Kathleen Lin

Extracellular Adenosine 5′-Triphosphate Alters Motility and Improves the Fertilizing Capability of Mouse Sperm

Abstract Extracellular adenosine 5′-triphosphate (ATPe) treatment of human sperm has been implicated in improving in vitro fertilization (IVF) results. We used the mouse model to investigate mechanisms of action of ATPe on sperm. ATPe treatment significantly enhanced IVF success as indicated by both rate of pronuclear formation and percentage cleavage to the 2-cell stage. However, ATPe did not increase the percentage of sperm undergoing spontaneous acrosomal exocytosis nor change the pattern of protein tyrosine phosphorylation normally observed in capacitated sperm. ATPe altered sperm motility parameters; in particular, both noncapacitated and capacitated sperm swam faster and straighter. The percentage of hyperactivated sperm did not increase in capacitated ATPe-treated sperm compared to control sperm. ATPe induced a rapid increase in the level of intracellular calcium that was inhibited by two distinct P2 purinergic receptor inhibitors, confirming that these receptors have an ionotropic role in sperm function. The observed motility changes likely explain, in part, the improved fertilizing capability when ATPe-treated sperm were used in IVF procedures and suggest a mechanism by which ATPe treatment may be beneficial for artificial reproductive techniques.

A strict infertility diagnosis has poor agreement with the clinical diagnosis entered into the Society for Assisted Reproductive Technology registry

Based on a recent review of the medical literature, a clinical diagnosis of infertility may not agree with strict criteria. Standardized definitions of diagnostic categories are essential for accurate patient prognosis and future research.

In vitro fertilization in the polycystic ovary syndrome patient: an update.

Polycystic ovary syndrome (PCOS) patients have posed significant challenges when treated for their infertility with in vitro fertilization and embryo transfer (IVF-ET). Their propensity for an exaggerated response to gonadotropin therapy places them at high risk for developing ovarian hyperstimulation syndrome (OHSS). Early OHSS is seen because of their hyper-responsiveness and the persistence in the circulation of the exogenously administered human chorionic gonadotropin (hCG). Late OHSS develops because of these patients’ relatively good prognosis for pregnancy with assisted reproductive technologies and the emergence of increasing amounts of endogenous hCG as pregnancy is established. Moreover, as undesirable as it may be, it may be necessary to resort to cycle cancellation to avoid the development of OHSS in high responders, like in patients with PCOS. Indeed, a 10.5% incidence of moderate to severe OHSS has been seen in PCOS patients, which is greater than the 0.5% to 4% observed in the general IVF population. A recent meta-analysis noted an odds ratio of 6.8 [95% confidence interval (CI) 4.9-9.6] for the development of OHSS in ultrasounddetermined PCO patients compared with those with normal-appearing ovaries on baseline ultrasound.5 Therefore, at any given moment, a busy IVF practice must deal with the delicate balance of stimulation and response exemplified in the challenges of treating PCOS patients. The present manuscript represents an update of the issues facing the clinician who recommends and treats infertile PCOS patients with IVF and builds on information previously presented.

Fertility preservation in female cancer patients

Recent diagnostic and therapeutic advances in pediatric oncology have led to greater survival rates in children with malignancies. However, while adolescent cancer therapies improve long-term survival, such treatments often lead to infertility, early menopause and long-term health problems related to early ovarian failure. As more young women survive childhood cancer and lead full lives, these concerns are becoming increasingly important. Faced with the diagnosis of cancer during the reproductive years, patients will have many questions, not only about the cancer and treatment itself but also with respect to future fertility. Will they be able to have children? Will the children be healthy? What technologies exist to help them preserve their fertility and what are the success rates? Can the cancer treatment allow a delay in order to accomplish fertility preservation? Clinicians must be armed with updated information to address these concerns and help guide patients through cancer treatment towards a healt...