When should Progesteron be retested?

The timing for retesting progesterone depends entirely on the clinical purpose. For luteal phase assessment (e.g., infertility, ovulation confirmation), the test is typically performed 7 days after ovulation, which corresponds to day 21 of a 28-day cycle. In irregular cycles, ovulation tracking (e.g., LH kits) is recommended to time the test correctly. For monitoring hormone replacement therapy (HRT), progesterone should be measured at trough level, just before the next dose. During pregnancy, serial progesterone measurements may be used to assess viability or guide supplementation, especially in high-risk pregnancies or after assisted reproduction. The provided context does not contain specific guidance on progesterone retesting. Therefore, this answer is based on general clinical practice and standard guidelines. Note: Interpretation requires knowledge of cycle timing and assay method. Evidence: practice. Sources: none.