Journal of Population Economics

, Volume 24, Issue 3, pp 1071–1100 | Cite as

The effects of motherhood timing on career path

  • Amalia R. MillerEmail author
Original Paper


This paper estimates the effects of motherhood timing on female career path, using biological fertility shocks to instrument for age at first birth. Motherhood delay leads to a substantial increase in earnings of 9% per year of delay, an increase in wages of 3%, and an increase in work hours of 6%. Supporting a human capital story, the advantage is largest for college-educated women and those in professional and managerial occupations. Panel estimation reveals both fixed wage penalties and lower returns to experience for mothers, suggesting that a “mommy track” is the source of the timing effect.


Fertility timing Female wages Family gap 

JEL Classification

J31 J13 K31 



I thank Susan Athey, B. Douglas Bernheim, John Pencavel, and Antonio Rangel for their excellent advising. I am grateful to the editor and anonymous referees of this journal, to Eli Berman, Katie Carman, Victor Fuchs, Larry Katz, Edward Lazear, Laura Lindsey, David Matsa, Carmit Segal, Marianne Simonsen, Scott Stern, Ed Vytlacil, and Geoff Warner, and to seminar participants at Arizona, Duke, McGill, Michigan State, Queens, UC-San Diego and Virginia for helpful comments. The Koret Foundation and the Stanford Institute for Research on Women and Gender provided generous financial support.

Supplementary material

148_2009_296_MOESM1_ESM.pdf (61 kb)
Supplementary Figure (PDF 48 KB)


