An understanding of the complexities of all levels of biological variation is necessary for efficient health care delivery. Some of the major textbooks teach anatomy as a male-female binary. Anatomical sciences curricula need to adopt a more current approach to sex.
Developments in biology and genetics in recent decades have caused significant shifts in the understanding and conceptualization of human biological variation. Humans vary biologically in different ways, including individually, due to age, ancestry, and sex. An understanding of the complexities of all levels of biological variation is necessary for efficient health care delivery. Important steps in teaching medical students about human variation could be carried out in anatomy classes, and thus, it is important that anatomical education absorbs new developments in how biological variation is comprehended. Since the early 1990s biological sex in humans has been vigorously investigated by scientists, social scientists, and interest groups. Consequently, the binary division in male and female sex has been called into question and a more fluid understanding of sex has been proposed. Some of the major textbooks teach anatomy, particularly of the urogenital system, as a male-female binary. Anatomical sciences curricula need to adopt a more current approach to sex including the introduction of the category of "intersex"/"differences in sexual development" and present sex as a continuum rather than two sharply divided sets of characteristics. This approach offers a better understanding of the complexity of sex differences and, at the same time, provides students with an improved theoretical framework for understanding human variation in general, transcending the limitations of biological typology. When well delivered, the non-binary approach could play a significant contribution to the formation of competent and responsible medical practitioners and avoidance of problematic practices such as non-consensual "normalizing" surgeries.