A case is reported of a patient with critically low anti-mullerian hormone (AMH) having successful 'rescue' oocyte retrieval in natural in vitro fertilization (IVF) cycle 24 hours after the initial procedure had resulted in no oocyte being collected. Following administration of 10,000 units human chorionic hormone (hCG) a second retrieval was performed 24 hours after the first, producing one Me...

Precise control of the timing of translational activation of dormant mRNAs stored in oocytes is required for normal progression of oocyte maturation. We previously showed that Pumilio1 (Pum1) is specifically involved in the translational control of cyclin B1 mRNA during Xenopus oocyte maturation, in cooperation with cytoplasmic polyadenylation element-binding protein (CPEB). It was reported tha...

Immature oocytes benefit from nutrient modification of the follicular environment by the surrounding cumulus mass. However, the oxygen concentration that the oocyte may be exposed to could be lower than the antral follicular concentration due to the metabolism of surrounding cumulus cells. Using metabolic data previously determined, we have developed a mathematical model of O(2) diffusion acros...

The universal signal for egg activation at fertilization is a rise in cytoplasmic Ca(2+) with defined spatial and temporal kinetics. Mammalian and amphibian eggs acquire the ability to produce such Ca(2+) signals during a maturation period that precedes fertilization and encompasses resumption of meiosis and progression to metaphase II. In Xenopus, immature oocytes produce fast, saltatory Ca(2+...

OBJECTIVE To report the first case of fertility preservation in a premenarcheal female by use of controlled ovarian hyperstimulation and oocyte cryopreservation. DESIGN Case report. SETTING Reproductive endocrinology and infertility unit of a tertiary care university-based medical center. PATIENT(S) A 13-year-old premenarcheal female with Tanner stage 3 breast development and Tanner stage...

Glutathione (GSH) is thought to play critical roles in oocyte function including spindle maintenance and provision of reducing power needed to initiate sperm chromatin decondensation. Previous observations that GSH concentrations are higher in mature than immature oocytes and decline after fertilization, suggest that GSH synthesis may be associated with cell cycle events. To explore this possib...

BACKGROUND Polycystic ovary syndrome (PCOS) is associated with metabolic disturbances which include impaired insulin signalling and glucose metabolism in ovarian follicles. The oocyte is metabolically dependent upon its follicle environment during development, but it is unclear whether PCOS or polycystic ovarian (PCO) morphology alone affect oocyte metabolism and energy-demanding processes such...

BACKGROUND Ovarian follicle development is a complex process. Paracrine interactions between somatic and germ cells are critical for normal follicular development and oocyte maturation. Studies have suggested that the health and function of the granulosa and cumulus cells may be reflective of the health status of the enclosed oocyte. The objective of the present study is to assess, using an in ...

STUDY QUESTION Does heparin ablate the advantageous effects of cyclic adenosine mono-phosphate (cAMP) modulators during pre-in vitro maturation (IVM) and have a deleterious effect in standard oocyte IVM? SUMMARY ANSWER Heparin interrupts energy metabolism and meiotic progression and adversely affects subsequent development of oocytes under conditions of elevated cAMP levels in cumulus-oocyte ...

Background: Successful in vitro maturation (IVM) of oocytes is an important step for production of livestock through assisted reproductive techniques including somatic cell nuclear transfer (SCNT). Obtaining an optimal duration for maturation of oocyte is essential, since over exposure to maturation medium results in oocyte aging, while under exposure leads to production of immature incompetent...