Cryopreserved testicular spermatozoa among patients with azoospermia.

PURPOSE: To investigate cryopreserved testicular spermatozoa among patients with azoospermia. METHODS: In this retrospective study spanning from October 1993 to December 2021, we examined men diagnosed with azoospermia who underwent testicular spermatozoa cryopreservation. Data from medical records included utilization and disposal of sperm samples, age at initial cryopreservation. We analyzed the data over 20 years using Kaplan-Meier curves, compared age with the log-rank test, and assessed hazard ratios (HR) with 95% confidence intervals (CI) using Cox regression analysis. RESULTS: A total of 356 patients with a mean age of 32.1 ± 6 were included. Of these, 225 patients utilized thawed testicular sperm for fertility treatments, with 118 patients using all their frozen straws and 107 patients partially using their stored straws. Additionally, 29 patients opted for disposal (six patients partially used their testicular spermatozoa before disposal), resulting in 108 patients who neither used nor disposed of their straws. From a laboratory standpoint, nearly 90% of patients contributed a single testicular sample, which was subsequently divided and cryopreserved as straws, with a median of 4 straws per sample. Notably, in the older age group (> 35 years old), there were a significantly lower usage rate and a higher disposal rate compared to the younger age groups (p < 0.05 for both), corroborated by univariable Cox analysis. CONCLUSIONS: This extensive study unveils unique patterns in the preservation and disposal of testicular spermatozoa among azoospermic patients. Most patients utilize a significant portion of their stored samples, while older patients tend to use their testicular spermatozoa less frequently.

[THE EFFECT OF ETHNICITY ON THE AGE OF SINGLE PATIENTS APPLYING FOR SPERM DONATION].

INTRODUCTION: Sperm banks have shifted from assisting heterosexual couples with male infertility to primarily serving single women and female couples through medical services, reflecting advances in fertility treatments and societal changes. AIMS: Evaluate demographic changes among single women who have applied for sperm donation during 30 years in the State of Israel. METHODS: This retrospective cohort study includes 4265 single women who received sperm donation between January 1992 and December 2021, at a tertiary medical center. We divided the follow-up period into 6 groups of 5 years each. A comparison was made of the demographic characteristics of single women applying for sperm donation in different periods according to: 1) age at the beginning of the treatment; 2) ethnic origin - 7 ethnic groups. RESULTS: The average age of single women who received sperm donation was 38.2±4.4 years. The average age of patients decreased from 39.58 years in 1997-1992 to 38.08 years in 2017-2021 (p-value<0.05). Ashkenazic Jews (38.4%) and Sephardic Jews (37.7%) were the most common ethnic origins among single women, with Arab women comprising only 0.2%. Single Jewish women of Ashkenazi descent seek sperm donation treatment almost a year earlier than their Sephardic counterparts (Arab countries and North Africa). CONCLUSIONS: Single Israeli women opting for early sperm donation carries significant clinical, social, and economic implications. Women from conservative social backgrounds appear to be less inclined to seek sperm donation as single individuals or tend to delay this option until a later age, in contrast to women from liberal backgrounds.

The effect of COVID-19 vaccination during IVF stimulation on cycle outcomes- a retrospective cohort study.

The effect of the mRNA-BNT162b2 vaccine administered prior to fertility treatments has been addressed in several studies, presenting reassuring results. Cycle outcomes of patients receiving the vaccine during the stimulation itself have not been previously described. This retrospective cohort study included patients who received mRNA-BNT162b2-vaccine during the stimulation of fresh IVF cycles, between January-September 2021, age matched to pre-stimulation vaccinated patients and to non-vaccinated patients. Demographics, cycle characteristics and cycle outcomes were compared between groups. A total of 132 in-treatment vaccinated patients (study group), 132 pre-treatment vaccinated and 132 non-vaccinated patients that underwent fresh IVF cycles were included. Mean time from vaccination to retrieval in the study group was 6.68 days (SD 3.74; range 0-12). Oocyte yield was similar between groups (9.35 versus10.22 and 10.05 respectively; p=0.491). A linear regression model demonstrated no effect of vaccination before or during the stimulation, on oocyte yield (p>0.999). Clinical pregnancy rates (30 % versus 30 % versus 28 %) and ongoing pregnancy rates (25 % for all groups) did not differ between groups. In a logistic regression model for clinical pregnancy rates, vaccine administration and timing of vaccination were not a significant factor. This is the first study reporting the outcome of the mRNA BNT162b2 vaccine administration during the IVF stimulation itself. The vaccine administration had no impact on fresh IVF treatment outcomes compared to pre-treatment vaccinated or non-vaccinated patients. This adds to the growing evidence of COVID-19 vaccine safety in relation to fertility treatments and enables more flexibility regarding timing of vaccine administration.

