absent
Throughout nature the longer-living creature is, barring accidents, always the female because she bears and nurtures the next generation. Every species does this. It is why peahens, for example, look dull, drab and can easily conceal themselves from predators but peacocks are colourful to attract mates.
I think I read some serious article quite a while ago about how the "default" for a foetus is always female. Think about inherited diseases or problems that affect only those with Y chromosomes.
It is no surprise to me that medical science still regards male as the "norm". This has less to do with science and everything to do with so many centuries of the way women were regarded. It takes a very long time to undermine preconceptions
Sorry, but "we all start out female in the womb" is a myth. 99.999% of humans have either XX or XY chromosomes at conception and develop accordingly - the embryo's repoductive system can become visible as early as 8 weeks.