Background
Due to the development and subsequent commercialization of infant formula in the eighteenth, nineteenth and twentieth centuries, there has been a strong decline in breastfeeding rates worldwide [
1,
2]. However, an increasing body of research shows that breastfeeding has important positive long-term health consequences for infants and mothers. A 2016 meta-analysis of research into the health consequences of breastfeeding for mothers and children concluded that infants who are breastfed for longer periods have lower infectious morbidity and mortality, fewer dental malocclusions and higher intelligence than infants who are not breastfed or breastfed for shorter periods [
2]. Furthermore, breastfeeding may also protect against sudden infant death syndrome (SIDS), decrease the risk of necrotising enterocolitis (NEC) for premature babies, and protect children against overweight and diabetes later in life [
2]. The beneficial effects of breastfeeding for mothers include protection against breast cancer, improved birth spacing, and potential protection against diabetes and ovarian cancer [
2]. Moreover, it was estimated that scaling up breastfeeding to near universal levels could prevent approximately 823,000 child deaths and 20,000 deaths due to breast cancer worldwide annually. Breastfeeding therefore plays an important role in public health for mothers and children around the globe ([
2]; also see [
3‐
6]). As a consequence increasing the prevalence and duration of breastfeeding are important health goals in most nations. The World Health Organization (WHO) recommends that all infants should be exclusively breastfed (i.e., receive only breast milk and no other food or drink) for the first 6 months of life to achieve optimal growth, development, and health. Infants should receive complementary foods from 6 months, while breastfeeding should be continued for up to 2 years or beyond [
7]. However, these recommendations are not met in many countries. Recent research by the WHO found in a sample of 194 nations, that only 40% of children younger than 6 months are breastfed exclusively [
8]. Research findings also suggest that many mothers would like to breastfeed for longer, and that approximately 60% of US mothers stopped breastfeeding earlier than they desired [
9]. Mothers stopped breastfeeding prematurely mainly because they had concerns about maternal or child health and concerns about the breastfeeding process (e.g., lactation and milk-pumping problems). The researchers concluded that professional support could help to address these challenges and help mothers to attain their breastfeeding goals [
9]. Although some women cannot breastfeed for physical or medical reasons [
10], many women could benefit from breastfeeding support.
In the Netherlands, breastfeeding rates also leave ample room for improvement. Although Dutch breastfeeding rates have gradually increased in the past decades, and 80% of Dutch mothers initiate breastfeeding, only 39% of Dutch babies are exclusively breastfed at 6 months
1, according to a recent study [
11]. Moreover, many women in the Netherlands report difficulties with breastfeeding and do not maintain the practice for as long as they intended [
12]. In the past decades, national campaigns, emphasising the health benefits of breastfeeding, have been developed to extend the duration of breastfeeding [
13]. As part of these campaigns, virtually all hospitals and maternity organisations in the Netherlands have received Baby Friendly Hospital Initiative (BFHI) certification [
14], as developed by WHO in 1991 [
15]. With regard to breastfeeding recommendations, Dutch guidelines initially followed the WHO guidelines, advising to breastfeed exclusively for at least six months. However, in 2011 the Dutch breastfeeding recommendations were adjusted, in an attempt to prevent the development of food allergies in children [
16,
17]. Since 2011 it is therefore advised that mothers should breastfeed for at least six months [
18], but should start with complementary foods when the baby is between 4 and 6 months old, if possible [
19]. Therefore, exclusive breastfeeding until six months is no longer recommended in the Dutch breastfeeding guidelines; also no mention is made of continuation of breastfeeding for two years or beyond. These deviating national guidelines may partly explain why the prevalence of (exclusive) breastfeeding in the Netherlands is relatively low, and why breastfeeding support and education is especially important in the Netherlands.
