Which STRAW stage is characterized by variable cycle length and increased FSH?

Which STRAW stage is characterized by variable cycle length and increased FSH?

• A. STRAW -3
• B. STRAW -2
• C. STRAW -1
• D. STRAW 0

Answer: (C)

Variable cycle length with rising FSH signals the onset of the menopausal transition. In this early perimenopause stage, the ovarian follicle pool declines, so estrogen and inhibin B feedback on the pituitary weakens. The pituitary responds by increasing FSH, while ovulation becomes less predictable. As a result, menstrual cycles become irregular in timing and length. This combination—newly elevated FSH with variable cycle length—best fits the early menopausal transition stage in STRAW. Later stages show more pronounced irregularity and eventually cessation of menses, while earlier stages tend to have regular cycles with stable hormonal feedback.

Variable cycle length with rising FSH signals the onset of the menopausal transition. In this early perimenopause stage, the ovarian follicle pool declines, so estrogen and inhibin B feedback on the pituitary weakens. The pituitary responds by increasing FSH, while ovulation becomes less predictable. As a result, menstrual cycles become irregular in timing and length. This combination—newly elevated FSH with variable cycle length—best fits the early menopausal transition stage in STRAW. Later stages show more pronounced irregularity and eventually cessation of menses, while earlier stages tend to have regular cycles with stable hormonal feedback.