There's this meme going around that some people are trying to use against Creationism. It says, "All humans begin as female. The Y chromosome -- which is only present in males -- is not activated in the first 5-6 weeks of embryonic development." Anyway, they're trying to say that Adam couldn't have been the first human, if this is true. I would never not believe what the Bible says, but I don't know what to say against people who are using this to speak ill of the Bible.
"Nevertheless, neither is man independent of woman, nor woman independent of man, in the Lord. For as woman came from man, even so man also comes through woman; but all things are from God" (I Corinthians 11:11-12).
There is an implied assumption that Adam was born. The claim is that there are no males during the first five weeks of development, so the first human could not be a male. The falsehood is exposed when you realize that Adam was made an adult human. "And the LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living being" (Genesis 2:7). There was no conception, development, or birth. In the first day, he was conversing with God, receiving commands from God (Genesis 2:16-17). Adam also named the animals the first day of his life (Genesis 2:19). Adam did not even start life as an infant.
Even the foundation of the argument is false. Sexual organs do not appear until the fifth week of development. This makes logical sense, it takes time for a single cell to divide and specialize before distinct features can come into play. The fact that the sexual organs don't form until the fifth week does not imply that the genes on the Y-chromosome just activated. Why isn't being argued that the X-chromosome also doesn't activate until the fifth week?
To illustrate what is going on, consider a college student looking at his schedule of course. His first few semesters are typically filled with generalized courses that apply to any area of specialization. The courses taken by a future lawyer may not look all that different from a future English teacher. But as the student gets deeper into his studies, his courses become more specialized to his goal.
When a child starts out as a single cell, it is hard for external observers to determine which way the cell will specialize. It isn't until the fifth week that enough changes have accumulated so that the direction of specialization can be observed. Prior to that point both males and females develop in basically the same order, but it is false to conclude that there are no differences since the changes are driven by the blueprint in the child's DNA, which are different.