Human spermatozoa accumulate in vitro in diluted follicular fluids obtained from follicles from which the eggs have been fertilized. Using capillary assays under a variety of experimental conditions (ascending or descending gradients of follicular fluid, or no gradient at all) and microscopic assays in which individual spermatozoa could be followed, we found that the sperm accumulation in follicular fluid was the result of both sperm chemotaxis and chemokinesis and eventually hyperactivation-like motility. We determined the optimal conditions for sperm accumulation, which involved sperm preincubation (possibly to induce sperm capacitation) and proper dilution of follicular fluid. In all the assays, the net accumulation was low, probably reflecting the chemotactic responsiveness of only a small fraction of the sperm population at any given time. We partially fractionated follicular fluid in a Centricon microconcentrator (Amicon, Danvers, MA) and by acetone precipitation, and found that at least one of the chemotactic factors is a small (< 10-kDa) molecule that is probably nonhydrophobic. This is the first time that sperm chemotaxis and chemokinesis in response to a follicular factor(s) in mammals has been established and has been distinguished from other processes that might cause sperm accumulation. The physiological significance of these findings is discussed.
Poor response to ovarian stimulation for assisted reproduction treatment is a therapeutic challenge. Oocyte donation may be unacceptable to some patients, and many couples opt to continue with treatment despite low follicle numbers. Minimal data are available regarding conception rates in poor responders who elect to undergo oocyte retrieval. This study summarizes the outcome of assisted reproduction treatment in poor responders who produced four or fewer oocytes during ovarian stimulation, in order to provide better counselling to such patients in the future. Embryo transfers were performed in 208 of 300 cycles demonstrating poor ovarian response. Pregnancy rate (PR) (15.9%) was significantly higher in patients in whom four oocytes were retrieved, compared with patients in whom one or two oocytes were retrieved (2.3 and 4.3% respectively). Younger patients (< or =34 years) had significantly higher PR (19.5%) compared with older patients (> or =35 and < or =39 years, PR 7.2% and > or =40 years, PR 1.5% respectively). One hundred and twenty-six age-matched normal responders in whom three embryos were transferred had higher implantation rates (15.3%) and PR (37.3%) compared with poor responders in whom three embryos were transferred (6.6 and 16.6% respectively; P < 0.05). In this regard, patient age, number of oocytes retrieved and number of embryos available for transfer determine prognosis for the success of IVF in patients who respond to ovarian stimulation with four or fewer follicles for assisted reproduction treatment.
Postponement of child bearing and maternal age at first pregnancy are on the rise, contributing considerably to an increase in age-related infertility and the demand for assisted reproductive technologies (ART) treatment. This brings to the infertility clinics many women with low ovarian reserve and poor ovarian response (POR) to conventional stimulation. The Bologna criteria were released to standardize the definition of POR and pave the way for the formulation of evidence-based, efficient modalities of treatment for women undergoing IVF-ET. More than four years have passed since the introduction of these criteria and the debate is still ongoing whether a revision is due. Women with POR comprise several sub-groups with diverse baseline distinctiveness, a major issue that has fueled the discussion. Although antral follicle count (AFC) and anti-Müllerian hormone (AMH), are considered good predictors of ovarian reserve, their threshold values are still not universally standardized. Different definitions for sonographic AFC and diverse assays for AMH are held responsible for this delay in standardization. Adding established risk factors to the criteria will lead to more reliable and reproducible definition of a POR, especially in young women. The original criteria did not address the issue of oocyte quality, and the addition of risk factors may yield specific associations with quality vs. quantity. Patient’s age is the best available criterion, although limited, to predict live-birth and presumably oocyte quality. High scale studies to validate these criteria are still missing while recent evidence raises concern regarding over diagnosis.
Objective To answer the question of whether oxytocin induction of labour should be discontinued when active labour begins. Design We enrolled patients admitted for induction of labour with oxytocin. Exclusion criteria for induction of labour included non-vertex presentation, past history of more than one caesarean delivery, multiple pregnancies, non-reassuring fetal heart rate before induction of labour and estimated fetal weight of more than 4250 g. Setting
The expression of hedgehog (Hh) genes, their receptor, and the co-receptor in mice, rat, and bovine ovaries were investigated. RT-PCR of ovarian transcripts in mice showed amplification of transcripts for Indian (Ihh) and desert (Dhh) Hh, patched 1 (Ptch1), and smoothened (Smo) genes. Semi-quantitative RT-PCR and northern blot analyses showed that whole ovarian Ihh and Dhh transcripts decreased 4-24 h after hCG versus 0-48 h after pregnant mares serum gonadotrophin treatment in mice, whereas mouse Ptch1 and Smo transcripts were expressed throughout the gonadotropin treatments. Quantitative real-time RT-PCR (qRT-PCR) revealed that the expression of the Hh-patched signaling system with Ihh mRNA abundance in granulosa cells was greater, whereas Smo and Ptch1 mRNA abundance was less in theca cells of small versus large follicles of cattle. In cultured rat and bovine theca-interstitial cells, qRT-PCR analyses revealed that the abundance of Gli1 and Ptch1 mRNAs were increased (P!0.05) with sonic hedgehog (SHH) treatment. Additional studies using cultured bovine theca cells indicated that SHH induces proliferation and androstenedione production. IGF1 decreased Ihh mRNA abundance in bovine granulosa cells. The expression and regulation of Ihh transcripts in granulosa cells and Ptch1 mRNA in theca cells suggest a potential paracrine role of this system in bovine follicular development. This study illustrates for the first time Hh activation of Gli1 transcriptional factor in theca cells and its stimulation of theca cell proliferation and androgen biosynthesis.
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