Follicular challenge test to predict suboptimal response to gonadotropin releasing hormone agonist trigger in elective oocyte cryopreservation cycles.

This prospective study aimed to test the ability of follicular GnRH agonist challenge test (FACT) to predict suboptimal response to GnRH agonist trigger, assessed by LH levels post ovulation trigger in non-medical oocyte cryopreservation program. The study included 91 women that underwent non-medical fertility preservation. On day two to menstrual cycle, blood tests were drawn (basal Estradiol, basal FSH, basal LH, Progesterone) and ultrasound (US) was performed. On that evening, the women were instructed to inject 0.2 mg GnRH agonist (FACT) and arrive for repeated blood workup 10-12 h later in the next morning, followed by a flexible antagonist protocol. LH levels on the morning after ovulation trigger were compared to FACT LH levels. The results demonstrated that LH levels following agonist ovulation trigger below 15IU/L occurred in 1.09% of cycles and were predicted by FACT, r = 0.57, p < 0.001. ROC analysis demonstrated that FACT LH > 42.70 IU/L would predict LH post trigger of more than 30 IU/L with 75% sensitivity and 70% specificity, AUC = 0.81. LH levels post trigger also displayed significant positive correlation to basal FSH (r = 0.35, p = 0.002) and basal LH (r = 0.54, p < 0.001). LH levels post ovulation trigger were not associated with total oocytes number or maturity rate. The strongest correlation to the number of frozen oocytes was progesterone levels post agonist trigger (r = 0.746, p < 0.001). We concluded that suboptimal response to agonist trigger, as assessed by post trigger LH levels was a rare event. FACT could serve as an adjunct pre-trigger, intracycle tool to predict adequate LH levels elevation after agonist ovulation trigger. Future studies should focus on optimization of agonist trigger efficacy assessment and prediction, especially in high responders.

Autologous sperm usage after cryopreservation-the crucial impact of patients' characteristics.

BACKGROUND: The wide implementation of sperm freezing presents a growing burden on sperm banks. OBJECTIVES: To evaluate sperm freezing and usage patterns over 30 years, according to demographic parameters of age at first cryopreservation and number of children, and indication for cryopreservation. MATERIAL AND METHODS: This retrospective, population based, cohort study included all sperm cryopreservation cases performed at a tertiary referral center from October 1993 to December 2021, among patients aged 18 years and older. First, we determined the interval between first sperm sample and use. Then, we examined sperm usage separately for: (1) age, comparing patients grouped into 5-year age cohorts; (2) paternal status according to number of children; (3) indication, comparison among seven indications. Secondary analysis included correlations between main age groups and paternal status versus the four most common indications found. RESULTS: During the study period 1490 men who cryopreserved sperm met the inclusion criteria. Average age at cryopreservation of the first sample was 33.9 ± 8.1 years. Average age at first sperm use was 37 ± 8.5 years. Cumulative sperm usage was 38.7% after 17.8 years. Increasing age was associated with progressive increase in sperm usage rate and shorter preservation period. Use significantly decreased with increasing number of children. Examination of seven reasons for sperm cryopreservation found the highest cumulative sperm usage was related to azoospermia (67.7%), followed by functional cryopreservation (39.3%), oligoasthenoteratospermia (27.3%), other (26.5%), patient's request (24%), cancer (19%), and systemic disease (7.2%). Secondary analysis defined specific usage patterns mainly related to age and indication, with less of an effect based on the number of children. DISCUSSION AND CONCLUSION: After decades of cryopreservation, the paradigm of sperm cryopreservation is mostly related to cancer patients. This should be reevaluated and evolve to include broader patient-targeted factors and perceptions.

