The use of many drugs can result in some degree of hair loss. This includes the use of oral anovulatory drugs, commonly known as birth control pills. The hair loss that occurs is similar to that seen in post-partum cases of alopecia. It manifests as a slight shedding of the hair due to a disturbance in the woman’s hair cycles and is usually minor and temporary.
Similarly, it has also been noted that androgen-dominant (androgens are male hormones like testosterone) contraceptives have caused hair loss in women who were genetically predisposed to androgenic alopecia (also known as female pattern baldness). Cases such as these are usually easily taken care of by switching to an estrogen-dominant contraceptive, as androgens are known to be associated with genetic hair loss in both men and women.
Before taking any drug, you should always discuss the possible short-term and long-term side effects with a medical professional, and weigh the risks and advantages yourself.