  1. Albrecht JW, Edin PA, Sundström M, Vroman SB (1999) Career interruptions and subsequent earnings: a reexamination using Swedish data. J Hum Resour 34(2):294–311CrossRefGoogle Scholar
  2. Alonzo AA (2002) Long-term health consequences of delayed childbirth. Women’s Health Issues 12(1):37–45CrossRefGoogle Scholar
  3. Amuedo-Dorantes C, Kimmel J (2005) The motherhood wage gap in the United States: the importance of fertility delay. Rev Econ Household 3(1):17–48CrossRefGoogle Scholar
  4. Angrist JD, Evans WN (1998) Children and their parents’ labor supply: evidence from exogenous variation in family size. Am Econ Rev 88(3):450–477Google Scholar
  5. Atkinson R (2003) Putting parenting first: why it’s time for universal paid leave. Policy Report, Progressive Policy InstituteGoogle Scholar
  6. Baum CL (2002) The effect of work interruptions on women’s wages. Labour 16(1):1–37CrossRefGoogle Scholar
  7. Blackburn MKL, Bloom DE, Neumark D (1993) Fertility timing, wages, and human capital. J Popul Econ 6(1):1–30CrossRefGoogle Scholar
  8. Blau FD (1998) Trends in the well-being of American women, 1970–1995. J Econ Lit 36(1):112–165Google Scholar
  9. Bronars SG, Grogger J (1994) The economic consequences of unwed motherhood: using twin births as a natural experiment. Am Econ Rev 84(5):1141–1156Google Scholar
  10. Browning M (1992) Children and household economic behavior. J Econ Lit 30(3):1434–1475Google Scholar
  11. Budig MJ, England P (2001) The wage penalty for motherhood. Am Sociol Rev 66(2):204–225CrossRefGoogle Scholar
  12. Caucutt EM, Guner N, Knowles J (2002) Why do women wait? Matching, wage inequality, and the incentives for fertility delay. Rev Econ Dyn 5(4):815–855CrossRefGoogle Scholar
  13. Chandler TD, Kamo Y, Werbel JD (1994) Do delays in marriage and childbirth affect earnings? Soc Sci Q 75(4):839–853Google Scholar
  14. Chen R, Morgan SP (1991) Recent trends in the timing of first births in the United States. Demography 28(4):513–533CrossRefGoogle Scholar
  15. Chen V (2003) Cracks in the ceiling. American Lawyer 25(6)Google Scholar
  16. Cramer J (1980) Fertility and female employment: problems of causal direction. Am Sociol Rev 45(2):167–190CrossRefGoogle Scholar
  17. Cristia JP (2008) The effect of a first child on female labor supply: evidence from women seeking fertility services. J Hum Resour 43(3):487–510Google Scholar
  18. Crittenden A (2002) The price of motherhood: why the most important job in the world is still the least valued. Holt, New YorkGoogle Scholar
  19. Dankmeyer B (1996) Long run opportunity—costs of children according to education of the mother in the Netherlands. J Popul Econ 9(3):349–361CrossRefGoogle Scholar
  20. Ellwood D, Wilde T, Batchelder L (2004) The mommy track divides: the impact of childbearing on wages of women of different skill levels. Working Paper, Russell Sage FoundationGoogle Scholar
  21. Fuchs V (1988) Women’s quest for economic equality. Harvard University Press, CambridgeGoogle Scholar
  22. Gustafsson S (2001) Optimal age at motherhood: theoretical and empirical considerations on postponement of maternity in Europe. J Popul Econ 14(2):225–247CrossRefGoogle Scholar
  23. Hewlett SA (2002) Creating a life: professional women and the quest for children. Hyperion, New YorkGoogle Scholar
  24. Hofferth SL (1984) Long-term economic consequences for women of delayed childbearing and reduced family size. Demography 21(2):141–155CrossRefGoogle Scholar
  25. Hotz VJ, Mullin CH, Sanders SG (1997) Bounding causal effects using data from a contaminated natural experiment: analysing the effects of teenage childbearing. Rev Econ Stud 64(4):575–603CrossRefGoogle Scholar
  26. Hotz VJ, McElroy SW, Sanders SG (2005) Teenage childbearing and its life cycle consequences: exploiting a natural experiment. J Hum Resour 60(3):683–715Google Scholar
  27. Imbens GW, Angrist JD (1994) Identification and estimation of local average treatment effects. Econometrica 62(2):467–475CrossRefGoogle Scholar
  28. Joshi H, Paci P, Waldfogel J (1999) The wages of motherhood: better or worse? Camb J Econ 23(5):543–564CrossRefGoogle Scholar
  29. Klepinger D, Lundberg S, Plotnick R (1999) How does adolescent fertility affect the human capital and wages of young women? J Hum Resour 34(3):421–448CrossRefGoogle Scholar
  30. Korenman S, Neumark D (1992) Marriage, motherhood and wages. J Hum Resour 27(2):233–255CrossRefGoogle Scholar
  31. Light A, Ureta M (1995) Early-career work experience and gender wage differentials. J Labor Econ 13(1):121–154CrossRefGoogle Scholar
  32. Loughran DS, Zissimopoulos JM (2009) Why wait?: the effect of marriage and childbearing on the wages of men and women. J Hum Resour 44(2):326–349Google Scholar
  33. Maranto G (1995) Delayed childbearing. Atl Mon 275(6):55Google Scholar
  34. Mason MA, Goulden M (2002) Do babies matter? The effect of family formation on the lifelong careers of academic men and women. Acad Bull Am Assoc Univ Profr 88(6):21–27Google Scholar
  35. Merck Manual of Diagnosis and Therapy (1999) Abnormalities of pregnancy, 17th edition, chapter 252.
  36. Miller AR (2009) Motherhood delay and the human capital of the next generation. Am Econ Rev 99(2):154–58CrossRefGoogle Scholar
  37. Mincer J, Ofek H (1982) Interrupted work careers: depreciation and restoration of human capital. J Hum Resour 17(1):3–24CrossRefGoogle Scholar
  38. Mincer J, Polachek S (1974) Family investments in human capital: earnings of women. J Polit Econ 82(2):S76–S108CrossRefGoogle Scholar
  39. Nielsen HS, Simonsen M, Verner M (2004) Does the gap in family-friendly policies drive the family gap? Scand J Econ 106(4):721–744CrossRefGoogle Scholar
  40. Regan L (2001) Miscarriage: what every woman needs to know. Orion Books, LondonGoogle Scholar
  41. Ruhm CJ (1997) The family and medical leave act. J Econ Perspect 11(3):175–186Google Scholar
  42. Segal C (2006) Motivation, test scores, and economic success. Working Paper, Harvard Business SchoolGoogle Scholar
  43. Simonsen M, Skipper L (2006) The costs of motherhood: an analysis using matching estimators. J Appl Econ 21(7):919–934CrossRefGoogle Scholar
  44. Taniguchi H (1999) Work and family-the timing of childbearing and women’s wages. J Marriage Fam 61(4):1008–1020CrossRefGoogle Scholar
  45. Waldfogel J (1998) Understanding the ‘family gap’ in pay for women with children. J Econ Perspect 12(1):137–156Google Scholar
  46. Waldfogel J (1999) Family leave coverage in the 1990s. Mon Labor Rev 122(10):13–21Google Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Department of EconomicsUniversity of VirginiaCharlottesvilleUSA

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