‘Both parents should care for babies’: A cross-sectional, cross-cultural comparison of adolescents’ breastfeeding intentions, and the influence of shared-parenting beliefs

There are notable national differences in breastfeeding initiation and maintenance. In Scotland, 74% of new mothers initiate breastfeeding [12], comparing unfavourably with England (83%). Northern European countries, including Norway, Finland and Sweden, have initiation rates around 98% [13‐15]. Rates for the USA were 77% in 2013, with significant differences between states [16]. Understanding and measuring cultural difference and its impact on health behaviours is complex, with as many cultural variations within countries as between them [17]. Cultural influences operate at different levels, including individual psychosocial factors, inter-generational transmission within families, social and community influences [18], socio-economic status (SES) and ethnic differences [17]. National policies supporting parents, including maternity and paternity leave and hospital and community healthcare are important [19, 20]. This study aims to learn from studying the impact of cultural norms on individual psychosocial influences on adolescents’ infant feeding and parenting beliefs, examining shared sets of beliefs, meanings and values (social norms) which are socially transmitted guide behaviour, and shaped by lived experiences [21], comparing countries with high (Sweden, Finland, Norway) and low (Scotland, USA) breastfeeding initiation rates.

Infant feeding decisions are often made early, before pregnancy [22]. Discussing these choices with young men and women (pre-parenting) is important, and school-based interventions promoting breastfeeding are valuable [19, 23, 24] (but with little evidence of long-term influences on behaviour). Breastfeeding is often discussed in the context of sex education, child development, or nutrition [25] which young people (and teachers) may find embarrassing, or seemingly irrelevant. For more lasting cultural change, a different approach is needed. Breastfeeding choices may appear more relevant to young men and women when discussed in the broader context of their desired parenting roles and intentions [23]. However, it is unclear how shared parenting beliefs relate to adolescents’ breastfeeding intentions. Since only the mother can breastfeed, partners may feel excluded from early parenting and ‘bonding’ with the infant [26], affecting both parents’ decision making [27]. Partners’ support for the breastfeeding mother is important for maintaining breastfeeding for recommended periods [28, 29]. A decision to formula-feed may reflect preference for more childcare involvement from the father [30] or lack of breastfeeding support.

The theory of planned behaviour (TPB) [31] is useful for assessing the influence of socio-cognitive factors [32], and has been applied to infant feeding in new parents, [33, 34], parents-to-be [35], and non-pregnant adolescents [24, 36]. Demographic factors, including ethnicity, age, sex and SES are important confounders [37] when included as first-line predictors [38].

We compared (non-parent) male and female adolescents’ shared parenting beliefs, norms, confidence and intentions and breastfeeding and formula feeding intentions, in countries with contrasting breastfeeding rates. Research questions were:

In central Scotland, three schools in urban areas with a broad socio-economic mix were invited to participate with prior permission from the Local Education Authority. In Sweden, two schools in the Mälardalen region (mixed SES metropolitan area around Stockholm) were contacted and agreed to participate. Parents’ permission was sought on an ‘opt-out’ basis for pupils. A hard copy letter invited parents to respond by returning a slip to school to exclude their child; no opt-out requests were received in either country. With consent, paper-based surveys were completed and placed in sealed envelopes by participants, collected and returned to researchers unopened by teachers (Scotland, Sweden).

Identical on-line surveys [39], were distributed by teachers in schools in Norway and the USA. In Norway, 3 schools around Oslo, (mixed SES) were recruited by personal contact. Parents first received hard-copy opt-out letters as above. Pupils later completed on-line surveys in school settings, having consented to take part. In the USA, permission was requested from school district administrators in Texas. A survey link was then forwarded to parents to first seek consent and then pass on to the participant.

In Finland, a ‘snowballing’ method and a popular internet site for young people (http://​irc-galleria.​net) recruited school aged participants in the urban Helsinki area.

For Sweden, Norway and Finland, the questionnaire was translated and back-translated into the first language using a translation service, and checked for face validity. In the USA, some terminology was changed (e.g. ‘nappies’ (UK) to ‘diapers’ (USA)).

