L-carnitine supplementation reduces oocyte cytoskeleton damage and embryo apoptosis induced by incubation in peritoneal fluid from patients with endometriosis

Objective: To investigate the protective effect of L-carnitine (LC) against deleterious substances present in the peritoneal fluid (PF) of patients with endometriosis, which may affect the oocyte cytoskeleton and embryogenesis. Design: Experimental study. Setting: Research embryology laboratory at an academic hospital. Patient(s): Frozen metaphase 11 mouse oocytes and embryos. Intervention(s): One hundred metaphase 11 mouse oocytes were divided into five groups and incubated: PF from endometriosis patients; PF from endometriosis patients + LC; PF from tubal ligation patients (patient control); LC only; and human tubal fluid (HTF) alone. A total of 180 eight-cell mouse embryos were divided into: endometriosis only; tubal ligation only; endometriosis + LC; LC alone; and HTF alone. Main Outcome Measure(s): Protective effect of LC on oocytes and embryos. Result(s): Incubation of the oocytes and the embryos with PF from patients with endometriosis statistically significantly damaged the oocyte microtubules and chromosomes and increased embryo apoptosis compared with controls. Incubation with LC (0.6mg/mL) statistically significantly improved microtubule and chromosome structure and decreased the level of embryo apoptosis. Conclusion(s): We propose the use of LC as a supplement in patients with endometriosis, a novel approach that may help improve in vitro fertilization outcome in these patients. (Fertil Steril (R) 2009;91:2079-86. (C)2009 by American Society for Reproductive Medicine.)