PIP: This is a 1st attempt at an explicitly intertemporal, microeconomic theory of the distribution of births over a woman's fertile period. The main results are that: 1) the optimal time-profile will satisfy the Hotelling rule for the depletion of a natural resource (in the present case of the women's stock of human capital at marriage); and 2) under certain simplifying assumptions, women with "high" initial endowments of human capital will have all their children in the 1st part of married life and then return to full-time employment, while women with "low" initial endowments will spread childbearing more evenly over the fertile period. It must also be pointed out that the characteristics of the optimal fertility profile might be different if utility depended directly on the profile itself--e.g., if the quality of children increased with the interval between the pregnancies, as assumed in the literature on birth spacing.