Insemination Research Articles

Peer Microaggressions and Social Skills among School-Age Children of Sexual Minority Parents through Assisted Reproduction: Moderation via the Child–Teacher Relationship

The impact of peer microaggressions and the child–teacher relationship on the social skills of children with sexual minority parents has received little attention. The current study used a mixed-method, multi-informant, two-wave longitudinal design to address this research gap. Thirty-seven children of lesbian mothers through donor insemination and 33 children of gay fathers though surrogacy (wave 1: Mage = 8.3 years, SD = 1.6; 51.4% female; wave 2: Mage = 9.9 years, SD = 1.7), all school-aged and residing in Italy, participated together with their 140 parents and 55 teachers. Approximately two-thirds of the children reported at least one peer microaggression and, on average, microaggressions were of a low intensity. Child–teacher relationships were of high quality (i.e., characterized by high safe haven–seeking and secure base use, and low conflict). Both parents and teachers reported high levels of child social skills. However, more intense W1 microaggressions predicted lower W2 social skills among children reporting a lower W1 child–teacher relationship quality, and greater W2 social skills among those reporting a higher W1 child–teacher relationship quality. These results support the child–teacher relationship as a potentially secure context in which children can “mentalize” negative experiences such as microaggressions and improve their social skills. In this vein, considering microaggression, attachment, and developmental intergroup theories, teachers must attune to the school experiences of children with sexual minority parents and cultivate caring classroom environments that are sensitive to family diversity.

371 Improving iui success after modified slow-release insemination: a prospective cohort study

Introduction: Previous studies also showed a higher IUI success rate after slow-release insemination instead of bolus injection. Aim of the study: To examine whether a modified slow-release insemination (SRI) increases the clinical pregnancy rate (CPR) after intrauterine insemination with partner semen (IUI-P) and donor semen (IUI-D) Methods: We studied the data of an ongoing prospective cohort study. During the period of July 2011 until December 2018, data from 2565 IUI-Ps in 989 women and 1995 IUI-Ds in 606 women were collected prospectively. As from January 2016 (period 2), the insemination procedure was performed by midwives instead of medical doctors. Instead of bolus injection of sperm a slow-release IUI was performed. Instead of ordinary logistic regression analysis we used a cluster-weighted generalized estimating equations (GEEs) for statistical analysis. Results of two periods (2011-2015 and 2016-2018) were examined for both homologous and donor inseminations. Results: Clinical pregnancy rates (presence of fetal heart beat at 7-8 weeks of gestation) ollowing IUI-P increased significantly from 9.0 % (period 1) to 13.4 % (period 2) (p = 0.001). In case of donor inseminations, clinical pregnancy rates increased from 16.5 % to 20.8 % (p = 0.088), a non-significant increase. Conclusion: The CPR after modified slow-release inseminations increased significantly after IUI with homologous semen. After using donor sperm the CPR increased from 16.6 % to 20.8 % per cycle with donor semen, a non-significant increase. Although our results were analysed in a prospective cohort study, a prospective randomised trial is needed to confirm our findings. We also have to examine whether our better results can be explained by the slow-release IUI, the patient-centred approach or both.

Are UK Policies and Practices for Regulated Donor Insemination Forcing Women to Find Unregulated Sperm Donors Online? A Perspective on the Available Evidence.

In recent years, there has been an increase in women obtaining donor sperm via unregulated websites and social media. In this article, we bring together the disparate evidence in this emerging field to consider whether restrictive UK policies and practices for regulated clinical donor insemination (DI) are a potential explanation for the growing use of the currently unregulated, online route to donor insemination. To this end, we examine the nature of the National Institute for Health and Care Excellence (NICE) guidelines, recent data provided by the Human Fertilisation and Embryology Authority (HFEA), and prior research on who uses online sperm donation and their reasons for doing so. In addition, we highlight why this issue is important by outlining some of the benefits and drawbacks of the unregulated route. We argue that, whilst there are many factors driving the unregulated route to DI, restrictive UK policies and practices for regulated DI might be one of these. We conclude that turning our attention to structural barriers, such as regulated DI policies and practices, is necessary to produce more definitive evidence of this potential issue, and that adopting a Reproductive Justice framework could lead to more equitable provision of regulated DI services.

