Using experimental methods researchers have found support for: childhood stress (§ 6b) and father absence (§ 6c) lowering preferred age
at first birth and increasing sexual risk taking [45,53]; attachment style (§ 6e) influencing parenthood - related thoughts [60]; cultural
norms (§ 6m) discouraging reproduction outside stable unions [12]; women's reproductive autonomy (§ 6i) influencing their fertility preferences [47]; paternity uncertainty (§ 6j) discouraging parental investment by men [55]; high
cost of children (§ 6l) encouraging delayed reproduction and lower fertility [36,47]; resource stress and limitation (§ 6o) affecting mating preferences [12,36,40,51]; and mortality risk and salience (§ 6p) encouraging a
greater interest in children, earlier reproduction and higher fertility [6,41,42,45,57 — 59].