AMH (anti-Müllerian hormone) is the best test available for assessing ovarian reserve: it directly reflects the number of follicles left in the ovaries, and it can be drawn on any day of the cycle. A value below 1.0 ng/mL points to diminished reserve, while a high AMH, above 4.5, can point to PCOS.
| Result | AMH (ng/mL) |
|---|---|
| Ideal value, under 30 | 1.5 to 4.0 |
| Ideal value, 30 to 40 | 1.0 to 3.0 |
| Diminished reserve | below 1.0 |
| Severely reduced reserve | below 0.5 |
| High: can point to PCOS | above 4.5 |
Values as given in Chapter 32.
The ideal range depends on age: the same value can be below the ideal range under 30 and within it from 30 to 40. And a high value is not a “better” result: above 4.5, AMH can point to PCOS.
Because it doesn't depend on the day of the cycle, AMH is easy to include early. In the book's typical workup sequence, it goes in month 1, alongside the 11 preconception tests and the semen analysis.
The book pairs AMH with two other markers of ovarian reserve. Together with the antral follicle count, it is one of the two best markers available.
A transvaginal ultrasound between day 2 and day 5 of the cycle, counting the small follicles (2 to 10 mm) in each ovary. It is a visual marker of reserve.
| AFC result | Total follicles |
|---|---|
| Normal | 8 to 25 |
| Reduced | below 7 |
| High (PCOS suspected) | above 25 |
Drawn between day 2 and day 4 of the cycle. FSH that is elevated this early is a sign of reduced ovarian reserve: the body has to “shout” louder to get a response.
AMH measures reserve: how many eggs remain. That is one of the three things the book says change with age. The other two, egg quality (how many have normal chromosomes) and hormonal response (how your cycle behaves), are not what this number shows.
What it does give you is information about you, instead of an average for your age. If the markers point to low reserve (low AMH, reduced AFC and/or elevated baseline FSH), that is the picture of diminished ovarian reserve, which the book covers among the most common diagnoses.
AMH is in Chapter 32 of Map to the Positive, in Station IV, Signs, together with the rest of the advanced workup: the HSG for the tubes, the in-depth hormone panel and the genetic tests reserved for specific cases. The chapters that follow connect each result to a diagnosis and to the treatments available, from the simplest to IVF.
Take 30 days. If it does not give you more clarity than everything you have read for free so far, ask for a refund and you get every cent back. We cannot promise you a pregnancy. We can promise you will not be guessing.
References: ASRM Practice Committee. Testing and interpreting measures of ovarian reserve, 2020.