Sperm donors versus long-term mates: a comparison of preferences of heterosexual and lesbian women

The present study aimed to explore whether lesbian women’s preferences for a sperm donor or a long-term mate show a pattern similar to those of heterosexual women. Three hundred and eighty-three donor insemination patients, of whom 278 were heterosexual and 105 were lesbian, completed a questionnaire comprising a series of 35 traits and rated the importance of each trait in a sperm donor and again in a long term mate. Results showed that traits relating to socioeconomic status, genetic background and general health, physical appearance, and personality were rated by lesbian women as more important in a long-term mate than in a sperm donor. It was further found that both heterosexual and lesbian women attached higher importance to the socioeconomic status, personality and physical appearance of the long-term mate than of the sperm donor; heterosexual women attached similar importance to the genes and health of a long-term mate and a sperm donor, while lesbian women attached greater importance to the genetic background and general health of the sperm donor than those of a long-term mate. The implications and interpretations of the findings are discussed in light of Trivers’ parental investment theory.

National survey of donor-conceived individuals who requested information about their sperm donor-experiences from 17 years of identity releases in Sweden.

STUDY QUESTIONWhat characterizes the group of donor-conceived (DC) individuals who request information about their identity-release sperm donor in Sweden, and what are their experiences of disclosure, information receipt and donor contact?SUMMARY ANSWERFollowing three decades of identity-release donation in Sweden, few DC individuals have requested donor information with varying experiences of information receipt and donor contact.WHAT IS KNOWN ALREADYIn 1985, Sweden was the first country worldwide to enact legislation that gave DC individuals the right to obtain identifying information about their donor. Since then, identity-release gamete donation has become available in many countries but there is limited knowledge about the individuals who request donor information.STUDY DESIGN, SIZE, DURATIONA nation-wide cross-sectional survey study was performed at all seven University hospitals that provided donation treatment in Sweden during 1985–2002. During this period only donor insemination to heterosexual couples was permitted. Inclusion criteria were being 18 years of age or older, conceived with donor sperm and having requested information about the donor by December 2020. Recruitment was performed during 2016–2020.PARTICIPANTS/MATERIALS, SETTING, METHODSA total of 60 individuals had requested information about their donor. Of these, 53 were approached and 40 individuals, representing 34 families, accepted study participation (75% response rate). Participants completed a postal survey with the WHO-10 well-being index and study-specific questions about experiences of disclosure, motivations for requesting donor information, receipt of information, as well as intentions and experiences of donor contact. Independent t-test and chi-square tests were used to compare ratings of participants with early and late disclosure.MAIN RESULTS AND ROLE OF CHANCEOf ∼900 DC individuals who had reached adult age, a total of 60 (≈7%) had requested information about the donor. Most of the 40 study participants (78%) made their requests within 2 years after reaching 18 years of age, or following disclosure at later ages (up to 32 years). Several participants had adult DC siblings in the family who had not requested any donor information. All except five participants received identifying information about the donor from the clinic. However, some donors had died or lacked contact information. Among those participants who were able to contact their donor, 41% had done so at the time of the study, while a third of the participants were unsure about potential contact. Several had met the donor in person and a few were in regular contact. About half of the participants had been informed about their donor conception in adolescence or adulthood (age 12–32), and there were significant differences between participants based on age at disclosure. Compared to those with early disclosure, participants with late disclosure were significantly more likely to be dissatisfied with the timing of their disclosure (P = 0.021), to react with negative emotions (P < 0.001), and to subsequently contact the donor (P = 0.047).LIMITATIONS, REASONS FOR CAUTIONThe limited population available for inclusion resulted in a small sample size, despite a high response rate. In addition, men’s lower participation rate must be taken into consideration when interpreting the results.WIDER IMPLICATIONS OF THE FINDINGSThe small number of individuals requesting information about their identity-release sperm donor is surprising. While not all DC individuals appear to be interested in donor information, it is reasonable to assume that some are unaware of their donor conception and thus unable to make informed decisions regarding their genetic origins. During the coming years, young women and men in many countries will become eligible to access identifying information about their donor. In order to meet the needs of these individuals, and to support positive outcomes for all involved parties, it is essential that adequate protocols and resources are developed.STUDY FUNDING/COMPETING INTERESTFinancial support from The Swedish Research Council. There are no conflicts of interest to declare.TRIAL REGISTRATION NUMBERN/A.

