The Correlation Between Breastfeeding and Maternal Quality of Life in Southern Brazil

Abstract

Purpose:

This study examined the relationship between the breastfeeding efficacy and quality of life (QoL) in a sample of 89 mothers from southern Brazil. To the authors' knowledge, this is the first study to explore correlations between maternal QoL and breastfeeding efficacy in Brazil.

Methods:

Research participants completed the Portuguese version of the World Health Organization Quality of Life–BREF and Multicultural Quality of Life Index questionnaires. Breastfeeding efficacy was evaluated through the Breastfeeding Self-Efficacy Scale–Short Form (BSES-SF). Correlations between the scores of the QoL instruments and the BSES-SF were examined using Pearson product-moment correlation coefficients.

Results:

There were significant correlations among the scores of the two QoL questionnaires and the BSES-SF. Multiple regression analysis revealed that both QoL instruments significantly predicted BSES-SF scores. Neither socioeconomic status nor level of educational attainment was a significant predictor of breastfeeding efficacy.

Conclusions:

Introduction

Breastfeeding is a significant element in the maternal experience.^1,2 There has been a significant increment in the scientific knowledge of the benefits of breastfeeding in recent decades.³ Specific policies and guidelines now encourage health professionals to promote and protect breastfeeding at different societal levels.³ In 2001, the World Health Organization (WHO) endorsed the worldwide recommendation for breastfeeding to be continued while weaning foods are added after the initial 6-month period of exclusive breastfeeding.⁴

Breastfeeding is also known to produce a series of developmental and health benefits for the infant^3,5,6 and to favor a more fulfilling bonding experience between the mother and the baby.⁷ Breastfeeding and lactation also produce important maternal advantages,⁸ including decreased postpartum bleeding⁹ and incidence of type 2 diabetes¹⁰ as well as reduced risk of breast¹¹ and ovarian¹² cancers. For many women, the breastfeeding experience represents an intimate and fulfilling relationship with their babies. However, some mothers can experience distress and dysphoria during the breastfeeding period.^2,13

Multiple factors influence the perception of mothers about their breastfeeding experiences, including maternal physical and emotional heath, the health of the baby, the interplay with their extended family, their socioeconomic status, and environmental living conditions, as well as the amount of additional demands on the mother. Therefore, the breastfeeding experience is considered as an act molded by the prevailing sociocultural norms and economic conditions.^14–17

In addition to the variables mentioned above, during the postpartum and breastfeeding period, mothers tend to experience significant health changes, including the occurrence of several physical symptoms and disorders such as fatigue, headache, dyspareunia, hemorrhoids, and pain at multiple sites.¹⁸ Although these symptoms are frequently regarded as transient or inconsequential, they appear to be associated with significant functional impairment and with poor emotional status of the mother.¹⁹ In fact, some women face the recurrent demands from a breastfeeding child as a physically and emotionally exhausting experience,¹³ which also brings about sensations of loss of control and low self-esteem.²⁰ These challenges ultimately lead to guilty feelings and doubts about continuation of breastfeeding.²¹

In spite of the many factors that may interfere with the quality and frequency of the breastfeeding experience and the variable levels of maternal competency for breastfeeding experience, there is limited scientific evidence about the possible changes in quality of life (QoL) experienced by mothers during the breastfeeding period.

The present study aims to examine the relationship between the breastfeeding efficacy and QoL in a sample of mothers from southern Brazil. In this study, the scores of two QoL assessment tools are correlated with scores from a breastfeeding efficacy scale. To the authors' knowledge, this is the first study to explore correlations between maternal QoL and breastfeeding efficacy in Brazil.

Subjects and Methods

Participants were recruited from the University of Caxias do Sul General Hospital, Caxias do Sul, in southern Brazil between December 2004 and September 2005. The hospital is a higher education training facility and a regional referral center in obstetrics. In 2002, the hospital was designated as a Baby-Friendly facility based on the WHO Baby-Friendly Hospital Initiative.^22,23

Eligible participants were all hospitalized breastfeeding mothers who were able to read and understand Portuguese and had given birth to a healthy infant. Research volunteers were recruited via word of mouth by members of the research team, while still in hospital, in the days following delivery. A complete description of the research protocol was given to prospective participants. Mothers were excluded if they had a factor that could significantly interfere with breastfeeding, such as the birth of multiples or high-risk pregnancy (i.e., serious medical condition or known birth defect), or if the baby was not discharged back home with the mother. After initial screening, 101 women were potentially eligible to participate in this study and agreed to participate in the study. During the home visit interview, described below, 12 women were no longer breastfeeding because of several reasons. The final sample was therefore constituted by all mothers who were breastfeeding at the time of interview (n = 89).