Sperm Donors' Identity Disclosure: Is It REALLY Crucial? For Whom?

OBJECTIVE: To study the preference of sperm donors with identity disclosure (ID) versus anonymous donors (AD) and to understand if this selection affects clinical outcomes in an Israeli population. METHODS: This retrospective study included patients who chose imported sperm donation during 2017-2021. Of these, 526 used their own (autologous) oocytes and 43 patients used donated oocytes (DO). The primary endpoint was the type of chosen donor with ID versus AD. We examined the tendency toward ID according to demographic parameters and the theoretical impact of donor-type selection on reproductive outcome and compared patients who performed cycles with autologous oocytes with those using DO. RESULTS: Single women had a significantly higher probability of choosing sperm donors with ID than heterosexual couples (55.6% vs. 33.3%, OR 2.5, CI 95% 1.52-4.11, P < 0.001). Although not significant, same-sex couples were more likely to choose sperm donors with ID than heterosexual couples (49.1% vs. 33.3%, OR 1.93, CI 95% 0.97-3.85, P = 0.06). Sperm donor samples, 2501 vials, were imported. It was performed 698 intra-uterine insemination and 812 in vitro fertilization cycles were performed, respectively, resulting in 283 pregnancies without differences between patients who chose sperm donors with ID versus AD sperm. No significant differences were observed regarding the option for sperm donors with ID between patients using DO (44.2%) and those using autologous oocytes (51.3%). CONCLUSION: While ID is important for a certain section (mainly single) of recipients, it is far from the only dominant factor during donor selection. Sperm donation type does not impact clinical outcomes.

Critical Demographic Changes among Sperm Donation Recipients Over Three Decades.

BACKGROUND: Sperm banks initially focused on providing sperm donation (SD) to heterosexual couples grappling with severe male infertility. Notable advancements in fertility treatments and sociological trends have broadened the scope of SD toward single women and same sex female couples. OBJECTIVES: To evaluate SD recipient characteristics over the last three decades in Israel according to demographic parameters. METHODS: This retrospective cohort study included 5489 women who received SD between January 1992 and December 2021 from a tertiary referral center. We divided the overall period into six groups of five years each. A comparison of demographic characteristics of women who received SD in different periods was performed according to age at the beginning of the treatment, marital status (single women and same sex female couples, heterosexual couples), and ethnic origin. RESULTS: The average age of women who received SD was 37.02 ± 5.36 years. The average patient age rose from 35.08 years in 1992-1997 to 37.43 years in 2017-2021 (P-value < 0.01). The use of SD was more common among single women and same sex female couples compared to heterosexual couples in later years. Regarding single and same sex female couple, the percentage of SD recipients increased radically from 33% to 88.1% (P-value < 0.01). CONCLUSIONS: Modern sperm banks treat older patients in non-heterosexual relationships. These trends encompass not only medical implications (e.g., in vitro fertilization vs. intrauterine insemination) but also delve into the personal and sociological impact experienced by both patients and offspring.

Motivational stimuli to donate sperm among non-donor students.

BACKGROUND: Sperm banks face a continuously evolving gap between the increasing demand for sperm donation (SD) vs. limited available reserve. To improve donors' recruitment and increase supply, motivations towards SD should be investigated specifically among young men who have the potential to become donors. Our aim was to evaluate factors which increase and decrease predisposition to donate sperm among non-donor students, who represent a "potential pool" for possible donors' recruitment. RESULTS: Ninety-three men fulfilled the questionnaire with mean age of 28.2 ± 4.5 years. The most powerful incentive to donate sperm was financial reward followed by a willingness to help others to build a family (3.8 and 3.4, respectively). The most dominant consideration to decline donation was the fear of anonymity loss and future regret (4 and 3.8). While participants' willingness for anonymous SD was fair (2.8), the open-identity donation was rated significantly lower (1.75, p < 0.01). Familiarity with recipients and offspring had lower scores (1.9-2.2) as well. CONCLUSIONS: Young single men represent a suitable cohort for anonymous donation. Financial reward and willingness to help others are important positive incentives while anonymity preservation is crucial to maintain their willingness towards SD. Regulatory shifting towards open-identity SD necessitates the establishment of an alternative "potential pool" population as a reliable source to recruit donors.