The Effect of Insemination Time, Season and Insemination Method on Calf Gender in Holstein Cattle

The aim of this article is to determine the effect of insemination time, season and insemination method on calf gender in cattle. In the study, 792 records of inseminations and calving data between 2010-2019 were evaluated. The onset of estrus was determined based on mounting behavior. Inseminations were carried out between 0-6, 6-12, 12-18 hours after the onset of estrus. At the same time, inseminations were evaluated according to the seasons. Of the inseminations, 582 were artificial insemination and 210 were natural insemination. While insemination time and insemination method had no effect on calf gender, seasonal effect was found to be significant. Keywords: Holstein, Insemination Time, Gender DOI: 10.7176/JSTR/7-10-03

Why Are the Proportions of In-Vitro Fertilisation Interventions for Same Sex Female Couples Increasing?

Same-sex female couples who wish to become pregnant can choose donor insemination or in-vitro fertilization (IVF)—a technique intended for infertile women. In general, women in same-sex female partnerships are no more likely to be infertile than those in opposite sex partnerships. This article investigates data available from the Government Regulator of UK fertility clinics—the Human Fertilization and Embryology Authority, which is the only data available worldwide on same-sex female couples and their fertility choices. IVF is increasing both in absolute numbers and relative proportions year on year in the UK, compared to licensed donor insemination for same-sex female couples. As IVF has greater human and financial costs than donor insemination, policies should not encourage it as the first choice for fertile women requiring sperm. Commercial transactions are taking place where fertile lesbians receive cut price, and arguably unnecessary, IVF intervention in exchange for selling their eggs to be used for other infertile customers. If women are not told about the efficacy of fresh vs. frozen semen, and the risks of egg ‘sharing’ or intra-couple donation, exploitation becomes possible.

Prevalence of Brucellosis in Cattle under Different Management Systems in Mbale District, Eastern Region of Uganda

The research study was conducted on prevalence of Brucellosis in cattle under different management systems in Mbale District, Eastern Region of Uganda. The research design adopted was a purposive sampling. 48 respondents from different farms were selected using a random sampling to allow equal representation of the farms. The data were collected using both blood samples and questionnaires. A total of 78 serum samples collected from different cattle were serologically assessed using Rose Bengal Plate Test (RBPT) and Serum Agglutination Test (SAT). The high sero-prevalence of 37.5% was recorded in female cows followed by male bulls (20.0%) and female calves (20.0%). Bull calves and heifers showed negative result with RBPT and SAT (0.0%). A total of 24(30.7%) and 22(28.2%) were recorded for RBPT and SAT respectively. However, although there was higher prevalence of Brucellosis in communal grazing than the rest of other grazing systems, there was no statistical significant difference between Brucellosis and grazing systems (p&gt;0.05). Similarly, considering the type of breeding methods of fertilization, there was a statistically significant relationship between the type of breeding (artificial and natural insemination) methods and management system practiced (p&lt;0.05). The study concluded that contamination of common grazing environment was due to aborted foetuses which is accompanied by shedding of large number of Brucella species and that there was lack of knowledge on the causative agents, as well as mode of transmission. The researchers recommend that cattle grazing systems that limit mixing of herds should be encouraged to reduce the contamination of common grazing environment.

Impact of the COVID-19 Pandemic on Access to Fertility Care: ARetrospective Study at a University-Affiliated Fertility Practice.