Informed consent

This study was endorsed by the Institutional Ethics and Research Committee. All participants signed a consent form that declared their voluntary agreement with all the procedures involved in this project. Because a substantial number of patients were semi-illiterate, all patients completed the Portuguese version of the BSES–SF, MQLI, and WHOQOL-BREF questionnaires with minimal guidance from trained examiners, who in turn followed standardized instructional procedures.

Instruments

Breastfeeding Self-Efficacy Scale

The Breastfeeding Self-Efficacy Scale (BSES) is a 33-item, self-report instrument developed to assess breastfeeding confidence.²⁴ The BSES is an ordinal scale where all items are preceded by the phrase “I can always” and anchored with a 5-point Likert-type scale where 1 indicates “not at all confident” and 5 indicates “always confident.” All items are presented positively, and scores are summed to produce a range from 33 to 165, with higher scores indicating higher levels of breastfeeding self-efficacy. The BSES–Short Form (SF) was validated in Turkish,²⁵ Polish,²⁶ and Portuguese.²⁷

WHO QoL Assessment–BREF

The WHO QoL Assessment–BREF (WHOQOL-BREF) was developed by WHO as an abbreviated 26-item version of the WHOQOL-100 instrument. The WHOQOL-100 is used to measure quality of life across a variety of cultural settings.²⁸ The WHOQOL-BREF is divided into four domains: Physical, Psychological, Social Relationships, and Environment. Each domain score reflects an individual's perception of his or her quality of life in that particular area. Two items are examined separately: Question 1 (Q1) asks about an individual's overall perception of QoL, and question 2 (Q2) asks about an individual's overall perception of his or her health. The WHOQOL-BREF has been validated across a wide range of languages, including Portuguese.²⁹

Multicultural QoL Index

The Multicultural QoL Index (MQLI) is a self-administered questionnaire designed to measure QoL according to 10 items that include physical and emotional well-being, self-care, occupational and interpersonal functioning, community and services support, and personal and spiritual fulfillment as well as global perception of QoL. The Portuguese version of the MQLI has been tested in a mixed sample of patients and health professionals in Brazil.³⁰ Spanish,³¹ Chinese,³² and Korean³³ versions of the MQLI have also been validated. These studies have demonstrated that the MQLI is brief, easy to administer, internally consistent, and substantially reliable.³⁴

Socioeconomic status measurement scale

Research participants also completed a socioeconomic status (SES) scale that had been developed and tested in Brazil.³⁵ This instrument classified participants according to six socioeconomic strata: Lower-Lower Class, Upper-Lower Class, Lower-Middle Class, Middle Class, Upper-Middle Class, and Upper Class.

Statistical analysis

Demographic analysis evaluated the age, educational background, SES, number of previous pregnancies, and deliveries of research participants. To allow for comparative analyses, metrics from the various scales were converted to z scores and reverse-scaled so that all measures exhibited positive values as their highest possible scores. Three patients did not complete one question of the WHOQOL-BREF questionnaire (questions 5, 7, and 8), in which cases the mode was used as a substitute for the missing score. Relevant correlations among different assessment tools were examined using Pearson product-moment correlation coefficients. Analyses of variance were conducted among women from different SES groups. A one-way analysis of covariance was calculated to evaluate whether the mean scores of the MQLI and of each domain of the WHOQOL-BREF (dependent variables) may have varied across different SES levels (independent variable) after adjusting for educational background (covariate). Statistical analysis was conducted with SPSS^® software (SPSS, Inc., Chicago, IL).

Results

Demographic statistics

The mean age of our participants was 25.4 years (SD = 6.99), with ages ranging from 14 to 42 years. Women were classified according to Brazilian census criteria as white (n = 68; 76.4%), black (n = 9; 8%), and brown or Pardo (n = 13; 12.8%). Data on marital status revealed that 37% (n = 33) of the mothers were in de facto relationships (common-law marriages), 34% (n = 38) were married, 20% (n = 22) were single, and 2% (n = 2) were divorced. Most of the mothers (66.3%; n = 59) delivered vaginally, while 33.7% (n = 30) underwent a cesarean delivery. On average, research participants were interviewed 7.69 (±1.7 SD) weeks after delivery.