RéSUMé: CONTEXTE: Les banques de sperme font face à un écart en constante évolution entre la demande croissante de dons de sperme et les réserves disponibles limitées. Pour améliorer le recrutement des donneurs et augmenter l'offre, les motivations à l'égard du don de sperme devraient être étudiées spécifiquement chez les jeunes hommes qui ont le potentiel de devenir donneurs. Notre objectif était d'évaluer les facteurs qui augmentent et diminuent la prédisposition au don de sperme chez les étudiants non-donneurs, qui représentent un « bassin potentiel ¼ pour le recrutement possible de donneurs. RéSULTATS: Ninety-three hommes ont rempli le questionnaire avec un âge moyen de 28,2±4,5 ans. L'incitation la plus puissante à donner du sperme était la récompense financière, suivie de la volonté d'aider les autres à fonder une famille (3,8 et 3,4, respectivement). La considération la plus dominante pour refuser le don était la peur de perdre l'anonymat et les regrets futurs (4 et 3.8). Alors que la volonté des participants de faire un don anonyme de sperme était passable (2,8), le don d'identité ouverte a été jugé significativement plus faible (1,75, p<0,01). La familiarité avec les receveurs et la progéniture avait également des scores plus faibles (1,9-2,2). CONCLUSIONS: Les jeunes hommes célibataires représentent une cohorte appropriée pour le don anonyme. La récompense financière et la volonté d'aider les autres sont des incitations positives importantes, tandis que la préservation de l'anonymat est cruciale pour maintenir leur volonté de donner du sperme. L'évolution réglementaire vers le don de sperme à identité ouverte nécessite l'établissement d'une population alternative de « bassin potentiel ¼ comme source fiable pour recruter des donneurs.

ABCC4 is a PGE2 efflux transporter in the ovarian follicle: A mediator of ovulation and a potential non-hormonal contraceptive target.

The role of prostaglandins (PGs) in the ovulatory process is known. However, the role of the ATP binding cassette subfamily C member 4 (ABCC4), transmembrane PG carrier protein, in ovulation remains unknown. We report herein that ABCC4 expression is significantly upregulated in preovulatory human granulosa cells (GCs). We found that PGE2 efflux in cultured human GCs is mediated by ABCC4 thus regulating its extracellular concentration. The ABCC4 inhibitor probenecid demonstrated effective blocking of ovulation and affects key ovulatory genes in female mice in vivo. We postulate that the reduction in PGE2 efflux caused by the inhibition of ABCC4 activity in GCs decreases the extracellular concentration of PGE2 and its ovulatory effect. Treatment of female mice with low dose of probenecid as well as with the PTGS inhibitor indomethacin or Meloxicam synergistically blocks ovulation. These results support the hypothesis that ABCC4 has an important role in ovulation and might be a potential target for non-hormonal contraception, especially in combination with PGE2 synthesis inhibitors. These findings may fill the gap in understanding the role of ABCC4 in PGE2 signaling, enhance the understanding of ovulatory disorders, and facilitate the treatment and control of fertility.

Treatment safety of ART cycles with extremely high oestradiol concentrations using GnRH agonist trigger.

RESEARCH QUESTION: Are IVF treatments with extremely high peak oestradiol levels and gonadotrophin releasing hormone (GnRH) agonist trigger associated with higher complication rates? DESIGN: A retrospective cohort study including patients from two large medical centres treated between 2019 and 2021. A study group with extremely high peak oestradiol levels (≥20,000 pmol/l on the day of ovarian stimulation, or ≥15,000 pmol/l on the previous day) and a control group with normal range oestradiol levels (3000-12000 pmol/l) that received GnRH agonist triggering. Patients were surveyed about complaints and medical care related to ovum retrieval and medical files were reviewed. Major complication rates and the need for medical assistance were compared. RESULTS: Several differences between the study and control group were observed because of the study design: mean age was 33.01 ± 5.14 versus 34.57 ± 4.52 (P < 0.001), mean peak oestradiol levels was 26645.34 ± 8592.57 pmol/l versus 7229.75 ± 2329.20 pmol/l (P < 0.001), and mean number of oocytes were 27.55 ± 13.46 versus 11.67 ± 5.76 (P < 0.001) for the study and control group, respectively. Major complications and hospitalization rates were similar between the study and control groups (three [1.25%] versus one [0.48%]; P = 0.62 and three [1.25%] versus two [0.96%]; P = 1.0, respectively). Thirty-six patients (15.1%) in the study group and 11 (5.3%) in the control group sought medical care after retrieval, mostly due to abdominal pain, without the need for further workup or hospitalization (P < 0.001). CONCLUSIONS: Extremely high oestradiol levels were not associated with thromboembolic events, higher major complication or hospitalization rates, and therefore may be considered safe. Nevertheless, patients may be informed of possible higher rates of discomfort, mostly abdominal pain. Larger studies are warranted to confirm our results.

