A woman’s age is a key factor in fertility. The number of ‘created’ egg cells is highest in the female unborn child, at six to seven million, and by the time the baby is due this number has already decreased to around one million. This shows us that in some areas the body begins to deteriorate from birth.
At the beginning of puberty, the follicle pool in young girls ‘only’ consists of around 300,000 egg cells. Egg degradation accelerates significantly from the age of 35. After the ovarian reserve is exhausted, the woman still has regular ovulatory cycles with largely unusable eggs. The age-related decline affects both the number of eggs and the quality of eggs. The rate of chromosomal abnormalities increases significantly with maternal age above 38.
While the clinical pregnancy rate is high in women up to the age of 37, it drops significantly from the age of 38. In a 40-year-old woman, the pregnancy rate is 25 per cent per embryo transfer, a 44-year-old woman has a probability of 5 to 10 per cent.
AMH (Anti-Mullerian Hormone) is now used to asses ovarian activity and reserves. In adult women, the AMH value decreases with age, parallel to the breakdown of the pool of follicles. From the age of 40 the AMH level drops rapidly, five years before the last menstrual period, the value is practically no longer detectable – despite regular cycles. AMH can be determined independently of the cycle.
However, AMH is in itself not the only decisive factor in fertility treatment. Pregnancies have been achieved in isolated cases in patients with AMH of 0.0.