Most of the mothers (44%; n = 39) in the study were giving birth to their first child, while 29% (n = 26) gave birth to their second child, and 13% (n = 12) gave birth to their fourth or subsequent baby. At the time of interview, 69 participants (77.5%) were exclusively breastfeeding, whereas 20 mothers (22.5%) were partially breastfeeding. The SES of women in the sample was distributed as follows: 1% (n = 1) was classified in the Lower-Lower Class, 15% (n = 13) in the Upper-Lower Class, 72% (n = 64) in the Lower-Middle Class, and 12% (n = 11) in the Middle Class. No participants were categorized as being in the Upper-Middle and Upper Classes. One participant (1%) had a university degree, four participants (4.5%) reported a partial university education, 18 participants (20%) had completed high school, 23 mothers (26%) had a partial high school education, five mothers (6%) had completed primary school, and 38 mothers (43%) had not completed primary school.

QoL

The mean MQLI score was 76.45 (SD = 15.56). The WHOQOL-BREF mean scores (SD) per each subarea were as follows: Physical domain, 70.85 (16.43); Psychological domain, 63.92 (15.31); Social domain, 67.18 (18.03); and Environment domain, 60.47 (11.78). Results from Q1 revealed that mothers rated their overall QoL as follows: very good (9%), good (61.8%), neither poor nor good (24.7%), poor (2.2%), and very poor (2.2%). In Q2, participants rated their level of satisfaction with their health as follows: very satisfied (14.6%), satisfied (51.7%), neither satisfied nor dissatisfied (20.2%), dissatisfied (11.2%), and very dissatisfied (2.2%).

Breastfeeding efficacy

The mean BSES-SF score was 63.51 (SD = 6.25). The minimum BSES-SF score was 43, whereas the maximum score was 70. The mean score (SD) of primiparous women was 63.74 (6.6), while multiparous women's mean score was 63.49 (6).

QoL and breastfeeding efficacy

As demonstrated in Table 1, there were significant correlations (r) between the overall BSES-SF scores and the scores of the MQLI as well as the score of each subarea of the WHOQOL-BREF. All significant correlations displayed size effects above the 0.3 range. A comparison was made between QoL scores of mothers who exclusively breastfed and those who opted for a combined approach (breastfeeding and formula). The results of the Social Relationships domain of the WHOQOL-BREF revealed a significant difference between the two groups of mothers regarding their breastfeeding modalities: t (87) = 2.55, p = 0.013. However, in all other domains of the WHOQOL-BREF there were no significant differences between the two groups. Furthermore, there was a significant difference of QoL scores according to the MQLI between mothers who exclusively breastfed and those who combined breastfeeding with formula: t (87) = 2.27, p = 0.03.

Table 1.

Correlations (r) Between the Overall Breastfeeding Self-Efficacy Scale–Short Form Scores and the Scores of the Multicultural Quality of Life Index and the Four Subareas of the World Health Organization Quality of Life-BREF Instrument

		WHOQOL-BREF
BSES-SF	MQLI	Physical (D1)	Psychological (D2)	Social (D3)	Environment (D4)
r	0.52^a	0.48^a	0.35^a	0.37^a	0.32^a
p	<0.001	<0.001	0.001	<0.001	0.002

Correlation is significant at the 0.01 level (two-tailed).

BSES-SF, Breastfeeding Self-Efficacy Scale–Short Form; MQLI, Multicultural Quality of Life Index; WHOQOL-BREF, World Health Organization Quality of Life Assessment-BREF.

Breastfeeding efficacy, perceptions of QoL, and health status

An analysis of variance was conducted to explore differences of BSES-SF means according to different levels of satisfaction revealed in the independent Q1 of the WHOQOL-BREF, which asks about an individual's overall perception of QoL. The mean BSES-SF score (SD) according to each level of satisfaction was as follows: very poor, 62.5 (4.94); poor, 61 (12.73); neither poor nor good, 62.32 (6.21); good, 63.58 (6.5); and very good, 67.13 (1.81). There was no significant difference of BSES-SF scores according to different levels of perception of quality of life as revealed above, with F_4,84 = 0.96, p = 0.43.

