Which of the following is a possible side effect of forgetting to take oral contraceptive pills?

Forgetting to take oral contraceptive pills can significantly decrease their effectiveness in preventing pregnancy. Oral contraceptives work primarily by inhibiting ovulation, and when doses are missed, ovulation may occur, leading to the possibility of an unintentional pregnancy. This is especially true if the pills are missed during the first week of the cycle or if multiple doses are omitted. While increased menstrual flow, ovarian cyst formation, and menstrual cramping can be associated with hormonal fluctuations or adjustments, they are not the primary concern when oral contraceptives are not taken as prescribed. The primary risk linked to missed doses is the potential for ovulation and subsequent pregnancy, making unintentional pregnancy the most pertinent consequence of forgetting to take the pills.