Secondary amenorrhea is defined as the absence of menses for 3 cycles or irregular menses for 6 months after having regular cycles.

• A. Absence of menses for 3 cycles or irregular menses for 6 months after having regular cycles.
• B. Absence of menses for 12 consecutive months.
• C. Absence of menses before menarche.
• D. Absence of menses for more than 2 years after puberty.

Answer: (A)

Secondary amenorrhea means a person who has had menses in the past stops having them for a defined period. The defining threshold is reached relatively quickly after puberty, indicating a new interruption in normal cycles. The best choice states that menses are absent for three consecutive cycles or for six months if the cycles have been irregular after regular cycles. This matches the standard criterion used clinically: if cycles were regular, three missed cycles signal secondary amenorrhea; if cycles are irregular, six months of absence/irregularity after prior regular cycles counts as secondary amenorrhea as well.

Other options don’t fit the standard definition: waiting 12 consecutive months to label secondary amenorrhea is a longer threshold than the usual criterion; absence before menarche describes primary amenorrhea; and remaining absent for more than two years after puberty isn’t the diagnostic threshold used for secondary amenorrhea, though prolonged absence would still be concerning.