The desire for a son could mean Nepali mothers stop breastfeeding infant daughters sooner, says new research.
Girls in Nepal are breastfed for fewer months than boys on average, with girls with older sisters but no brothers being the most disadvantaged, says the study.
And this shorter breastfeeding time is linked to a greater risk of death for Nepali infants in the study.
'Gender, Nutritional Disparities, and Child Survival in Nepal' by Dr Jasmine Fledderjohann, of Lancaster University, and Dr Melanie Channon,from the University of Bath, is published in the journal, BMC Nutrition, today.
And, says the study, the desire to have a son may influence breastfeeding duration because if a woman has not had a son, she may feel greater pressure to try to conceive again in the hopes of having a boy.
The researchers explain that breastfeeding has a known contraceptive effect, and women who want to try for another child may stop breastfeeding sooner than women who are not trying to conceive again.
The researchers found that girls had a shorter duration of breastfeeding on average than boys. And, importantly, it wasn't just the child's gender, but also the gender of any older siblings that mattered.
Girls with only older sisters were at a greater disadvantage.
Son preference has long been documented as an important factor in gender differences in health outcomes Nepal and elsewhere in South Asia.
Sex-selective abortions and high ratios of male births have received particular attention in previous research. Less well-understood are gender differences in children's nutrition in early life, and whether, and how, such differences are linked to child survival.
Using the most recently available nationally representative data, which were collected every five years over a 20-year period, the research team investigated whether gender differences in mortality differed over time and between regions.
The research team found that, over the 20-year period of the study, mortality outcomes had greatly improved across the board.
However, these improvements were faster for boys than for girls, meaning that, while all children faced a lower risk of mortality as time went on, the relative gap between boys and girls grew.
Girls in wealthy urban areas fared the worst in terms of mortality rates.
Because good nutrition is tremendously important for children's survival and growth in the first five years of life, the team also looked at whether girls were disadvantaged in feeding practices in infancy and early childhood and, if so, whether gendered feeding practices were associated with higher risks of mortality.
They looked for gender differences in children's consumption in the preceding 24 hours of 16 categories of food items, consumption of an adequately diverse diet, whether children were breastfed within 1 hour of birth, and for how long children were breastfed.
They found no evidence of gender gaps in terms of food consumption and dietary diversity. The only gender gaps they found were in breastfeeding duration.
The research showed that firstborn children-both boys and girls-had a lower breastfeeding duration than children who had older siblings. As most Nepali women report wanting more than one child, this is consistent with the idea that women stop breastfeeding earlier to try to conceive.
But among children who had older siblings, children with older brothers tended to fare better, while girls who had only older sisters (no brothers) had the shortest breastfeeding duration.
The research team also considered whether breastfeeding duration mattered for mortality, and found that, indeed, breastfeeding duration had an important protective effect.
Lead researcher Dr Jasmine Fledderjohann said: "The study is important because it highlights that son preference and its manifestation in families is not a straightforward matter of universal discrimination against girls. Rather, son preference may impact girls' health and well-being in complex, nuanced ways that are linked not only to their own gender, but also to family composition."
