The study of women's magazines since the 1950s found that advertisements focus on an idealised image of the "knowing mother," who is exhorted to put all their expertise to use in the service of the family.
Researchers at the University of Sydney, Lancaster University, the University of Edinburgh, Melbourne's Monash University and St Gallen University in Switzerland looked at advertisements published in Australian Women's Weekly and the UK's Good Housekeeping between 1950 and 2010.
Their findings, published in the Journal of Consumer Culture, indicate that while the image of mothers changed over the period from consumers needing expert guidance to women able to draw on their own knowledge and expertise when buying on behalf of the family, women's knowledge is always used first to care for their families.
Assumptions about their responsibilities endured as advertisers repeatedly positioned mothers in relation to their domestic tasks, such as cooking and cleaning and using their knowledge for family purposes rather than their own gain or professional pursuits.
"Knowing how to consume correctly for the family is represented as a major definer of female identity," said report lead author Associate Professor Teresa Davis, of the University of Sydney Business School.
"The caring mother is one of the most recurring images of femininity in post-war advertising," Associate Professor Davis said.
Representations of the good mother are especially evident in relation to her consumption for the family and always using her knowledge to cook, care and clean 'correctly'.
"The advertisements we looked at place an emphasis on what mothers can, should and need to know, inviting readers to compare themselves with the domestic ideal represented in the advertisements."
"Despite shifts in attitudes that appear to share the role of caring within a family, there exists an enduring assumption that mothers should be responsible," she added. "Adverts increasingly position mothers as needing to acquire ever more expertise and skills to professionalise their mothering, but only represent them as using this knowledge for selfless maternal purpose."
While the mothers' priorities have remained largely unchanged, the researchers did find a shift over the 60 year period in the way that mothers were portrayed.
In the 1950s, according to the journal article, adverts show mothers following the advice of (mainly male) experts such as doctors, celebrities and psychologists, on how to "consume correctly" and care for their children.
Mothers would decide which brands of toothpaste, vitamins or clothing they should buy, with their choices legitimised by a doctor's approval. Images highlight the pressures of intensive mothering, with the knowledgeable mother one who happily sacrifices her time to make the right decisions for her family.
The theme continued into the 1960s and 1970s, with maternal knowledge reinforced by scientific statements and expert opinions. While professional and domestic lives intertwine in the 1980s and 1990s, mothers use their professional skills and knowhow to consume efficiently for the family.
By 2000 and 2010, the mother becomes the expert, no longer passively following instructions but rather, negotiating her way around complex scientific facts and sifting through claims about subjects such as genetically modified foods.
She needs to know enough to be able to question experts, however, and the adverts still represent mothers as possessing and striving for this knowledge primarily for the protection of their families and children.
"Through the decades we studied, we can trace the transformation of mothers from someone informed by experts about how to consume for her family to someone who is an expert herself," said co-author, Professor Margaret K. Hogg, of Lancaster University Management School.
"There is a major shift in recognising a woman's place as a holder of scientific knowledge. This is not just around the family, but also on issues such as the environment, sustainability, illness and well-being."
This use of knowledge for the family's benefit is a common theme throughout the advertisements studied by the researchers in both Good Housekeeping and Australian Women's Weekly, be they for washing powder, vitamin supplements, tissues or disinfectants.
"In all instances, the representation of the knowing mother is presented as what mothers should aspire to, and this is an enduring vision across seven decades and two continents," said co-author Professor David Marshall, of the University of Edinburgh Business School.
"Although knowledge changes over the decades, it remains bent towards the pursuit of a selfless maternal ideal, strengthening gender stereotypes and the traditional hegemony," Professor Marshall concluded.
Read the report, The knowing mother: Maternal knowledge and the reinforcement of the feminine consuming subject in magazine advertisements, at SAGE Journals.