Grant: Project Grant

Infertility affects around 15% of couples of reproductive age, and about half of the infertility is associated with male partner. To date, intracytoplasmic sperm injection (ICSI) is a common clinical practice as an assisted reproductive technology (ART) procedure to achieve fertilization in vitro. Despite the relatively high fertilization rate of ICSI, the latter is a more expensive and invasive treatment compared to the standard in vitro fertilization (IVF) and the intrauterine insemination (IUI) procedures. There has been increasing reports on the association of increased genetic anomalies and birth defects in ICSI concepti. This may be due partly to damages to gamete chromosomes caused by the invasive ICSI procedure. To encourage the use of the less invasive standard IVF and IUI for male infertility treatment, there is need to improve the fertilization rate of standard IVF and IUI. One possible approach is to treat sperm with oviductin, a secreted oviductal glycoprotein which has been shown to enhance sperm functions and fertilization. In subfertile men, sperm motility is highly correlated with fertilizing ability. It is generally recognized that sperm with severe motility aberrations are incapable of fertilization without extensive ART interventions. Despite its clinical importance, little is known about the molecular mechanisms that regulate human sperm motility. Underlying the present investigation are two fundamental questions that need to be addressed before oviductin can be applied to standard IVF and IUI in fertility centers. Functionally, does oviductin enhance sperm fertilizing ability and what is the mechanism that regulates the functional property of oviductin? Clinically, will supplementation of culture medium with oviductin enhance fertilization as measured by in vitro functional assays? The ultimate goal is to improve the health service use of IVF and IUI procedures involving couples with male infertility indications in Canada and worldwide.