Gender is a term used in linguistics which is incorrectly applied to biology. If you use the word “gender” in the context of human biology you’ve lost the argument right out of the gate. Sex, and only sex is the term that applies to men and women. Gender is a word weapon that’s been inserted into the minds and mouths of us and it should be rejected out of hand.
First time I saw the word gender, I immediately thought of Jr high French, which used gender as an indicator of whether one should use le or la. John Money, pedophile plastic surgeon, popularized using gender in place of sex.