Investigation of human embryo implantation requires a non-disruptive means of studying the endometrium during the window of implantation. This study describes a novel approach of cytokine profiling in endometrial secretions. Endometrial secretions aspirated prior to embryo transfer from 210 women undergoing IVF or intracytoplasmic sperm injection were analysed by a multiplex immunoassay. Ten mediators [interleukin (IL)-1beta, IL-6, IL-12, IL-18, tumour necrosis factor-alpha, macrophage migration inhibitory factor, eotaxin, monocyte chemotactic protein-1, interferon-gamma inducible protein-10, vascular endothelial growth factor] were detectable in 90-100% of the samples. Heparin-binding epidermal growth factor, IL-5, IL-17, IL-10, Dickkopf homologue-1 and IL-15 were detected in 23-76%, whereas interferon-gamma was not detectable in any of the samples. To assess possible contamination of samples, cervical mucus was also aspirated for comparative analysis in 22 women. The endometrial cytokine profile differed significantly from cervical mucus. Pregnancy rates of the study participants who underwent endometrial secretion aspiration were compared with 210 controls matched for important prognostic variables; no significant differences were found. In conclusion, cytokine profiling in endometrial secretion offers an objective, non-disruptive means of analysing the in-vivo milieu encountered by the embryo and offers a new and potentially valuable approach to studying the endometrial factor in human embryo implantation.

Applying the ICSI procedure prevents colonization of the culture dishes by micro-organisms. Infections in IVF culture dishes are mainly caused by bacterial strains insensitive to the antibiotics used or due to yeast colonization by Candida species which frequently reside in the vagina.

Background: Mammalian oocytes acquire competence to be fertilized during meiotic maturation. The protein kinase CDC2 plays a pivotal role in several key maturation events, in part through controlled changes in CDC2 localization. Although CDC2 is involved in initiation of maturation, a detailed analysis of CDC2 localization at the onset of maturation is lacking. In this study, the subcellular distribution of CDC2 and its regulatory proteins cyclin B and SPDY in combination with several organelle markers at the onset of pig oocyte maturation has been investigated.