When do the external genitals of a fetus become recognizable?

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During the first eight weeks of development, there is no external indication of a fetus's sex, as the external genitalia remain in a neutral or indifferent stage. During this period, both sexes possess similar external genitalia represented by three simple protuberances: a genital tubercle, a pair of urogenital folds, and a pair of genital swellings.12

These rudiments begin to assume recognizable male or female characteristics at approximately three months of gestation. In males, the tubercle and urogenital folds combine to form the penis, while the genital swellings fuse to become the scrotum. In females, the tubercle remains small to become the clitoris, and the urogenital folds and genital swellings remain unclosed to form the lesser and greater lips of the vulva, respectively.21