baker notes that "most observers of the lincoln marriage have been impressed with their sexuality". some "male historians" suggest that the lincolns' sex life ended either in 1853 after their son tad's difficult birth or in 1856 when they moved into a bigger house, but have no evidence for their speculations. baker writes that there are "almost no gynecological conditions resulting from childbirth" other than a prolapsed uterus (which would have produced other noticeable effects on mrs. lincoln) that would have prevented intercourse, and in the 1850s, "many middle-class couples slept in separate bedrooms" as a matter of custom adopted from the english.