What can we learn about posthumous sperm retrieval after extra long-term follow-up?

PURPOSE: To describe spermatozoa extraction rate by testicular sperm extraction (TESE) for posthumous sperm retrieval (PMSR) and examine harvest time impact on sperm motility; to compare long-term sperm usage between married vs. single deceased men. METHODS: This retrospective study included all PMSR cases in Shamir Medical Center during 2003-2021. We evaluated sperm cryopreservation according to latency time after death. Then, we assessed sperm usage according to Israeli PMSR regulations. RESULTS: The study included 69 (35 married and 34 singles) deceased men with average age of 30.3 ± 7.8 years. Sperm was cryopreserved in 65 cases (94.2%) after maximum and average harvest time of 40 and 16.5 ± 8.1 h, respectively. Motile sperm extraction was associated with significantly shorter harvest time compared with non-motile sperm (13.8 ± 7.3 vs. 18.7 ± 8.1 h, p = 0.046). Sperm usage among married deceased was significantly higher than single (15.6% vs. 0%, p = 0.05). Disposal requests were lower among single compared to married men relatives without reaching statistical difference. Eventually, single men had significantly higher rate of non-used cryopreserved samples (93.8% vs 69.6%, p = 0.01). CONCLUSION: This large long-term cohort study demonstrates high efficacy of PMSR. We found significant harvest latency time difference between motile and non-motile preserved sperm. Clinical sperm usage rate justifies the efforts for PMSR among married deceased. However, contradicting policy on the topic of single men (which implies liberal sperm preservation but rigid prevention of usage) results with high non-used sperm rate and relatives' extremely sophisticated emotional burden.

Endometrial compaction is associated with increased clinical and ongoing pregnancy rates in unstimulated natural cycle frozen embryo transfers: a prospective cohort study.

PURPOSE: To investigate the association between endometrial compaction and pregnancy rates in unstimulated natural cycle frozen embryo transfers. DESIGN: A single-center prospective cohort study. Endometrial thickness by transvaginal ultrasound and blood progesterone levels on the day of ovulation and the day of embryo transfer were evaluated in patients undergoing natural cycle frozen embryo transfer. Compaction was defined as > 5% decrease in endometrial thickness between ovulation day and day of transfer. Clinical and ongoing pregnancy rates in cycles with and without compaction were compared. RESULTS: Seventy-one women were included, of which 44% had endometrial compaction, with similar rates when subdividing the patients by day of transfer (day 3 or day 5). Clinical and ongoing pregnancy rates were higher in the compaction group compared to the non-compaction group (0.58 vs. 0.16, P < 0.001; 0.52 vs. 0.13, P < 0.001 respectively). Subdividing by degree of compaction > 10% and > 15% revealed similar pregnancy rates as > 5%, with no added benefit to higher degrees of compaction. CONCLUSIONS: About half the patients in our study undergoing unstimulated natural cycle frozen embryo transfer experienced compaction of the endometrium, occurring as early as day 3 post-ovulation. This was significantly correlated with increased clinical and ongoing pregnancy rates.

The impact of past COVID-19 infection on pregnancy rates in frozen embryo transfer cycles.

