When in your cycle to test which hormone
Enter your cycle length and the first day of your last period. You'll get the right draw days for an early-follicular baseline (FSH, LH, estradiol) and a mid-luteal progesterone — plus what to do if you're on hormonal contraception.
How to read this
- · The luteal phase (ovulation → next period) is reliably ~14 days. The follicular phase is the variable bit, so ovulation day shifts with cycle length.
- · For a 28-day cycle: ovulation around day 14, progesterone day 21. For a 32-day cycle: ovulation around day 18, progesterone day 25.
- · Irregular cycles: progesterone timing matters most. Either track ovulation directly (LH strips or basal body temperature) or do two draws across the suspected luteal window.
- · On combined hormonal contraception: skip the cycle-dependent markers; the rest of a panel (AMH partially suppressed, thyroid, androgens, metabolic, micronutrients) still gives useful information.
Let us schedule the right day for you
Book a Her Form panel and our team confirms your cycle phase before the at-home draw. Written specialist review by our health specialists. Robyn is available for an optional 1:1 results consult.
Why does cycle day matter for hormone testing?+
Estradiol, progesterone, FSH and LH change dramatically across the cycle. A 'normal' progesterone on day 7 is meaningless; on day 21 of a 28-day cycle it confirms ovulation. Testing the right marker on the right day is half the value of the panel.
What day is best for FSH, LH and estradiol?+
Day 2, 3 or 4 of your cycle — the early follicular window. This is when FSH and LH are at their baseline and estradiol is low. It's the standard timing for ovarian-reserve and pituitary assessment.
When should I test progesterone?+
Around 7 days after ovulation (mid-luteal). For a textbook 28-day cycle that's day 21. For a 30-day cycle it's day 23; for a 26-day cycle, day 19. Our tool calculates the right day for your cycle length.
What if my cycle is irregular?+
Then a single-day progesterone is unreliable. Options: track ovulation (LH strips or BBT) and test 7 days after, or do a 'series' of progesterone draws across the suspected luteal phase. Testosterone, AMH, thyroid, prolactin and SHBG don't require cycle timing.
What if I'm on hormonal contraception?+
Combined pills, patch and ring suppress your own FSH, LH, estradiol and progesterone — they will read suppressed regardless of cycle day. AMH is suppressed ~20–30%. Thyroid, ferritin, vitamin D, prolactin and androgens are still meaningful.
Does Her Form help me schedule the right day?+
Yes. When you book, our team confirms your cycle phase and books the at-home draw for the right window. Written specialist review by our health specialists. Robyn is available for an optional 1:1 results consult.