“…In addition, reproductive hormone production appears to be sensitive to other major life stages, including parenthood. Changes in estradiol and progesterone levels are important for both achieving and maintaining pregnancy (Ellison, 2008; Ellison, Peacock, & Lager, 1986; Hall & Guyton, 2011), while testosterone levels may decrease in fathers (although the degree of this decline may depend on the amount of time fathers spend interacting with their children) (Gettler, McDade, Agustin, Feranil, & Kuzawa, 2014; Gettler, McDade, Feranil, & Kuzawa, 2011; Gray, Straftis, Bird, McHale, & Zilioli, 2020; Grebe, Sarafin, Strenth, & Zilioli, 2019; Muller, Marlowe, Bugumba, & Ellison, 2009).…”