Reproductive value (not to be confused with breeding value) is a concept in demography and population genetics that represents the discounted number of future girl children that will be born to a woman of a specific age. Ronald Fisher first defined reproductive value in his 1930 book The Genetical Theory of Natural Selection where he proposed that future offspring be discounted at the rate of growth of the population; this implies that  sexually reproductive value measures the contribution of an individual of a given age to the future growth of the population.