Another analysis of variance was conducted to explore differences of BSES-SF means according to different levels of satisfaction revealed in the independent Q2 of the WHOQOL-BREF, which asks about an individual's overall perception of their health. The mean BSES-SF score (SD) according to each level of satisfaction was as follows: very dissatisfied, 57.5 (12.02); dissatisfied, 60.10 (8.42); neither satisfied nor dissatisfied, 61.39 (6.42); satisfied, 64.78 (5.34); and very satisfied, 65.46 (4.75). There was a significant difference of BSES-SF scores according to different levels of overall perception of health, with F_4,84 = 2.72, p = 0.03.

QoL, breastfeeding efficacy, SES, and education

A multiple regression analysis was conducted to evaluate how well the QoL questionnaires predicted breastfeeding efficacy (BSES-SF scores). These findings are summarized in Table 2. Additional predicting factors were SES and level of educational attainment. The MQLI significantly predicted BSES-SF scores: R² = 0.27, F_1,87 = 32.51, p < 0.001. Similarly, all subareas of the WHOQOL-BREF taken together significantly predicted BSES-SF scores: R² = 0.25, F_4,84 = 7, p < 0.001. However, SES per se did not account for a significant proportion of breastfeeding efficacy variance: R² = 0.006, F_1,87 = 0.52, p = 0.47. Likewise, level of educational attainment did not account for a significant proportion of BSES-F variance: R² = 0.001, F_1,87 = 0.67, p = 0.8.

Table 2.

Predictive Influence of Quality of Life, SocioEconomic Status, and Level of Educational Attainment in the Breastfeeding Efficacy (Breastfeeding Self-Efficacy Scale–Short Form Scores) of 89 Mothers in Southern Brazil

Predictor, controlled variable(s)	R²	Significance
MQLI
—	0.27	p < 0.001
SES	0.26	p < 0.001
SES + education	0.27	p < 0.001
WHOQOL-BREF
—	0.25	p < 0.001
SES	0.24	p < 0.001
SES + education	0.25	p < 0.001
SES
—	0.0006	p = 0.47
Education
—	0.001	p = 0.8

A dash indicates no controlled variable.

SES, socioeconomic status.

Subsequent regression analyses were conducted having the MQLI scores as the first predictor and the SES and/or the level of educational attainment as the second predictor. After controlling for the effects of the SES status, both the MQLI (R² = 0.26, F_1,86 = 31.48, p < 0.001) and the WHOQOL-BREF (R² = 0.24, F_1,86 = 6.77, p < 0.001) scores significantly predicted the BSES-SF scores. In the same way, after controlling for the effects of the SES status and educational attainment, both the MQLI scores (R² = 0.27, F_1,86 = 32.17, p < 0.001) and the WHOQOL-BREF scores (R² = 0.25, F_4,86 = 6.89, p < 0.001) significantly predicted breastfeeding efficacy in the sample.

Discussion

The demographic results indicate that the majority of women evaluated in this study are white, are in their mid-20s in age, possess limited educational background, and come from a lower SES echelon of the Brazilian society. Most of these mothers were living in a de facto relationship and breastfeeding her first baby following a vaginal delivery. The sample was, therefore, representative of the typical women seeking obstetric care in a public health service in southern Brazil. Members of the lower echelons of the Brazilian society constitute the usual population segment assisted in the Brazilian public healthcare system.³⁶

The majority of participants assessed in this study reported “good” levels of QoL according to the WHOQOL-BREF questionnaire. In addition, most of the participants were “satisfied” with their health status, according to the second independent question of the WHOQOL-BREF questionnaire. Furthermore, the significant correlations (p < 0.01) between the MQLI and all of the WHOQOL-BREF domains, as well as the large size effect of these associations, further confirm the symmetry between the two QoL measurement tools. The significant correlation among the scores of the two quality of life questionnaires and the BSES-SF indicates an association between self-rated maternal health status and breastfeeding efficacy.

The results from the several subareas of the WHOQOL-BREF, as reported here, show some congruence with cross-sectional data obtained from a mixed sample of healthy volunteers and patients in Brazil, which was part of the WHOQOL-BREF international trials carried out in 23 countries (n = 11,830).³⁷ In addition, the mean QoL scores revealed by the MQLI in this study were slightly higher than the MQLI score of a subsample of healthcare professionals (n = 30) who served as a control group during the initial trials of the MQLI in southern Brazil.³⁰ Therefore, according to both QoL tools used in this study, postpartum women in this area of southern Brazil reported favorable QoL parameters.

