We speak of Infertility of Unknown Origin (DOE) when after the basic study of infertility there is no cause that justifies reproductive failure. The basic infertility study does not attempt to analyse each of the events or organs that determine fertility. It is not a question of identifying what does not work in a person, but of establishing whether the minimum conditions are in place to be able to start a couple's reproduction treatment. In other words, it is a question of establishing a therapeutic strategy. The basic studies are therefore aimed at determining whether there is:
- Adequate ovarian reserve in the woman
- Affectation of seminal quality in men
- Tubal alteration
- Uterine factor
When this study is normal and the woman is less than 38 years old, it is advisable to start with insemination treatments. For women over 38, we assume that the oocyte quality will not be optimal and it is proposed to start with In Vitro Fertilization (IVF) because this technique is more effective in these age ranges. In the case of failure of the insemination cycles (3- 4 cycles), the young couple will choose to carry out IVF cycles. It is not uncommon for responses to the cause of this unexplained infertility to appear during the IVF cycle: insufficient response to stimulation, poor oocyte quality, failure to implant the embryos... Therefore, the diagnosis of unknown infertility is framed within the context of the strategy of approaching the couple with reproductive dysfunction.
It is estimated that up to 15-20% of couples consulting for infertility fall into the ideopathic sterility category. It is important to point out that the advanced age of the woman is in itself a factor that may justify the difficulty in achieving gestation. To speak of idepathic sterility in a woman over 38 years of age would not be correct, since in these cases, we are already heading towards IVF due to the qualitative affectation of the oocytes and the risk of affectation of the ovarian reserve. This is something that is often difficult to assume, when all the studies are normal and the expected success with the reproduction techniques is not achieved. Often the techniques themselves will give us answers by allowing us to dynamically evaluate ovarian function and the quality of embryos and gametes. It is possible, on the other hand, that if more complex studies are carried out: genetic studies, advanced sperm quality tests, immunology studies... more factors are discovered that hinder the fertility of the woman. However, it is not indicated, from the outset, to carry out all these tests since the probabilities of success with assisted reproduction techniques are good.