ObjectiveTo elucidate the impact of the COVID-19 pandemic on access to fertility services.MethodsA retrospective quality improvement study was conducted at a university-affiliated fertility practice in southwestern Ontario. Annual procedural volumes for intrauterine and donor inseminations (IUI/DI), in vitro fertilization and intracytoplasmic sperm injections (IVF/ICSI), and frozen embryo transfers (FET) during the COVID-19–affected year were compared with mean annual volumes from the 2 preceding years. In addition, volumes for the same procedures were compared between the first quarter of 2021 and mean first quarter volumes from 2018 to 2019. Piecewise linear regressions were conducted to evaluate whether any changes in monthly procedural volume were attributable to the COVID-19 pandemic.ResultsIn 2020, our fertility practice attained the mean annual volumes of 89.7% for IUI/DI, 69.0% for IVF/ICSI, and 60.6% for FET. In contrast, in 2021, we performed mean first quarter volumes of 130.1% for IUI/DI, 164.3% for IVF/ICSI, and 126.8% for FET. The slopes of the pre- and post–COVID-19 segments of the piecewise linear regressions were significantly different for IUI/DI (P < 0.001) and IVF/ICSI (P = 0.001), but not for FET (P = 0.133).ConclusionThe COVID-19 pandemic resulted in decreased annual volumes of medically assisted reproductive procedures at a university-affiliated fertility practice in southwestern Ontario. Impact on monthly procedural volume was confirmed for IUI/DI and IVF/ICSI by linear regression. Local adaptations helped compensate and exceed expected volumes in 2021. As a result, the COVID-19 pandemic resulted in a short-lived limitation in access to fertility care.

Life\u2019s continuation: repro-tech, biogenetic affinity, and racial capitalism

This paper examines the affinity ties of biological and familial whiteness in ART as evident in the 2014 Illinois Northern District Court case of Cramblett v. Midwest Sperm Bank—where a white mother filed a wrongful birth suit and sought legal compensation for the loss of perceived genetic similarity and giving birth to a ‘black’ child via donor insemination. Applying critical legal and critical race studies to the case and engaging its surrounding media, the paper considers what Cramblett can tell us about loss—as it is related to notions of value and property within an overarching system of racial capitalism. This paper considers how race, value, and property inter-articulated in Cramblett through notions of biogenetic relations and familial whiteness within the organization of family; how these ideas travel through to investments in life—and its continuation—as a form of racial property (for some); and what this case can tell us about broader operations of structural racism and the role of biomedicine (and law) within these operations. Ultimately, the paper shows that biogenetic affinity in ARTs condition life’s continuation in ways that resecure the disparities of racial capitalism.

Analysis of parental abnormal chromosomal karyotype and subsequent live births in Chinese couples with recurrent pregnancy loss

The frequency and distribution of chromosomal abnormalities and the impact of parental chromosomal aberration on the pregnancy outcomes of couples with recurrent pregnancy loss remains controversial. 3235 RPL couples who experienced two or more miscarriages before 20 weeks were diagnosed in our tertiary referral hospital during 2008–2018 and included in the single-center retrospective cohort study covering a 10-year period. Chromosome aberration was detected in 121 (3.74%) among 3235 RPL couples which included 75 female and 46 male cases at an individual level. 101 cases were structural aberrations including balanced translocations in 46(38.0%) cases, Robertsonian translocations in 13(10.7%) cases, inversions in 42(34.7%) cases and 20(16.5%) cases were numerical aberrations. 121 carriers and 428 non-carriers were followed up for two years, 55 carriers and 229 non-carriers were subsequent pregnant after diagnosis by natural conception or intrauterine insemination. The frequency of carriers to have a health newborn was not significantly different with non-carriers (72.7% vs. 71.2%, adjusted P = 0.968). This study described the majority of carriers were balanced translocations and chromosome aberrations had a limited influence on live birth rate from the present data. The results of the study also remind us that natural conception may be also a good alternative rather than PGD (Pre-implantation Genetic Diagnosis) which is common in many other reproductive centers for such patients.

Reproductive Ethics and Family

Reproductive Ethics and Family

Comparison of reproductive performance of AI- and natural service-sired beef females under commercial management.

