CA-125 levels are related to the likelihood of pregnancy after in vitro fertilization and embryo transfer

PROBLEM: To assess the relationship between serum cancer antigen (CA)-125 concentrations and the likelihood of pregnancy after in vitro fertilization/embryo transfer (IVF/ET). METHOD OF STUDY: A prospective longitudinal follow-up study was conducted in 44 IVF patients receiving luteinizing hormone-releasing hormone (LHRH) suppression, followed by human menopausal gonadotrophin (hMG). There were no indications of endometriosis. Progesterone or human chorionic gonadotrophin (hCG) were given as luteal support. Serum samples were taken just before oocyte pick-up (OPU), 14 days after ET and, after the establishment of a clinical pregnancy, on day ET + 21. Samples were stored at - 80 degrees C until analysis. CA-125 was measured using a commercially available enzyme immunoassay (IMx CA-125; Abbott, North Chicago, IL, USA). The signed rank (paired samples) and Wilcoxon tests were used for statistical analysis. RESULTS: There were no differences in CA-125 concentrations at the time of OPU between pregnant (n = 18) and non-pregnant (n = 26) IVF patients. After OPU, the CA-125 concentrations rose both in pregnant (P < 0.0001) and in non-pregnant (P < 0.001) patients. This rise was greater after successful implantation, and 14 days after ET, higher CA-125 concentrations were found in the pregnant patients (P < 0.01). CONCLUSIONS: Differences in serum CA-125 concentrations between pregnant and non-pregnant IVF patients appear to be related to the likelihood of successful implantation.