The article discusses the existence and outlook of an evolved desire to have children. Twin studies have found a genetic basis for conscious attempts to get pregnant. This heritable disposition increasingly affects societies of wide female reproductive choice (Kohler et al 1999). Based on 106 stories written by Finnish women in 2006, I analyse the symptoms, triggers and behaviour related to longing for babies. I suggest that a strong longing for first or subsequent children is an affective incentive of growing importance in low-fertility societies. Female desire for babies appears in two main forms: as part of a generally care-oriented personality and as a sudden, surprising and largely physical longing. The first type conforms to previous research on nurturing (Miller 1986; Foster 2000) while the second type has not been much studied yet. For both types, a desire to have children is often related to physical age, falling in love, previous pregnancies and to exposure to babies of kin and peers. I discuss evolutionary explanations and suggest that longing for babies may have evolved not only as a by-product of finding care pleasurable, but also as part of mate selection and as a consequence of hormonal changes induced by couple formation and ageing.