Gigantomastia following the use of a subdermal contraceptive: a case report

Objective: To describe a case of secondary gigantomastia following the use of a subdermal contraceptive implant, as well as to evaluate the probable causality of the implant as the cause of this condition. Materials and methods: We present the case of a 23-year-old nulligravid patient who, one month after the insertion of a subdermal contraceptive implant, began to experience rapid breast enlargement, mastalgia, localized pruritus, back pain, and an anxiety disorder. Complementary studies ruled out a hormonal, oncological, or pregnancy-related etiology. Two months after the insertion of the subdermal implant, it was removed; however, breast gland enlargement continued after its removal. Reduction mammoplasty was required for definitive treatment. The Naranjo algorithm was applied to determine the likelihood of a causal relationship. Conclusions: To the best of the authors' knowledge, the probable association between gigantomastia and the use of subdermal contraceptives has not been previously described in the literature. It is important to monitor patients with progesterone implants for the development of gigantomastia.