Browsing by Subject "Semen"

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    Association between donor gamete use and supernumerary embryo disposition decisions.
    (Journal of assisted reproduction and genetics, 2023-02) Tsai, Shelun; Hynes, Jenna S; Zanolli, Nicole; Raburn, Douglas; Steiner, Anne Z

    Purpose

    The aim of this study is to determine if donor gamete use is associated with patients' decisions regarding disposition of supernumerary embryos.

    Methods

    Patients who intended to undergo an IVF cycle at a single academic center signed an embryo disposition consent form to indicate their disposition preferences for any supernumerary embryos. A retrospective chart review was performed to obtain the embryo disposition declarations and demographic information. The primary outcome was the distribution of embryo disposition choices between patients who used donor gametes compared to patients who did not use donor gametes. Fisher's exact test was used to compare groups. Logistic regression models were created to determine the association between donor gamete use and disposition decision after adjusting for patient age, body mass index, and nulliparity.

    Results

    Five hundred six patients were included. Ninety-one (18.0%) patients used donor gametes [46 (9.0%) donor oocytes, 52 (10.3%) donor sperm]. Patients using donor gametes differed from those not using donor gametes when making decisions concerning death of the patient (P < 0.01), simultaneous death (P = 0.04), separation (P < 0.01), discontinuation of ART (P = 0.01), and time-limited storage (P < 0.01). Most patients, regardless of donor or autologous gamete use, awarded embryos to themselves or their partner if given the option. For patients who did not choose this option, excess embryos were generally awarded to research or discarded rather than donating to another couple. Patients using donor gametes were more likely to award embryos to research over discarding.

    Conclusion

    Patients using donor gametes made different choices regarding supernumerary embryo disposition compared to patients not using donor gametes.
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    How Female-Female Competition Affects Male-Male Competition: Insights into Postcopulatory Sexual Selection from Socially Polyandrous Species.
    (The American naturalist, 2023-03) Lipshutz, Sara E; Torneo, Samuel J; Rosvall, Kimberly A
    AbstractSexual selection is a major driver of trait variation, and the intensity of male competition for mating opportunities has been linked with sperm size across diverse taxa. Mating competition among females may also shape the evolution of sperm traits, but the effect of the interplay between female-female competition and male-male competition on sperm morphology is not well understood. We evaluated variation in sperm morphology in two species with socially polyandrous mating systems, in which females compete to mate with multiple males. Northern jacanas (Jacana spinosa) and wattled jacanas (J. jacana) vary in their degree of social polyandry and sexual dimorphism, suggesting species differences in the intensity of sexual selection. We compared mean and variance in sperm head, midpiece, and tail length between species and breeding stages because these measures have been associated with the intensity of sperm competition. We found that the species with greater polyandry, northern jacana, has sperm with longer midpieces and tails as well as marginally lower intraejaculate variation in tail length. Intraejaculate variation was also significantly lower in copulating males than in incubating males, suggesting flexibility in sperm production as males cycle between breeding stages. Our results indicate that stronger female-female competition for mating opportunities may also shape more intense male-male competition by selecting for longer and less variable sperm traits. These findings extend frameworks developed in socially monogamous species to reveal that sperm competition may be an important evolutionary force layered atop female-female competition for mates.
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    What's fishy about protamine? Clinical use, adverse reactions, and potential alternatives.
    (Journal of thrombosis and haemostasis : JTH, 2023-07) Levy, Jerrold H; Ghadimi, Kamrouz; Kizhakkedathu, Jayachandran N; Iba, Toshiaki
    Protamine, a highly basic protein isolated from salmon sperm, is the only clinically available agent to reverse the anticoagulation of unfractionated heparin. Following intravenous administration, protamine binds to heparin in a nonspecific electrostatic interaction to reverse its anticoagulant effects. In clinical use, protamine is routinely administered to reverse high-dose heparin anticoagulation in cardiovascular procedures, including cardiac surgery with cardiopulmonary bypass. Despite the lack of supportive evidence regarding protamine's effectiveness to reverse low-molecular-weight heparin, it is recommended in guidelines with low-quality evidence. Different dosing strategies have been reported for reversing heparin in cardiac surgical patients based on empiric dosing, pharmacokinetics, or point-of-care measurements of heparin levels. Protamine administration is associated with a spectrum of adverse reactions that range from vasodilation to life-threatening cardiopulmonary dysfunction and shock. The life-threatening responses appear to be hypersensitivity reactions due to immunoglobulin E and/or immunoglobulin G antibodies. However, protamine and heparin-protamine complexes can activate complement inflammatory pathways and inhibit other coagulation factors. Although alternative agents for reversing heparin are not currently available for clinical use, additional research continues evaluating novel therapeutic approaches.