The P+7 draw

The most useful cycle-timed test. Drawn near the mid-luteal peak of progesterone, it gives biochemical evidence that ovulation recently occurred: a value above 3 ng/mL is that evidence.

What it does not do is grade the luteal phase. A single value — or several — does not establish luteal “quality,” and luteal phase deficiency is not established as an independent cause of infertility. Some restorative-reproductive-medicine practices work to a higher target of 15 ng/mL; treat that as one treatment model’s goal, not a general diagnostic threshold.

Because it’s keyed to your ovulation — not a calendar date — timing is everything. Filia schedules it 6–8 days after your detected ovulation, or about 7 days before your expected period when ovulation is unclear.