Most (96%) of US participant responses came from 14 urban counties in Texas, (77% breastfeeding initiation, approximating the US national average [16]). Others (4%) came from Ohio, Michigan, and Arkansas.

Participants were school pupils aged 12–18. Sample size was estimated using a priori power analysis with G*Power [40]. Using linear regression with 13 predictors, medium ES, α = .01, 90% power, we required 192 participants. We recruited additional participants to allow for missing data, and to enable sub-group analysis.

The study was given ethical approval by the host institution’s University Psychology Ethics of Research Committee, including approval to collect data in Sweden, Finland and Norway subject to local permissions and with local school approval from Scottish education authorities. Authorities deemed this sufficient to negate the need for further institutional ethical review in Sweden and Norway, where additional school-based permissions were then obtained, and in Finland, where additional permission was given by a national social networking site adminstrator. The Internal Review Board of Texas A&M University (Central) gave USA approval.

All participants obtained parental consent to participate, using slightly different methods (see above). Immediately before completion the voluntary nature of the questionnaire was emphasised to potential participants who were given the opportunity not to participate. The on-line version included mandatory check boxes indicating prior parental consent and participant consent, before the questionnaire would open. It was incentivised for individual participants (young people) offering an on-line voucher for every 25th response. Inclusion in this draw, (via their email) was voluntary.

Age was coded into 3 categories: 12–13, 14–15, 16–18. Mothers’ highest level of education provided a proxy for SES [12, 41]. In Scotland we recorded four levels; ‘standard grades’ (national qualification, age 15–16), ‘highers’ (national qualification, age 16–18), vocational qualifications and university degree. Equivalents were determined for USA and Nordic countries.

The main study outcomes was infant feeding intentions. Predictors were infant feeding beliefs, measured in a TPB framework, measuring beliefs/attitudes, norms, perceived behavioural control and parenting beliefs, including attitudes, gender norms and confidence. Scales’ reliability was established using Cronbach’s alpha throughout (α).

For consistency, we defined infant feeding at the start of questionnaires: Breast-feeding – baby gets milk from the mother’s breast; Formula-feeding – baby gets formula/powdered milk from a bottle. Combined feeding – baby gets both breast milk from the mother and formula milk from a bottle.

Participants were asked how they had been fed themselves as a newborn; (options: ‘breast-fed’, ‘formula-fed’, ‘combined-fed’, ‘don’t know’). We combined the ‘breast-fed’ and ‘combined-fed’ responses, and excluded ‘don’t know’ to create a dichotomous variable representing ‘any breast-feeding’ vs. ‘no breast-feeding’.

We asked how they wished to feed their baby if they became a parent, with fixed choice options as above, creating a dichotomous ‘any breast-feeding’ variable for analysis.

Items previously used with new parents and adolescents in Scotland [34, 36] measured behavioural beliefs about breastfeeding and formula feeding, avoiding social desirability bias towards breastfeeding as a desired health behaviour. Initially, thirteen items were scored on a Likert scale: 1 ‘strongly disagree’ to 7 ‘strongly agree’. PCA with varimax rotation identified a forced 2 factor solution with four variables eliminated (using cut-off 0.4, [42]) since they did not load onto either factor. Factors represented positive (4 items, 19.6% of variance) and negative beliefs about breastfeeding (5 items, 27.8% of variance). Positive beliefs included: ‘breastfeeding leads to a close bond between mother and baby’, ‘…helps get the mother’s figure back to normal’, ‘…is a natural way of feeding babies’, and ‘formula feeding is expensive’ (α = .59). Negative beliefs included: ‘formula feeding makes it easier for mother to go back to work’, ‘breastfeeding is embarrassing for the mother’, ‘breastfeeding spoils the shape of the mother’s breasts’, ‘breastfeeding limits the mother’s social life’, and ‘breastfeeding can be uncomfortable for the mother’ (α = .67). Reliability of factor solutions remained consistent in each cultural group.