PURPOSE: To study the effect of SARS-CoV-2 infection on pregnancy rates in frozen embryo transfer (FET) cycles. METHODS: A retrospective cohort study including women under the age of 42 with documented SARS-CoV-2 infection up to 1 year prior to treatment, undergoing FET cycles in the first half of 2021, with transfer of embryos generated prior to the infection. Controls were SARS-CoV-2 non-diagnosed, non-vaccinated women matched by age, number, and day of embryo transfer. Demographic and cycle characteristics and outcomes were compared. RESULTS: Forty-one recovered women and 41 controls were included. Pregnancy rates were 29% and 49% respectively (p = 0.070). Stratification by time from SARS-CoV-2 infection to transfer into ≤ 60 and > 60 days revealed a difference in pregnancy rates, with women in the COVID group having lower pregnancy rates if infected in proximity to the transfer (21% vs. 55%; p = 0.006). In a logistic regression model, infection was a significant variable (p = 0.05, OR 0.325, 95% CI 0.106-0.998). Logistic regression applied on the subgroup of women infected in proximity to the transfer further strengthened the univariate results, with COVID-19 remaining a significant parameter (p = 0.005, OR 0.072, 95% CI 0.012-0.450). CONCLUSIONS: In FET cycles of patients with past SARS-CoV-2 infection, in which oocytes were retrieved prior to infection, decreased pregnancy rates were observed, specifically in patients who recovered less than 60 days prior to embryo transfer. Pending further studies, in cases of FET cycles with limited number of embryos, postponing embryo transfer for at least 60 days following recovery from COVID-19 might be considered when feasible.

Coronavirus disease 2019 vaccination and infertility treatment outcomes.

OBJECTIVE: To assess the influence of coronavirus disease 2019 (COVID-19) messenger ribonucleic acid vaccine on ovarian response and in vitro fertilization (IVF) treatment outcomes. DESIGN: A retrospective cohort study. SETTING: A tertiary university-affiliated medical center and a private medical center. PATIENT(S): The study included a total of 400 patients, 200 vaccinated women and 200 age-matched unvaccinated women, who underwent IVF in January-April 2021. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The mean number of oocytes retrieved and clinical pregnancy rates in vaccinated vs. unvaccinated patients. RESULT(S): A total of 200 patients underwent oocyte retrieval 14-68 days after receiving COVID-19 vaccination. No difference was found in the mean number of oocytes retrieved per cycle (10.63 vs. 10.72) between vaccinated and unvaccinated patients. Among 128 vaccinated and 133 unvaccinated patients who underwent fresh embryos transfers, no difference was demonstrated in the clinical pregnancy rates (32.8% vs. 33.1%), with 42 and 44 clinical pregnancies, respectively. The fertilization rates and mean number of cryopreserved embryos were similar between the 2 groups in freeze-all cycles (55.43% vs. 54.29% and 3.59 vs. 3.28, respectively). Among vaccinated and unvaccinated patients who underwent fresh embryo transfers, no difference was noted in the fertilization rate (64.81% vs. 61.98%) and transferred embryos' quality. Regression models applied demonstrated no effect of the vaccine on oocyte yields and pregnancy rates. CONCLUSION(S): The COVID-19 messenger ribonucleic acid vaccine did not affect the ovarian response or pregnancy rates in IVF treatment. Women should be vaccinated for COVID-19 before attempting to conceive via IVF treatments, given the higher risk of severe illness in pregnant women.

IVF under COVID-19: treatment outcomes of fresh ART cycles.

