All bones in the adult skeleton can help to determine whether the individual was male or female.  However, there are two areas of the skeleton that are more reliable and these are the pelvis and the skull.

During puberty, the growing pelvis responds to circulating sex hormones – testosterone (male) or oestrogen (female) and the bones grow differently.  In particular, the female pelvis changes shape in response to circulating oestrogen, so that in the future it will be large enough to accommodate the passage of a fetal skull during birth.

The skull responds more to testosterone to accommodate large sites of muscle attachment and, as a result, the male skull is more robust than the female with stronger sites of muscle attachment.