Progesterone-day 21 1 health indicators in store/ home

The Progesterone (Day 21) Test is a single-marker blood test measuring progesterone in the second half of the menstrual cycle to confirm whether ovulation has occurred, processed by London Medical Laboratory (LML), a UKAS-accredited ISO 15189 laboratory, and sold by Ways Pharmacy (UK).

Key facts

Who it is for

• Women trying to conceive who want to confirm whether they are ovulating
• Women with irregular cycles investigating possible ovulation problems
• Women being assessed for polycystic ovary syndrome (PCOS) as part of a wider work-up
• Women who want an objective progesterone reading to discuss with a fertility clinician or GP

Not suitable for: use as a complete fertility assessment on its own; acutely unwell people who need urgent assessment; replacement for advice from a fertility specialist or GP.

What is measured

• Progesterone — the hormone that rises sharply in the second half of the cycle after ovulation. A raised mid-luteal level supports that ovulation has occurred; the reference range and your clinical context guide interpretation.

How it works

1. Complete payment online and choose your option: an appointment at Holborn London, or an at-home self-collection kit posted to you.
2. Time your sample correctly: about 21 days after the first day of your last period if your cycle is regular, or about 7 days before your next period is due if your cycle is irregular.
3. For in-store, attend Ways Pharmacy, 77 Southampton Row, London WC1B 4ET, where a trained operator takes a blood sample. For at-home, follow the kit instructions to collect a finger-prick sample and return it in the prepaid packaging.
4. Your sample is sent to London Medical Laboratory for analysis.
5. You receive a written report with your result against the reference range, typically within 3–5 working days. A pharmacist can talk you through it and recommend GP or clinic follow-up where appropriate.

Frequently asked questions

When in my cycle should I take a progesterone test?

For ovulation confirmation, take the sample about day 21 of a regular 28-day cycle (counting the first day of bleeding as day 1). If your cycle is irregular or longer, take it about 7 days before your next period is due. Timing matters because progesterone only rises after ovulation.

How does this test confirm ovulation?

Progesterone rises in the second half of the cycle once an egg has been released. A raised mid-luteal progesterone level supports that ovulation has occurred. Your report shows your result against the reference range; a pharmacist or clinician interprets it alongside your cycle pattern.

How long do results take?

Results are typically returned 3 to 5 working days after London Medical Laboratory receives your sample. You will receive a written report showing your level against the reference range.

Is the laboratory accredited?

Yes. Samples are processed by London Medical Laboratory (LML), a UKAS-accredited laboratory operating to ISO 15189, the international standard for medical testing laboratories.

What if my result is unexpected?

A single progesterone reading does not diagnose a fertility problem on its own. The pharmacist will explain what your level means and, where appropriate, recommend follow-up with your GP or a fertility clinic. Reference ranges are provided with your report.

When to seek further advice

This test does not diagnose a fertility condition. Reference ranges are provided with your report; discuss your results with a clinician, and if a result is abnormal or you have ongoing fertility concerns, follow up with your GP or a fertility clinic.

This is a private health screening service. Results are interpretive and do not replace clinical diagnosis by a GP or specialist. Abnormal results should be followed up with your GP.