Systematic reviews and meta-analyses on breastfeeding promotion interventions have shown that breastfeeding education and/or support can effectively increase breastfeeding rates [
20‐
26]. For instance, a recent meta-analysis, including 27 randomized controlled trials (RCT’s) and 36,051 mothers, found that breastfeeding support interventions aiming to increase exclusive breastfeeding for 6 months were indeed effective. A subgroup analysis looking into the effects of different types of interventions found that a BFHI intervention, an intervention combining education and support, a professional provider led intervention, an intervention that has a protocol available for the provider training program, and an intervention that takes place both during the prenatal and postnatal periods, all increased the rate of exclusive breastfeeding for 6 months [
26]. Likewise, a recent systematic review, focussing specifically on professional support interventions, found that interventions spanning from pregnancy to the postnatal period were more effective than interventions that took place in a shorter period, and that interventions using various methods of education and support were more effective than interventions concentrating on a single method [
22]. Moreover, it was found that during pregnancy, the BFHI as well as teaching combined with support were effective approaches. During the postnatal period effective approaches included home visits, telephone support, and the use of breastfeeding centres combined with peer support [
22].
The current study examines the effectiveness of a comprehensive, evidence-based, professional support intervention for breastfeeding that was implemented in the Netherlands: the Breastfeeding Support Program (BSP). The BSP was developed by two International Board Certified Lactation Consultants (IBCLC), based on theoretical findings and practical experiences. The Theory of Planned Behaviour (TPB) [
27] constitutes the theoretical framework for the BSP. The TPB states that human behaviour is predicted by three kinds of considerations: a person’s general evaluation of a given behaviour (attitude); a person’s beliefs about how relevant others will view the behaviour in question (subjective norm); and a person’s perceived ease or difficulty in performing the behaviour (perceived behavioural control). The attitude, subjective norm and perceived behavioural control combined lead to the formation of a behavioural intention to display a certain behaviour. As a general rule, the more favourable the attitude and subjective norm, and the higher the perceived control, the stronger the person’s intention to perform the behaviour in question. Finally, intention is assumed to be the immediate antecedent of behaviour. The TPB is a well-known framework for designing behavioural change interventions [
28], and several studies have shown that the TPB can be successfully applied to breastfeeding [
29‐
32].The BSP applies the TPB by aiming to influence positively a mother’s attitude towards breastfeeding, the subjective norm and her perceived behavioural control. The BSP is not only based on the TPB, but also integrates the empirical research findings from systematic reviews of support interventions for breastfeeding promotion [
22,
26], suggesting that the most effective interventions are usually delivered by well-trained professionals, combine education and support, and are long-term and intensive, spanning both the prenatal and postnatal period. Although evidence suggests that all these separate elements should increase the effectiveness of a breastfeeding intervention [
22,
26], studies that investigate their combined effect are still largely lacking.
The research question we will answer in this study is: do the mothers enrolled in the BSP engage in prolonged breastfeeding in terms of duration and exclusivity compared to mothers in a control group? Based on the accumulated research into the effectiveness of breastfeeding promotion interventions [
20‐
26], and on studies showing the successful application of the TPB to breastfeeding [
29‐
32], we hypothesized that the BSP is an effective intervention in principle. A test of this hypothesis further facilitates the elimination of unsound or ineffective practices in favour of those that have better outcomes, and as such this study aims to support the implementation of evidence-based practice.
Discussion
This study examined whether mothers enrolled in the BSP engage in longer and more exclusive breastfeeding compared to mothers in a control group. Controlling for differences at baseline, there was on average 66% less risk of cessation of any breastfeeding and on average 54% less risk of cessation of exclusive breastfeeding at any point of time among mothers in the BSP group compared to those in the control group. A subgroup analysis, including nulliparous women only, showed similar results, providing evidence for the robustness of the findings. In the current population, the BSP therefore appears to be an effective means to delay cessation of any and exclusive breastfeeding, and therefore to increase breastfeeding duration and exclusivity. This is an important finding, because breastfeeding rates are suboptimal in many countries [
8], and interventions which could increase breastfeeding rates are valuable given the positive effects of breastfeeding on the mothers’ and children’s health and well-being [
2‐
6]. Notably, our findings are in line with findings from systematic reviews and meta-analyses showing that breastfeeding promotion interventions can indeed effectively increase breastfeeding rates [
20‐
26].
