Low fertility, including below replacement fertility, is usually correlated with later marriage and both are associated with common cause factors, such as increasing education and workforce participation of women, as well as with development more generally (Jones, 2007). However, in the division of Khulna in South-Western Bangladesh, very low overall fertility rates of less than 2 births per woman coexist with very early patterns of marriage. This region reports some of the highest levels of child marriage with large numbers of girls getting married as early as 14 or 15 years even while fertility is below replacement level (NIPORT, Mitra and Associates, and Macro International, 2009). Such a distinctive pattern of transition, in which fertility change has occurred even while early marriage persists, is important to understand as it can have important demographic implications.