method were explained and informed written consent was gained. Then, a socio-demographic questionnaire was completed. Participants were assigned into two groups, i.e. intervention recipient and control, using web www.random.org -based randomized block plan with block sizes of 4 and 6 and a 1:1 allocation ratio. Random allocation was done by an uninvolved person in sampling and data collection processes. Allocation concealment was done by writing the type of allocation on pieces of paper and placing them in consecutively numbered, opaque, sealed packets. Packets were opened in the order of participant entry in the study and they were allocated into either the counseling or control group.
Intervention
In the intervention group, a set of breastfeeding counseling sessions in clusters of 5-7 participants, with each session for a period 60-90 minutes was begun. Four counseling sessions were held within a one-week time period and the control group only received routine care provided by healthcare center. The educational context in intervention group included the profits and combinations of breast milk, the psychological benefits of breastfeeding, breast structure and physiology, breastfeeding hormones, common reasons of breastfeeding discontinuation and failure, common breast conditions and disorders, maternal nourishment during breastfeeding, and breast pumping tips. Also, an instructive booklet was provided to the intervention group at the end of preliminary session. Phone call or, if necessary, face to face counseling was scheduled by the same consultant until the day 15 and up to the end of the 4th month postpartum in case of any trouble. A researcher-made checklist of frequency of breastfeeding problems and the standard Breastfeeding Self-Efficacy Scale (BSES) were completed for both groups on day 15 and months 2 and 4 postpartum.
Data Collection Tool
In this study, self-efficacy was measured using self-efficacy measure (BSES) for breastfeeding. Breastfeeding self-efficacy includes 33 items and is scored on Likert Scale with the score 1 for “totally disagree” to score 5 for “totally agree”. The scores are 33 to165. Higher scores indicate higher levels of self-efficacy in breastfeeding. Bandura (1997) designed this tool , and Faux and Denis, for the first time, used it for breastfeeding (12). Shahri et al. (2015) conducted the psychometric evaluation of the Persian version of this scale (26). To determine the reliability BSES, test-retest analysis was carried out. The questionnaires were filled by 20 participants once, and the filling was repeated after 2 weeks, then the reliability was achieved by demonstrating in-line correlation coefficient and Cronbach alpha coefficient as 0.826 and 0.834, respectively, and then Confidence Interval (CI) was calculated to be 95%. In this study, the questionnaire was completed in three time intervals in the 15th day, 2nd and 4th month postpartum in both intervention and control groups. Breastfeeding problems were measured using a checklist of breastfeeding problems frequency designed by the present researchers. Breastfeeding problems such as inadequate milk, baby’s refusal to take the breast, breast common conditions and complications, and baby’s complications were compared at three time intervals of 2nd and 4th months and 15 days postpartum in both intervention and control groups.
Data analysis
SPSS software (version 24) was utilized for data analysis. The normal distribution of quantitative data was examined using the Kolmogorov–Smirnov test, indicating the normal distribution of all data. The socio-demographic features of both groups were compared using chi-square test, chi-square test for trend, independent t-test, and Fisher’s exact test. Analyses of the inter-group breastfeeding self-efficacy were conducted using chi-square test and repeated measure ANOVA test, the variables such as willingness to pregnancy, and mother/husband’s education were controlled. The inter-group frequency of breastfeeding problems were compared using chi-square and Fisher's exact test. p<0.05 was considered to be statistically significant.