Understanding AMH Level: Too Low or Too High?

At Sunfert, we believe understanding ovarian reserve is a key step for a woman in planning her fertility journey.

The Anti-Mullerian Hormone (AMH) test is the most reliable assessment to assess ovarian reserve and is often the first test encouraged by many experienced fertility specialists.

• It is a single blood test and can be done anytime during the menstrual cycle.
• It estimates how the ovaries may respond to stimulation during an IVF cycle.
• It may help identify women at risk of early menopause and earlier fertility decline.

AMH is produced by granulosa cells of early developing ovarian follicles. It is closely linked to your age and antral follicle count (AFC) in your ovaries, helping show how many eggs you might have left. While high AMH may indicate a higher egg quantity, it does not guarantee pregnancy. Likewise, low AMH does not necessarily mean infertility.

Notes:

• Granulosa Cells: Helper cells in the ovary that surround and nurture a developing egg, providing nutrients and signals for its growth. They also produce estrogen and assist in ovulation, making them essential for fertility.
• Antral Follicle Count (AFC): Is the number of small, early-stage eggs visible in the ovaries on an ultrasound.

AMH testing is especially important today as more women in Malaysia are delaying childbearing into their 30s and 40s. 

Tracking AMH levels helps women to:

• understand their reproductive health
• plan their parenthood timeline
• consider options like egg freezing, if needed

In recent years, several charts have been developed showing normal AMH levels from birth to menopause:

• Before puberty: AMH is low
• Early puberty: AMH rises
• Ages 20 to 25: AMH peaks
• After 25: AMH gradually declines and is usually undetectable by menopause

The reason AMH rises during early puberty is still unknown.

Practical tip: AMH is most useful for assessing ovarian ageing in women over 25.

When AMH exceeds 48 pmol/L, it may indicate Polycystic Ovarian Syndrome (PCOS).

• PCOS is the most common hormonal disorder in women of reproductive age and a frequent cause of subfertility.
• Hormonal imbalances in PCOS prevent the regular development of a dominant follicle, leading to irregular or infrequent ovulation.
• As a result, many immature eggs remain in the ovaries.

These eggs, within their follicles, produce AMH, which explains why women with PCOS often have elevated AMH levels.

Low AMH indicates lower number of eggs (follicles), often termed low ovarian reserve. 

It is important to read AMH in the context of many factors, most importantly your age. 

Women are said to have diminished ovarian reserve (DOR), when the number of eggs is much lower than expected for women the same age. 

When this happens, your doctor might get you to perform some genetic screening such as Fragile X Syndrome. 

Other causes of DOR are:

• Smoking
• Endometriosis
• Ovarian Surgery
• Cancer Treatment
• Autoimmune Diseases
• Pelvic Inflammatory Disease (PID)

In many cases, no apparent cause can be identified.

If a woman experiences menopause before the age of 40, they have Premature Ovarian Insufficiency (POI), which impacts 1 in 100 women. 

Women with POI can experience symptoms such as irregular periods, typically shortening of menstrual cycles well into their 30s.