The withdrawal method refers to pulling the penis out of the vagina and away from the woman’s external genitals before the moment of ejaculation in order to prevent a pregnancy from occurring. However, this method of birth control is not highly effective, as sperm can reside in pre-ejaculation fluid. Also, this method does not prevent against any STIs.
The Wolffian ducts are paired, mesodermal ducts present in the early embryo that will develop into the epididymis, vas deferens, and seminal vesicles in males. In females, they are lost during the early stages of development.