Patterns of ASD risk to children born after the multiplex criterion are met. After a family has two affected children, ASD recurrence risk is less for later-born males, particularly those in male-only (MO) families. Line graphs show the proportion of affected children born first and second after a second affected child in all families with at least one subsequent birth by (A) sex, (B) family type as female-containing (FC) or MO, and (C) by sex within each family type. Line plots corresponding to each group are indicated by colors (blue for males, red for females) and solid (female-containing (FC) families) and dashed (male-only (MO) families) lines. The number of families evaluated in each group, the relative risk (RR) to the child born first versus second after the second affected child, and the P value from a two-sided Fisher’s exact test are shown in the tables below each panel. Whiskers note the 95% confidence intervals around each recurrence rate estimate.