During this period, obstetrics and gynecology increasingly framed female reproduction through an endocrine lens, linking ovarian function and hormonal regulation to menstrual and uterine changes. Research patterns combined physiological experiments with clinical observations, while clinicians expanded diagnostic horizons to include conditions such as endometriosis and ectopic gestations, using early cytologic concepts and hormonal insights to inform care. A unifying theme was the shift from purely anatomy-based disease models toward integrated endocrine explanations that guided diagnosis and early therapeutic considerations, including the emergence of the polycystic ovarian syndrome (PCOS) concept.