The objective of this study was to assess differences in reproductive performance of natural service and artificial insemination (AI) sired beef females based on pregnancy outcomes, age at first calving, and calving interval. Data were sourced from 8,938 cows sired by AI bulls and 3,320 cows sired by natural service bulls between 2010 and 2017. All cows were in a commercial Angus herd with 17 management units located throughout Virginia and represented spring and fall calving seasons. All calves were born to dams managed with estrus synchronization. Pregnancy was analyzed with generalized linear mixed models and other reproductive measures with linear mixed models in R. Six models were evaluated with the dependent variables of pregnancy status at the first diagnosis, pregnancy status at the second diagnosis, pregnancy type (AI or natural service) at the first diagnosis, pregnancy type at the second diagnosis, calving interval, and age at first calving. Independent variables differed by model but included sire type of the female (AI or natural service), prebreeding measures of age, weight, and body condition score, postpartum interval, sex of the calf nursing the cow, and management group. No differences were observed between AI- and natural service-sired females based on pregnancy status at first and second pregnancy diagnosis (P > 0.05). Sire type was only found to be significant for age at first calving (P < 0.05) with AI-sired females being 26.6 ± 1.6 d older at their first calving, which was expected because AI-sired females were born early in the calving season making them older at breeding. Surprisingly, age and body condition score were not significant predictors of pregnancy (P > 0.05). Body weight at breeding was not significant for pregnancy (P > 0.05) but was significant for age at first calving (P < 0.05). These data suggested that lighter heifers calved earlier which contradicts our original hypothesis. Overall, commercial Angus females sired by AI or natural service bulls had similar reproductive performance. Factors that were commonly associated with reproductive success were not significant in this commercial Angus herd managed with estrus synchronization. Given the size of these data, the importance of body condition, age, and weight should be reassessed in modern genetics and management practices.

Investigation of Foot-and-Mouth Disease Outbreaks in Dairy Cattle from Kageshwari and Shankharapur Municipalities, of Kathmandu, Nepal and Associated Risk Factors from March to April 2020

Foot and mouth disease (FMD) is endemic in Nepal and significantly impacts the livelihood of farmers, national economy, and trade of Nepal. However, outbreak investigations are not frequently conducted, and there have been limited studies to understand the associated risk factors. A case-control study was performed in dairy cattle farms of Shankharapur and Kageshwari Municipalities, Kathmandu from March to April 2020 to describe the outbreak and identify the risk factors associated with FMD. There were 31 case farms, while 62 farms were selected as control farms (1:2). The information from case and control farms was collected by semi-structured questionnaire survey through field visits and observations. The univariable and multivariable logistic regressions were performed. The farm-level prevalence of FMD was 25.2% (n=31/123). Among the FMD affected farms, the proportion of positive farms in Shankharapur (61.3% (19/31)) was significantly higher than Kageshwori (38.7% (12/31)). The final multivariable logistic regression analysis identified four variables: cattle purchased within 14 days (OR=12.9; CI=2.4-69.5), milk market distance less than two kilometers from the farm (OR=32.7; CI=5.8-186.3), sharing of the bull from other farms for natural insemination (OR=5.7; CI=1.2-26.8), and no vaccination against FMD in the past six months (OR=19.1; CI=2.0-186.2) as significant risk factors for the occurrence of FMD. This study suggests farmers vaccinate their dairy cattle with FMD vaccine as per the vaccination schedule suggested by the veterinarians, practice quarantine measures when new animals are introduced to their farms, practice biosecurity measures in their farms, and do not use bulls from areas where there are ongoing FMD outbreaks.

Obedient Men and Obsessive Women: Donor Insemination, Gender and Psychology in Belgium

AbstractDrawing on contemporary studies and oral history interviews, this article analyses psychiatric evaluations of heterosexual couples requesting donor insemination in Belgium in the 1970s. It contains two interrelated arguments. First, it reassesses the reason why mental health professionals were incorporated into fertility clinics. In response to negative assumptions about the mental stability of candidates seeking donor insemination, they had to act as gatekeepers. This finding contradicts earlier research, which linked the integration of mental health professionals in reproductive medicine to the growing awareness of the emotional consequences of infertility and to the exclusivity of in vitro fertilisation. Second, this article shows that psychiatric evaluations were influenced by both traditional gender roles and newer models of equality. As the mirror of a society that was changing at different speeds, they reflected both the transformation of traditional ideals of family, sex and marriage and the discomfort sparked by these changes.

