Breast development extension adrenocorticotropic hormone (ACTH)), and thyroid hormones such as thyroxine (and by extension thyroid-stimulating hormone (TSH) and thyrotropin-releasing hormone (TRH)) also play permissive but less well-understood/poorly-characterized roles in breast development during both puberty and pregnancy, and are required for full functional development. Leptin has also been found to be an important factor in mammary gland development, and has been found to promote mammary epithelial cell proliferation. In contrast to the female-associated sex hormones, estrogen and progesterone, the male-associated sex hormones, the androgens, such as testosterone and dihydrotestosterone (DHT), powerfully suppress the action of estrogen in the breasts. At least one
Causes of sexual violence male rapists had less empathy toward women who had been sexually assaulted by an unknown assailant and more hostility toward women than non-sex-offenders and nonoffender males/females. Meta-analyses indicate that convicted rapists demonstrate greater sexual arousal to scenes of sexual coercion involving force than do non-rapists. There is evidence to suggest that sexual violence is also a learned behavior in some adults, particularly as regards child sexual abuse. Studies on sexually abused boys have shown that around one in five continue in later life to molest children themselves. Such experiences may lead to a pattern of behavior where the man regularly