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Associate Professor of Sociology, University of Virginia 

No Evidence of Mother Discrimination in Columbia

Bryce J. Christensen and Nicole M. King

Many scholars interested in the relationship between work and family have studied the “motherhood penalty,” the supposed cut in wages that motherhood tends to bring. Luis Fernando Gamboa and Blanca Zuluaga, researchers from Columbia, have found, however, that at least for mothers in Columbia, much of the so-called motherhood penalty is actually explained by traits other than motherhood itself.

Although the motherhood penalty has been studied rigorously in the U.S. and in other developed countries around the world, relatively few have undertaken similar work in developing countries and specifically in Latin America. One such study which the authors reference (Olarte and Peña, 2010) found a large wage gap of 9.4% between mothers and non-mothers, of which 8% “was explained by unobservable factors that might include discrimination against mothers.” Such discrimination, Olarta and Peña suspected, may be higher in countries that had more traditional views of women in the workplace.

Gamboa and Zuluaga used the same cross-sectional database (the Columbia Living Standard Survey of 2008) as did Olarte and Peña, but a different method of decomposing the wage gap which “limit[s] the comparison only to those women with comparable characteristics.” In addition, for those women who could not be “matched” when using the original matching variables of age and region, the authors used a five-step algorithm to construct a synthetic, matching non-mother to better compare these women.

Gamboa and Zuluaga found that in their sample, 48.6% of mothers and 48% of non-mothers were employed. “As expected,” the researchers reported, “mothers earned, on average, lower wages than women with no children.” Self-employed women, both mothers and non-mothers, received the lowest wages. The researchers also found that only 18% of non-mothers were self-employed, compared to about one-third of mothers, indicating that mothers find the rewards of remaining at home much greater than do non-mothers. Public employees received the highest wage, and there was no statistically significant difference in the wages between mothers and non-mothers in the public sector.

Overall, however, the researchers found a much smaller wage gap than had been discovered before: “Results showed that women with no children earned, on average, 1.73% more than mothers.” When using matching variables to attempt to explain any part of this wage gap that could not be explained by other factors, the researchers discovered that one in particular—education level—reduced the wage gap to non-significance. Instead of motherhood per se, much of the difference in wages between mothers and non-mothers seems to be related to the differences in education levels between those two groups. The researchers conclude, “we could not say, based on our exercise, that there was evidence of discrimination against mothers in Columbia.”

The researchers suggest that beside education levels, the wage gap may also be driven by mothers who deliberately choose jobs with lesser wages but greater flexibility, as is evidenced by the larger numbers of self-employed mothers. They suggest that in the absence of any evidence of wage discrimination against mothers, Columbia should instead consider policies that would promote education, especially for poor women, and also increase time flexibility at work.

These results demonstrate not that employers discriminate against mothers in Latin America, but instead that more highly educated women in Latin America were not mothers. What would have been interesting, and something the researchers do not report on, is what kind of difference marriage makes on a women’s education levels. That is, does the absence of a husband make it more difficult for women to complete their education? Are there more married, educated, working mothers than non-married, educated, working mothers? One would suspect as much, but on this, the research is silent.

(Luis Fernando Gamboa and Blanca Zuluaga, “Is There a Motherhood Penalty? Decomposing the Family Wage Gap in Colombia,” Journal of Family and Economic Issues [2013]. doi: 10.1007/s10834-012-9343-y.)