A strong point of the BSP is that it is a very comprehensive breastfeeding intervention: it combines support and education, is led by a professional provider, has a protocol available, and is implemented during both the prenatal and postnatal periods. The programme is also evidence based, incorporating elements which have been proven to increase the effectiveness of a breastfeeding intervention [
22,
26]. Finally, the BSP has a firm theoretical foundation in the Theory of Planned Behaviour [
27].
The number of studies evaluating breastfeeding interventions in the Netherlands is very limited: only two other studies are known to us. One study evaluated a breastfeeding intervention aimed at extending the continuation of breastfeeding until at least 3 months by educating postpartum health professionals, but found no significant effect [
46]. Another study evaluated an educational programme to promote exclusive breastfeeding for 6 months in families with a history of asthma: breastfeeding exclusively at 6 months was significantly higher in the intervention group than in the control group [
47]. In comparison to this last study, the BSP offers the added benefit that it is not tailored to a specific group, but is in principle applicable to the general population. Therefore, the BSP might be deployed as an effective general support measure for mothers intending to breastfeed, to improve the relatively low breastfeeding rates in the Netherlands [
11].
An important limitation of the current research is that no randomization was performed, which led to pre-existing differences between groups. Although we believe we had valid reasons to opt for a quasi-experimental design (basing our decision on practical and ecological grounds), the lack of randomization could have resulted in pre-existing differences between the control and the intervention group that affected our findings [
33]. Pre-existing differences can pose a threat to internal validity, mainly if they are related to the outcome variable of interest, and can thus provide an alternative explanation for the effect of the intervention. Therefore, the quality of any quasi-experiment is dependent on the degree of comparability between treatment groups, and it is essential to screen and control for possibly confounding factors [
33]. In the current study we used post-hoc adjustment to control for potential confounders; another possibility is to prospectively match treatment groups on important confounding variables to create more comparable groups [
35]. However, matching can be difficult and sometimes impractical, for example when the sample size is limited compared to the number confounding factors [
48], as in the current study. Furthermore, controlling for differences has its limits, in the sense that one cannot control for unmeasured or imperfectly measured confounders [
35]. Although we carefully measured and controlled for a broad range of possibly confounding variables in this study, future studies testing the effectiveness of the BSP may consider using alternative designs, most notably those in which participants are randomly assigned to conditions. For example, a RCT where all participants receive some form of BSP, but in different forms or intensities, could prevent selection bias, while at the same time precluding unwanted bias from randomisation (such as low compliance or selective attrition [
36]). Studies focussing on the effectiveness of the current intervention at different intensities (e.g., more or fewer consults) and on the effectiveness of its various elements (i.e., which of the elements – information, practical advice or the role of the father etc. – contribute most to the programme’s effectiveness) could also help fine-tune the BSP, potentially making it more effective and efficient.
Another important limitation of the current research (related to the previous point) is that it is unclear to what extent the current findings are generalizable to other populations. The present research focussed explicitly on testing the effectiveness of the BSP among the current participants, and the sample of women in the BSP group was therefore self-selected. As a consequence, it is possible that certain characteristics of the current sample serve as moderators for the effectiveness of the intervention [
33]. Two characteristics of our sample seem noteworthy in this respect. First, the women in the BSP group can be characterized by a relatively high education level, and second, it seems that women in the BSP group may have anticipated breastfeeding problems or were planning to return to work. Although we controlled for these differences (making it unlikely that they compromised our results), future research may want to zoom in on their potential effects. For example, the BSP seems to be effective for the women that we investigated, but perhaps it is less effective for, for instance, lower educated women, women who do not anticipate breastfeeding problems, or women who do not plan to return to work. It seems likely that mothers encountering difficulties during breastfeeding could particularly benefit from participating in a BSP. Evidence to this effect could point towards the effectiveness of targeting pregnant women with a higher propensity towards breastfeeding problems. Because the present research showed promising effects in the current population, future research could consider sampling from a broader set of populations to test the differences of BSP effectiveness between sub-groups of women and to test the generalizability of the current findings. Finally, future studies could include more dependent variables, such as whether women sought additional breastfeeding support or the extent to which breastfeeding problems are perceived as effectively handled, to provide greater insight into the effects and working mechanisms of the programme.
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.