We assessed descriptive (what other people do) and injunctive (subjective) norms (perceived social pressure) [43].

‘Exposure’ to breastfeeding and formula feeding was calculated, from 4 social referent groups at variable social distance [36] (family member, friend, someone you don’t know, someone on television), e.g.: ‘how often have you seen a close family member breastfeeding a baby?’, scored 1–4; ‘never’, ‘1–2 times’, ‘3–10 times’, ‘more than 10 times’, summed to represent total exposure to breastfeeding and formula feeding (range 4–16).

Subjective norms (SN) were measured with 2 single items using a 7 point Likert scale with anchors as above: ‘People important to me would want me to breastfeed/formula feed my baby’.

Two summed items measured perceived control for each parent: ‘For the mother, breastfeeding a new baby would be..’; ‘For the father, helping to feed a new baby would be..’ scored on a 7 point Likert scale from ‘very difficult’ to ‘very easy’, (α = .52).

Taking the whole sample, most participants (662, 63%) ‘definitely’ intended to be a parent, a third (346, 32.4%) were unsure, and few (51, 4.8%) definitely did not want to become a parent. More females (66%) than males (58%) definitely wanted to become a parent, whereas more males (38%) were unsure than females (29%). More females (5.3%) than males (4.0%) ‘definitely’ didn’t want to become a parent (χ² (2) = 8.9, p = .012). There were striking differences by country. Only 41% of participants in Scotland ‘definitely’ intended to become a parent, compared with 71% in the USA and 71% in Nordic countries (χ² (4) = 41.8, p < .001).

We investigated differences in TPB psychosocial factors (beliefs, norms and confidence) related to both breastfeeding or formula feeding and parenting, comparing adolescents in countries with high and low breastfeeding rates. Table 3 shows mean comparisons for TPB infant feeding variables by national group, age group and sex, using 3x3x2 factorial ANOVA, and correlations for the whole sample. There were highly significant national effects for all infant feeding variables. Scottish participants had lower positive and higher negative breastfeeding beliefs, less breastfeeding exposure, less positive breastfeeding norms, more positive formula feeding norms and lower breastfeeding confidence. USA participants had most positive and least negative breastfeeding beliefs and most formula feeding exposure. Effect sizes (partial η²) were generally small.

There were no age differences apart from breastfeeding exposure, where older groups had significantly more exposure. Sex effects were significant for breastfeeding and formula feeding exposure and breastfeeding norms. Females had higher mean scores for all variables apart from formula feeding norms. Table 3 shows positive breastfeeding beliefs were positively correlated with other feeding variables. Norms and exposure were positively related and more positive beliefs and norms indicated more infant feeding confidence.

There were some methodological issues which may have affected the reliability of results. Using an ‘opt-out’ methodology for recruitment may have been ethically questionable – we could not be certain that parents had received the information, and participants may have felt pressurised to participate in school settings. Nevertheless we would justify our approach here in terms of ensuring adequate sample size and representativeness [48]. The sample sizes and demographic characteristics were unbalanced. The Scottish sample was larger and younger, and there were fewer males in Nordic and USA samples, although we did not find evidence that this biased results. We know that SES is a key variable affecting breastfeeding rates. We measured mother’s education level as a proxy variable for SES, as we anticipated it would be difficult to code cross-national data on occupation reliably. Nevertheless, several participants did not (or could not) provide this information, so missing data was an issue for this variable. Since it was difficult to establish equivalence across samples we did not include this in the final regression model. The omission of ethnicity measurement was less important for our Scottish sample, which has a largely White British composition, than for the other countries. However Texas has larger proportions of Black American and Hispanic groups, and future work should include reliable measurement of ethnicity. We used variable sampling methods, and cannot estimate bias in terms of response rates. Data in schools was collected on a class by class basis, so may have reflected social desirability and teacher’s interest. The social networking approach used in Finland may have incurred socio-economic biases in respondents using particular websites. Since there were several univariate statistical tests carried out with the data, there was also potential for Type 1 errors.