Adult male offspring from MIA mothers display reduced USV responses in a social encounter with a female. During interactions with a female in estrous phase, MIA males emit fewer vocalizations (A) and also produce significantly fewer two step frequency and chevron syllables (B) than controls. Significant differences are indicated by *p < 0.05, **p < 0.01 and ***p < 0.005. USV classification: 1F, one frequency step; 2F, two frequency step; 3F, three and more frequency step; HM, harmonic; CV, chevron; CX, complex; FT, flat; UP, upward; DN, downward; ST, short.