My friend's daughter has autism and she was getting her dressed and noticed half her breast felt hard when putting her bra on. she checked the other breast and it was the same. her daughter has never had a period and she's 20. should she be worried?

Since both breasts are hard, hormonal influences are to blame. Has she had a gynecological examination to ensure that there are no genital causes of amenorrhea,polycystic ovaries,pituitary issues etc? Start with the gynecologist. Appropriate testing will be done.

Any young woman with no menses by age 15 should be evaluated. There are genetic reasons this may be amiss and could tie into the autism. There are also rare cases where the parts are not all present which also has genetic implications.