Basal values of serum FSH levels

The basal values of the follicle-stimulating hormone (FSH) are easy to assess and are a good prognostic marker for the possibilities to achieve pregnancy by natural and stimulated cycles. Serum FSH levels, which are higher than 12 mIU/ml, are connected with poor ovarian response to stimulation.

Basal values of serum inhibin B levels

Inhibin В is a hormone secreted by the granulose cells of the so-called antral follicles in the ovary (follicles with dimensions from 50 microns to 2 mm). The decrease of serum inhibin В levels is connected with advanced reproductive age of women. Inhibin B also participates in the pathophysiology of polycystic ovarian syndrome (PCOS). Inhibin В is also a marker for diagnosing of some ovarian carcinomas.
The reference values of inhibin B for the Bulgarian population are assessed between 33 pg/ml and 190 pg/ml.

Basal values of serum Anti-Mullerian hormone levels

Anti-Mullerian hormone (AMH) is produced by the granulosa cells of preantral and small antral follicles and its levels can be assessed in serum. Since the number of ovarian follicles declines with increasing age, AMH levels might be used as a marker for ovarian ageing. The reference values of AMH for the Bulgarian population are assessed between 0.9 ng/ml and 1.7 ng/ml (1,46 ±0,93 ng/ml ).

Clomiphene citrate challenge test (СССТ)

This test is based on the possibility to restore the reproductive system by applying clomiphene citrate (CC). FSH levels lower than 10 IU/ml are regarded as normal; 10?12 IU/ml are borderline values; levels exceeding 12 IU/ml are abnormal.

GnRH agonist stimulating test (GAST)

This test assesses the changes in estradiol (Е2) on day 3 after applying GnRH agonist on day 2 of the menstrual cycle. The result from the test depends on the pituitary production of gonadotropins and on the ovarian response to stimulation.

Exogenous follicle stimulating hormone ovarian reserve test (EFORT)

This test is based on the application of gonadotropins and on estradiol dynamics (Е2) as a function of the ovarian response. Women whose Е2 levels are increased by more than 30 pg/ml have adequate ovarian response compared to women whose Е2 levels are lower than 30 pg/ml.

Ultrasound tests

• Ultrasound antral follicle count (AFC) provides objective information on the ovarian reserve. The test is performed during the early follicular phase (2-4th day) and the number of the 2-10 mm follicles in both ovaries is counted. With mean number of antral follicles of less than five, the ovarian reserves are considerably reduced.


• Measurement of the mean ovarian diameter (MOD). It is performed during the early follicular phase (2-4th day). With MOD values of less than 20,6 mm, there is a significant likelihood for reduced ovarian reserves.