“Catholic, but not According to the Rules”: Assisted Reproduction and Catholic Doctors in Belgium, 1940s–1980s

This article elucidates how Catholic doctors in Belgium, a dominantly Catholic country that was home to the largest Catholic university in Europe, creatively handled church teachings on assisted reproduction from roughly the 1940s until the 1980s. Catholic thought on reproductive medicine is mostly represented as restrictive and conservative, but this is not the full picture. On the contrary, this article reveals that many Catholic moralists and physicians looked for loopholes within church teachings, creating ‘Catholic’ versions of assisted reproductive technologies. A few progressive Catholics fundamentally questioned the authority of the Vatican, justifying donor insemination and in‐vitro fertilisation by means of personalist ethics. By drawing attention to the diverse ways in which Catholics in Belgium negotiated their own moral understandings of assisted reproduction, this article adds a new dimension to recent histories of contraception, which complicate narratives of conflict between religion, science, and sexual liberation.

Artificial insemination of rabbits: current state and practical possibilities of the method

Relevance. Rabbits have great reproductive and productive potential. In the industrial (conveyor) system of rabbit production, the brood stock of the rabbit farm is divided into production groups and artificially inseminated on a strictly fixed day of the week on the 4th or (more often) 11th day of lactation. Only clinically healthy and well-fed females are allowed to insemination. It is shown that with an intensive rate of reproduction of the herd from one rabbit, it is possible to receive from 40...55 to 60...65 weaned rabbits and produce up to 120 kg of rabbit meat annually. Methods. The technological processes and practical possibilities of the method of artificial insemination of rabbits are considered and analyzed. Results . Work on artificial insemination of rabbits is carried out in the following order: collecting semen from the bucks, assessing the quality of ejaculate, diluting and short-term storing sperm in vitro, stimulating sexual activity and diagnosing the sexual receptivity of suckling female rabbits, intravaginal insemination of does with hormonal induction of ovulation. Sperm from male rabbits is obtained on a receptive female with the help of an artificial vagina: two ejaculates collected once a week with an interval of at least 15 min. The process of collecting semen on an artificial vagina takes average 26.2 seconds. After macro-and microscopic evaluation, the ejaculate is diluted 1:5...1:10 with a medium based on Tris-or Hepes-buffer. For dilution and short-term storage of sperm directly in the farm environment (up to 24...48 hours), ready-to-use commercial extenders are also used (for example, Lepus®, Cortalap®, Merk III®, Formula® etc.). The selection of rabbits for insemination is carried out according to the signs of estrus and sexual reaction of the female to the male. 48 hours before the planned insemination, all suckling rabbits of the production group are injected with the gonadotropic drug folligon (at a dose of 20 IU). Exogenous gonadotropic stimulation induces cyclic growth of follicles, synchronizes the manifestation of sexual activity in rabbits of the production group, improves reproductive efficiency of rabbit does in term of fecundity (fertility and prolificacy). The technique of artificial insemination of rabbits is quite simple. Using a semi-automatic syringe with a removable disposable sterile catheter, sperm is inserted deeply into the rabbit vagina in a volume of 0.5 ml. With an effective organization of work, an insemination technician and an assistant can inseminate up to 150 female rabbits in 1 hour (with simultaneous hormonal induction of ovulation).Good results, almost as with natural insemination, are obtained when using freshly obtained diluted or diluted chilled sperm for insemination with a shelf life of up to 6 ... 12 hours.

Outcomes of donor versus partner sperm in intrauterine insemination in women aged 38years and older.

To compare pregnancy rates of donor versus partner sperm in intrauterine insemination (IUI) cycles in women aged 38years and above. A retrospective cohort study was performed using data from 944 women aged 38-43years old who underwent a combined 1596 IUI cycles at an academic fertility clinic in Montreal, Canada between February 2009 to April 2018. Partner sperm was used in 1421 cycles (89.0%), and donor sperm was inseminated in 175 cycles (11.0%). Mean ages of the women were 39.8 (±1.5) and 40.2 (±1.6) years in the partner and donor insemination groups, respectively (P<0.001). Positive serum (β human chorionic gonadotropin) pregnancy rate in the partner sperm group was 9.0% (n=128) whereas that in the donor insemination group was 9.7% (n=17) (P=0.759). Clinical pregnancy rates were 5.8% (n=83) and 8.0% (n=14) in the respective groups (P=0.260). There were five multiple gestation (twin) pregnancies in the cohort, three in those undergoing IUI with partner sperm and two in those undergoing IUI with donor sperm. In women aged 38-43years undergoing IUI with controlled ovarian stimulation, using donor sperm, compared with partner sperm, did not increase rate of pregnancy.