STUDY QUESTION: Does prior severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in women undergoing fertility treatments affect the outcomes of fresh ART cycles? SUMMARY ANSWER: SARS-CoV-2 infection does not affect fresh ART treatment outcomes, except for a possible long-term negative effect on oocyte yield (>180 days postinfection). WHAT IS KNOWN ALREADY: A single previous study suggested no evidence that a history of asymptomatic or mild SARS-CoV-2 infection in females caused impairment of fresh ART treatment outcomes. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study, including all SARS-CoV-2 infected women who underwent fresh ART cycles within a year from infection (the first cycle postinfection), between October 2020 and June 2021, matched to non-diagnosed controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients from two large IVF units in Israel who were infected with SARS-CoV-2 and later underwent fresh ART cycles were matched by age to non-diagnosed, non-vaccinated controls. Demographics, cycle characteristics and cycle outcomes, including oocyte yield, maturation rate, fertilization rate, number of frozen embryos per cycle and clinical pregnancy rates, were compared between groups. MAIN RESULTS AND THE ROLE OF CHANCE: One hundred and twenty-one infected patients and 121 controls who underwent fresh ART cycles were included. Oocyte yield (12.50 versus 11.29; P = 0.169) and mature oocyte rate (78% versus 82%; P = 0.144) in all fresh cycles were similar between groups, as were fertilization rates, number of frozen embryos per cycle and clinical pregnancy rates (43% versus 40%; P = 0.737) in fresh cycles with an embryo transfer. In a logistic regression model, SARS-CoV-2 infection more than 180 days prior to retrieval had a negative effect on oocyte yield (P = 0.018, Slope = -4.08, 95% CI -7.41 to -0.75), although the sample size was small. LIMITATIONS, REASONS FOR CAUTION: A retrospective study with data that was not uniformly generated under a study protocol, no antibody testing for the control group. WIDER IMPLICATIONS OF THE FINDINGS: The study findings suggest that SARS-CoV-2 infection does not affect treatment outcomes, including oocyte yield, fertilization and maturation rate, number of good quality embryos and clinical pregnancy rates, in fresh ART cycles, except for a possible long-term negative effect on oocyte yield when retrieval occurs >180 days post-SARS-CoV-2 infection. Further studies are warranted to support these findings. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: 0010-21-HMC, 0094-21-ASF.

An impressive capacity for cold tolerance plasticity protects against ionoregulatory collapse in the disease vector Aedes aegypti.

The mosquito Aedes aegypti is largely confined to tropical and subtropical regions, but its range has recently been spreading to colder climates. As insect biogeography is tied to environmental temperature, understanding the limits of A. aegypti thermal tolerance and their capacity for phenotypic plasticity is important in predicting the spread of this species. In this study, we report on the chill coma onset (CCO) and recovery time (CCRT), as well as low-temperature survival phenotypes of larvae and adults of A. aegypti that developed or were acclimated to 15°C (cold) or 25°C (warm). Cold acclimation did not affect CCO temperatures of larvae but substantially reduced CCO in adults. Temperature and the duration of exposure both affected CCRT, and cold acclimation strongly mitigated these effects and increased rates of survival following prolonged chilling. Female adults were far less likely to take a blood meal when cold acclimated, and exposing females to blood (without feeding) attenuated some of the beneficial effects of cold acclimation on CCRT. Lastly, larvae suffered from haemolymph hyperkalaemia when chilled, but cold acclimation attenuated the imbalance. Our results demonstrate that A. aegypti larvae and adults have the capacity to acclimate to low temperatures, and do so at least in part by better maintaining ion balance in the cold. This ability for cold acclimation may facilitate the spread of this species to higher latitudes, particularly in an era of climate change.

HAS2-AS1 is a novel LH/hCG target gene regulating HAS2 expression and enhancing cumulus cells migration.

BACKGROUND: The cumulus expansion process is one of the LH mediated ovulatory processes. Hyaluronan synthase 2 (HAS2) regulates the synthesis of hyaluronic acid, the main component of the cumulus expansion process. Recently, the lncRNA HAS2 antisense RNA 1 (HAS2-AS1) was identified in our global transcriptome RNA-sequencing of novel ovulation associated genes. The role of HAS2-AS1 in HAS2 regulation w.as studied previously with contradictive results in different models but not in the ovary. Taken together the induction of HAS2-AS1 and the important role of HAS2 in the cumulus expansion process, we hypothesize that HAS2-AS1 regulate HAS2 expression and function in the ovary. Therefore we undertook to study the expression, regulation, and possible functional role of HAS2-AS1 in the human ovary. RESULTS: HAS2-AS1, located within the HAS2 gene that was highly regulated in our library. We found that HAS2-AS1 express mainly in cumulus cells (CCs). Furthermore, HAS2-AS1 showed low expression in immature CCs and a significant increase expression in mature CCs. Functional studies reveal that inhibition of HAS2-AS1 by siRNA caused decrease expression of HAS2. Furthermore, inhibition of HAS2-AS1 by siRNA results in decrease migration of granulosa cells. CONCLUSIONS: Our results suggest that HAS2-AS1 is an LH/hCG target gene that plays a positive role in HAS2 expression and thus might play a role in regulating cumulus expansion and migration.

