biological sex

noun2

1. •
   sex, as in the biological factors that cause an individual member of a species that uses sexual reproduction to produce either male gametes (sperm or spermatozoa) or female gametes (ova).

   • Biological sex [is] constituted by sex characteristics (chromosomes, gonads, internal genitalia, external genitalia, hormones and secondary sexual manifestations). — 1984
2. •
   Synonym of birth sex (“sex assigned to a person when born”).