Using egg yolk in a TRIS-Equex STM paste extender for freezing of dog semen is superior to egg yolk plasma, also after addition of lecithin and catalase

We compared the results of using egg yolk plasma (EYP) instead of egg yolk (EY) in a TRIS-based Equex STM Paste freezing extender system for dog semen [25]. We also tested whether the addition of lecithin and catalase to the EYP extenders would improve results. Fractionated semen collection was done in 17 stud dogs and the sperm rich fraction diluted with different extenders in 2 steps: (I) TRIS-fructose-citric acid extender (TRIS) containing 20% egg yolk (EY) and 3% glycerol [25], (II) TRIS containing 20% egg yolk plasma (EYP) and 3% glycerol, and (III) TRIS containing 20% EYP and 0.8% lecithin (EYP-L) and 3% glycerol. After equilibration the second dilution step was done: samples with (I) were diluted with TRIS-EY with 7% glycerol and 1% Equex STM paste [25]; samples with (II) and (III) were divided in 2 aliquots each, and one part diluted with TRIS-EYP or TRIS-EYP-L, both containing 7% glycerol and 1% Equex STM paste, and the other one part with the same extenders containing additionally 300 I.U./mL catalase. After freezing and thawing, samples were analyzed by CASA and sperm chromatin structure assay (SCSA); reactive oxygen species (ROS), degree of apoptosis and zona binding ability were determined. Semen samples with TRIS-EY with a final concentration of 5% glycerol and 0.5% Equex STM paste [25] showed best post thaw progressive motility (P), most intact cells, lowest percentage of ROS, acrosome damages, dead and apoptotic cells. Curvilinear velocity (VCL), DNA fragmentation, morphological abnormalities and zona binding ability did not differ between groups. Replacement of egg yolk by EYP increased the ROS and late apoptotic cells. Addition of lecithin and catalase to EYP containing extenders decreased motility and increased complete apoptosis. We conclude that egg yolk is superior to EYP in the here investigated extenders. The TRIS-based extender [25] with EYP could not be improved by addition of lecithin and catalase; however, in-vivo fertilization capacity of the here examined extenders remains to be investigated.

Is pre-freeze sperm preparation more advantageous than post-freeze?

SummaryHuman sperm cryopreservation is characterised to this day by sub-optimal success rates. Interestingly, a traditional approach to improving post-thaw outcome has been to integrate standard sperm preparation techniques into freezing protocols as a means of selecting sperm with the highest fertilisation potential prior to insemination. However, no consensus has been reached yet regarding the optimal timing (before or after freezing) of this selection step. Following analysis of a total of 20 human semen samples, which were divided into two aliquots prepared by density gradient centrifugation either before or after freezing, this study demonstrated higher post-thaw total (P < 0.0001), progressively motile (P = 0.005) and vital (P < 0.0001) sperm counts for frozen-prepared semen samples. The present study suggests that direct insemination with frozen-prepared sperm with minimal intervening post-thaw processing might be a more advantageous approach to current clinical practices, particularly for donor and patient intrauterine insemination programmes. Further research into cryopreservation-induced coiled sperm tail morphology is also warranted.Lay summaryFreezing and storing of sperm in liquid nitrogen (’sperm cryopreservation') is the current method of choice for preserving the fertility of a wide scope of men. Nevertheless, sub-optimal sperm survival is still associated with traditional cryopreservation methods, namely 'slow freezing', and may affect fertility treatment success rates. Interestingly, a widely applied approach for selecting high-quality sperm before treatment has been to incorporate 'sperm preparation' techniques, such as density gradient centrifugation, in slow freezing protocols. There is, however, an ongoing debate regarding which is the optimal timing of this selection step: before or after freezing. In this study, we collected 20 human semen samples which were divided into two portions and subjected to density gradient centrifugation either before or after freezing. Post-thaw semen analyses demonstrated significantly improved sperm counts (P < 0.05) when density gradient centrifugation was performed before freezing, thus suggesting this approach to be more advantageous for current clinical practices.