Understanding Problematic Bleeding When Using Contraception: Guidance for Clinicians.

Abnormal uterine bleeding (AUB) is a common side effect of hormonal contraceptive (HC) use and represents a significant cause of treatment discontinuation. Two main types of bleeding are recognized: withdrawal bleeding, which occurs during the hormone-free interval following a sudden drop in hormone levels, and breakthrough bleeding (BTB), defined as unscheduled bleeding during active hormone administration. Combined oral contraceptives (COCs) may induce BTB due to hormonal fluctuations or insufficient endometrial stabilization, while progestin-only contraception (POC) is commonly associated with abnormal bleeding due to endometrial changes induced by continuous progestin exposure. A structured and clinically oriented framework for the management of AUB in the context of HC is presented, highlighting the importance of appropriate counseling. Some strategies to improve adherence have been proposed, recognizing non-compliance as a major contributor to unscheduled bleeding. Contraceptive choice is addressed as an individualized process, involving adjustments to hormone type and dosage based on woman-specific needs. The aim is to provide clinicians with a clear and structured tool to address a highly prevalent yet often overlooked issue, still marked by significant uncertainty and inconsistency in the current literature.