What are the best dates of the cycle for a blood draw?
Our blood science algorithm reports on optimal status, with accuracy best achieved during a mid-luteal phase of the menstrual cycle. At this stage we would typically expect to see the peak of Progesterone and rises in Oestrogen. The mid-Luteal phase is days 21-23 of a 28 day cycle. You will need to calculate accordingly if your client’s cycles are shorter or longer.
What if my client’s cycle is erratic?
If your client has been tracking their cycle for some time you can use this data as a best estimate of their mid-luteal phase.
If their periods have begun to change in the last few menstrual cycles, we suggest going by their typical pattern to estimate the mid-luteal phase.
I have calculated my client’s mid-luteal phase and this falls on a Friday or over the weekend. Which day is best for blood draw?
If your clients’ blood draw date falls on a Friday, you can use a next day special delivery to return to the lab on a Saturday morning. However, this is not always guaranteed. If the return sample does not get to the lab, you will need to pay for a new blood test kit and a redo of the blood draw. FunctionalDX are not responsible for Royal Mail or courier returns to the lab.
It would be day 26/27 before my client can take the test. How important is it that she does test on day 21?
For optimal female hormone testing we do advise that a blood test taken during the mid-luteal phase is best due to the peaking of progesterone and rises in oestrogen, and this activity should be reflected within the results. We would suggest that you wait until the next cycle to take the bloods.
If your clients’ blood draw would be best on a Saturday and Sunday?
Review their cycle length and decide if a Friday draw with next day special delivery would be best, or a Monday blood draw. Aiming for a blood draw on day 21-23, means one day should fall on a weekday. We will support you when reviewing the test results if the blood draw date hasn’t been the ideal date.
What are the best dates of the cycle for a blood draw when a client is taking contraception?
Our blood science algorithm reports on optimal status, with accuracy best achieved during a mid-luteal phase of the menstrual cycle. At this stage we would typically expect to see the peak of Progesterone and rises in Oestrogen. The mid-Luteal phase is days 21-23 of a 28 day cycle. You will need to calculate accordingly if your client’s cycles are shorter or longer.
When a client is on contraception you can test on any day of the cycle but take into account that the algorithm will calculate for an optimal mid-luteal phase. A contraceptive period is not the same as a regular period, and there for you will need to take this into account when interpreting the result.
Fertility testing
For fertility, please undertake the test on day 3.
If you purchase an FDX Femme Fertility test, you will also be sent a finger prick test for day 21 progesterone levels. Again, please calculate the days in line with your clients cycle.
My client is peri-menopausal, when should they take the test?
We recommend calculating for a mid-luteal draw, days 21-23 of a 28 day cycle and calculate accordingly, even if their cycles have started to change or become more erratic.
My client is post menopausal, when should they test?
Post menopausal women can take an FDX test on any day.
We also have two useful blogs on testing female hormones.