An optimized model for hCG stimulation of human mural granulosa cell culture.

Ovarian follicular development and ovulation in mammals is a highly-regulated process. Most of the current knowledge of ovarian processes was obtained from the studies of non-human models. Molecular studies on human ovarian processes suffer from lack of material and appropriate research tools. Mural granulosa cells (MGCs) culture is a major tool for studying the effect of different substances but a major problem for using these primary MGCs is their unresponsiveness to hCG stimulation at the time of oocyte retrieval. It is acceptable that MGCs regain responsiveness during days in culture but when the best time is and how to accelerate the regenerative process are unknown. The aim of the current study was to establish an optimized protocol which will provide a practical and efficient tool to examine the effect of LH/hCG on different downstream targets in luteinized MGCs. hCG effects were examined according to days in culture and hCG stimulation time. As read-out, we analyzed the gene expression of known hCG targets, protein production, and progesterone secretion. Our results show that with a daily medium exchange, the strongest effect was achieved already 4 days after seeding. On day 4, hCG stimulation triggers two major patterns of gene expression. Early induced genes were highly expressed 6-8 h after hCG, while 24 h of hCG stimulation was needed for late induced genes. Based on our results, we suggest daily medium exchange for 4 days before adding hCG and examine its effect 6 and 24 h later.

Anti-diuretic activity of a CAPA neuropeptide can compromise Drosophila chill tolerance.

For insects, chilling injuries that occur in the absence of freezing are often related to a systemic loss of ion and water balance that leads to extracellular hyperkalemia, cell depolarization and the triggering of apoptotic signalling cascades. The ability of insect ionoregulatory organs (e.g. the Malpighian tubules) to maintain ion balance in the cold has been linked to improved chill tolerance, and many neuroendocrine factors are known to influence ion transport rates of these organs. Injection of micromolar doses of CAPA (an insect neuropeptide) have been previously demonstrated to improve Drosophila cold tolerance, but the mechanisms through which it impacts chill tolerance are unclear, and low doses of CAPA have been previously demonstrated to cause anti-diuresis in insects, including dipterans. Here, we provide evidence that low (femtomolar) and high (micromolar) doses of CAPA impair and improve chill tolerance, respectively, via two different effects on Malpighian tubule ion and water transport. While low doses of CAPA are anti-diuretic, reduce tubule K+ clearance rates and reduce chill tolerance, high doses facilitate K+ clearance from the haemolymph and increase chill tolerance. By quantifying CAPA peptide levels in the central nervous system, we estimated the maximum achievable hormonal titres of CAPA and found further evidence that CAPA may function as an anti-diuretic hormone in Drosophila melanogaster We provide the first evidence of a neuropeptide that can negatively affect cold tolerance in an insect and further evidence of CAPA functioning as an anti-diuretic peptide in this ubiquitous insect model.

Outcome of immature oocytes collection of 119 cancer patients during ovarian tissue harvesting for fertility preservation.

PURPOSE: Few clinical options for fertility preservation are available to females with cancer, and data about clinical outcomes is limited. Potential supplementary approaches to fertility preservation include retrieval of immature oocytes followed by in vitro maturation (IVM) and storage. The aim of this study was to evaluate post-thawing outcomes of immature oocytes collected both by transvaginal aspiration and from excised ovarian tissue. METHODS: We conducted a retrospective cohort study of patients treated in a single tertiary center. We reviewed the records of 119 cancer patients who underwent ovarian tissue cryopreservation and immature oocyte harvesting for fertility preservation. All embryos and oocytes that were frozen and thawed were included in the study. Post-thawing outcomes were evaluated. RESULTS: Thirty-five stored embryos from eight patients were thawed. Twenty-nine embryos survived (82% survival rate) and were transferred. Six oocytes were thawed, two oocytes survived, and no oocytes were fertilized. Only one PCOS patient became pregnant, resulting in the normal delivery of a healthy baby. CONCLUSIONS: Although a relatively high number of mature oocytes and embryos can be stored with the combined procedure, the limited rate of pregnancies represents a poor reproductive outcome. Therefore, this approach should be reserved for special groups with limited options.