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The Family Gap in Wages: What Wombmates Reveal


  • Simonsen, Marianne

    () (Aarhus University)

  • Skipper, Lars

    () (KORA - Danish Institute for Local and Regional Government Research)


We shed new light on the effects of having children on hourly wages by exploiting access to data on the entire population of employed same-sex twins in Denmark. Our second contribution is the use of administrative data on absenteeism; the amount of hours off due to holidays and sickness. Our results suggest that childbearing reduces female hourly wages but the principal explanation is in fact mothers' higher levels of absence. We find a positive wage premium for fathers.

Suggested Citation

  • Simonsen, Marianne & Skipper, Lars, 2009. "The Family Gap in Wages: What Wombmates Reveal," IZA Discussion Papers 4650, Institute for the Study of Labor (IZA).
  • Handle: RePEc:iza:izadps:dp4650

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    References listed on IDEAS

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    1. repec:ilo:ilowps:487376 is not listed on IDEAS
    2. Fazeer Rahim, 2014. "Work-family attitudes and career interruptions due to childbirth," Review of Economics of the Household, Springer, vol. 12(1), pages 177-205, March.
    3. Nizalova, Olena Y. & Sliusarenko, Tamara & Shpak, Solomiya, 2016. "The motherhood wage penalty in times of transition," Journal of Comparative Economics, Elsevier, vol. 44(1), pages 56-75.
    4. Joseph, Olivier & Pailhé, Ariane & Recotillet, Isabelle & Solaz, Anne, 2013. "The economic impact of taking short parental leave: Evaluation of a French reform," Labour Economics, Elsevier, vol. 25(C), pages 63-75.
    5. Grimshaw, Damian. & Rubery, Jill., 2015. "The motherhood pay gap : a review of the issues, theory and international evidence," ILO Working Papers 994873763402676, International Labour Organization.

    More about this item


    twins; fertility; wages;

    JEL classification:

    • J13 - Labor and Demographic Economics - - Demographic Economics - - - Fertility; Family Planning; Child Care; Children; Youth
    • J24 - Labor and Demographic Economics - - Demand and Supply of Labor - - - Human Capital; Skills; Occupational Choice; Labor Productivity
    • J31 - Labor and Demographic Economics - - Wages, Compensation, and Labor Costs - - - Wage Level and Structure; Wage Differentials
    • J71 - Labor and Demographic Economics - - Labor Discrimination - - - Hiring and Firing

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