prenatal stress does have an effect on brain sexual differentiation after measuring the volume of the sexually dimorphic nucleus of the preoptic area of both female and males in the control and stressed groups. prenatal stress inhibits the masculinization of the male brain by inhibiting the growth of the sexually dimorphic nucleus of the preoptic area. previous studies found that a decrease in testosterone is seen in pups of prenatally stressed mothers. authors suggest this may cause the reduced in the sexually dimorphic nucleus of the preoptic area and says it is similar to the effects of neonatal castration. also, stressed males had larger sexually dimorphic nucleus of the preoptic area at birth, but then at 20 and 60 days are found to only have 50% of the volume of the control males. whereas control males are two times larger than control females on days 20 and 60, but the stressed males show no statistical difference to control females on respective days. these findings show support that the male brain is not showing the expected sexual dimorphism when prenatally stressed.