The results of this study, therefore, indicate that many women sustain reasonable levels of QoL despite the challenges they may encounter during the postpartum period. In fact, a study using the Maternal Postpartum QoL instrument to assess the QoL of 184 mothers revealed that the mean QoL scores increased from the first week postpartum to the third week, which indicates that mothers may feel better as time passes during the postpartum.³⁸ Women recovering from delivery and experiencing the demands of a new baby, including breastfeeding, face a number of limitations in terms of their physical mobility, professional performance, and social lives. The challenges are usually more prominent during the initial phases of the postpartum period. Considering that, on average, research participants were interviewed more than 7 weeks after delivery, it is possible that during the earlier phase of the postpartum period, mothers would report lower levels of QoL. Studies with a prospective design with multiple assessments initiating prior to delivery and with subsequent evaluation in different stages of the postpartum period are needed to elucidate whether QoL increases progressively after delivery.

On the other hand, a study conducted with 103 postpartum women, in which women completed the Mother-Generated Index, mothers in the highest score quartile group reported a sense of fulfillment and high self-esteem as well as satisfactory relationships with family members.³⁹ Therefore, it is also possible that delivery and maternity bring about feelings of joy and satisfaction, which may influence favourably the overall sense of well-being and QoL.

The mean BSES-SF score in our Brazilian sample (63.5) was higher than the mean score reported in the Polish (55.6) and Turkish (60.1) samples, but inferior to the scores of the Chinese (118.8) and the Spanish (131.8) samples. The mean score found in the Brazilian sample is therefore within reasonable parameters of distribution, which suggest that Brazilian women present intermediate levels of breastfeeding efficacy.

This study also endeavors to contribute to the advancement of knowledge in maternal QoL during the postpartum period, especially in the context of a vulnerable population—women of low SES—in a developing economy such as Brazil. A trend towards lesser QoL scores in lower socioeconomic strata was observed in a study in which 195 women were assessed using the Mother-Generated Index questionnaire.⁴⁰ The subscale related to SES was also identified as a lower scoring area in the Maternal Postpartum QoL questionnaire when mothers were interviewed during the first week of postpartum.³⁸ In addition, studies conducted in developing countries have reported an inverse relationship between SES and successful breastfeeding experiences.⁴¹ In fact, studies conducted with mothers of lower SES demonstrated that the personal and social factors of mothers tend to be more salient than their formal knowledge about the breastfeeding experience in determining whether or not a woman will breastfeed her baby.^16,42

Apart from SES, other factors such as older age and low levels of educational achievement have been correlated with low QoL standards,⁴³ while another study indicated that variables such as marital status, educational level, and income did not influence WHOQOL-BREF scores in a sample of elderly volunteers recruited from public community health centers in Brazil.⁴⁴

In spite of all the evidence mentioned above, in the current study, neither SES nor level of educational attainment was a significant predictor of breastfeeding efficacy. In addition, SES and educational attainment did not influence the predictive effect of QoL in predicting breastfeeding efficacy. These results indicate that, although SES and educational background are salient variables in health and social research, these factors did not exert any moderation effect on the predictive significance of QoL on levels of breastfeeding efficacy.

Conclusions

The results from the present study indicate that breastfeeding efficacy is significantly related to QoL among mothers in southern Brazil. The association between QoL and breastfeeding efficacy appears to be independent from any effect of SES or level of educational achievement. The results described appear to suggest that the assessment of maternal QoL may be also helpful to gauge the breastfeeding efficacy of mothers. Additional studies are needed to further test the usefulness of QoL measures as predictive measures of breastfeeding efficacy within a larger sample size. Considering the interactions between neuroendocrine activity and emotional status during the postpartum period,⁴⁵ it would be relevant to investigate the possible relationships between serum levels of oxytocin and breastfeeding efficacy and satisfaction with life in general.

The sample of postpartum women evaluated in this investigation presented favorable QoL parameters. This investigation also revealed that maternal QoL and breastfeeding efficacy both present significant correlation during the postpartum period. Finally, the results from the present study indicate that QoL measures and breastfeeding efficacy are valid and researchable topics in community healthcare programs.

Footnotes

Disclosure Statement

No competing financial interests exist.

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