Endometriosis and infertility: a multi-cytokine imbalance versus ovulation, fertilization and early embryo development.

Endometriosis is tightly linked to infertility which is manifested at very early or more advanced stages of the gestational cycle. Alteration on the production of a great number of cytokines/growth factors can be accused for problems on ovum maturation, fertilization or implantation. Yet, macroscopically these stages are characterized by the inability of conception. A closer look of the cytokinic profile during the conceptional and early gestational cycle could, however, localize the problem and allow a therapeutic approach. In this commentary, going through the cytokine requirement during ovulation, fertilization and the early stages of pregnancy, it became possible to specifically define the harmful endometriosis-induced cytokines for each of the conceptional and early gestational stages. Thus, regulating the levels of interferon-gamma and tumor necrosis-alpha will facilitate ovulation and fertilization, whereas adjusting the levels of interleukin-1beta and colony stimulating gactor-1 will facilitate implantation.