The number of drones to inseminate a queen with has little potential for optimization of honeybee breeding programs.

BACKGROUND: Mating control is a crucial aspect of honeybee breeding. Instrumental insemination of queens gives the breeder maximum control over the genetic origin of the involved drones. However, in addition to the drones' descent, the breeder's control also extends over the number of drones to use for inseminations. Thus far, this aspect has largely been ignored in attempts to optimize honeybee breeding schemes. The literature provides some comparisons between single drone inseminations (SDI) and multi drone inseminations (MDI) but it is unclear whether the number of drones used in MDI is a relevant parameter for the optimization of honeybee breeding programs. METHODS: By computer simulations, we investigated the effect of the number of drones per inseminated queen in breeding programs that relied on best linear unbiased prediction (BLUP) breeding values. We covered a range of 1 to 50 drones per queen and observed the developments of genetic gain and inbreeding over a period of 20 years. Hereby, we focused on insemination schemes that take the drones for one queen from a single colony. RESULTS: SDI strategies led to 5.46% to 14.19% higher genetic gain than MDI at the cost of 6.1% to 30.2% higher inbreeding rates. The number of drones used in MDI settings had only a negligible impact on the results. There was a slight tendency that more drones lead to lower genetic gain and lower inbreeding rates but whenever more than five drones were used for inseminations, no significant differences could be observed. CONCLUSION: The opportunities to optimize breeding schemes via the number of drones used in inseminations are very limited. SDI can be a viable strategy in situations where breeders are interested in genetically homogeneous offspring or precise pedigree information. However, such strategies have to account for the fact that the semen from a single drone is insufficient to fill a queen's spermatheca, whence SDI queens will not build full-strength colonies. When deciding for MDI, breeders should focus on collecting enough semen for a succesful insemination, regardless of how many drones they need for this purpose.

Sexual conflict and sexual networks in bed bugs: the fitness cost of traumatic insemination, female avoidance and male mate choice.

Sexual conflict is prevalent among animals and is primarily caused by the fact that the optimal mating rates are often higher in males than in females. While there is a growing appreciation that females can also gain from multiple matings, we still know relatively little about which sex controls the observed mating rates and how close it is to the optimal female mating rates. To address this issue, we tracked female bed bugs (Cimex lectularius) inseminated daily versus weekly and found that weekly inseminated females lived longer and produced over 50% more offspring. In a follow-up experiment employing a social network framework, we placed 24 bed bugs into a semi-naturalistic arena and recorded all sexual interactions. While recently inseminated females did not avoid males more often, they were more frequently rejected by males. Finally, we tracked avoidance behaviour in a single cohort of female bed bugs as they received six successive daily inseminations. Avoidance rates increased and insemination durations decreased with increasing number of prior inseminations. Overall, our results indicate high costs of polyandry. Although females possess some plastic avoidance strategies, the observed rates of insemination fall closer to the male rather than female optimum.

Identification of genes associated with sperm storage capacity in hens at different times after insemination by RNA-seq and Ribo-seq.

BACKGROUND: Sperm storage capacity (SSC) determines the duration of fertility in hens and is an important reproduction trait that cannot be ignored in production. Currently, the genetic mechanism of SSC is still unclear in hens. Therefore, to explore the genetic basis of SSC, we analyzed the uterus-vagina junction (UVJ) of hens with different SSC at different times after insemination by RNA-seq and Ribo-seq. RESULTS: Our results showed that 589, 596, and 527 differentially expressed genes (DEGs), 730, 783, and 324 differentially translated genes (DTGs), and 804, 625, and 467 differential translation efficiency genes (DTEGs) were detected on the 5th, 10th, and 15th days after insemination, respectively. In transcription levels, we found that the differences of SSC at different times after insemination were mainly reflected in the transmission of information between cells, the composition of intercellular adhesion complexes, the regulation of ion channels, the regulation of cellular physiological activities, the composition of cells, and the composition of cell membranes. In translation efficiency (TE) levels, the differences of SSC were mainly related to the physiological and metabolic activities in the cell, the composition of the organelle membrane, the physiological activities of oxidation, cell components, and cell growth processes. According to pathway analysis, SSC was related to neuroactive ligand-receptor interaction, histidine metabolism, and PPAR signaling pathway at the transcriptional level and glutathione metabolism, oxidative phosphorylation, calcium signaling pathway, cell adhesion molecules, galactose metabolism, and Wnt signaling pathway at the TE level. We screened candidate genes affecting SSC at transcriptional levels (COL4A4, MUC6, MCHR2, TACR1, AVPR1A, COL1A1, HK2, RB1, VIPR2, HMGCS2) and TE levels(COL4A4, MUC6, CYCS, NDUFA13, CYTB, RRM2, CAMK4, HRH2, LCT, GCK, GALT). Among them, COL4A4 and MUC6 were the key candidate genes differing in transcription, translation, and translation efficiency. CONCLUSIONS: Our study used the combined analysis of RNA-seq and Ribo-seq for the first time to investigate the SSC and reveal the physiological processes associated with SSC. The key candidate genes affecting SSC were screened, and the theoretical basis was provided for the analysis of the molecular regulation mechanism of SSC.

Change in the incidence of stillbirth in Japanese Black cattle during the animal movement restrictions and suspended insemination.

We aimed to characterize the change in the incidence of stillbirth (IS) in Japanese Black cattle during and after animal movement restrictions and suspended insemination because of a foot-and-mouth disease (FMD) outbreak in Miyazaki Prefecture in 2010. Calving data from 2006 to 2018 were collected from approximately 900 farms. Post-FMD period was divided into three based on the median IS per month (1.80%): period 1 (May 2011 to February 2013), period 2 (March 2013 to August 2015), and period 3 (September 2015 to December 2018). The ISs were similar during the Pre-FMD period and Post-FMD period 1, then substantially decreased during Post-FMD period 2 (p < .05), before returning to the value before the FMD outbreak period during Post-FMD period 3. Compared with the Pre-FMD period, Post-FMD period 1 was associated with a higher proportion of calvings by primiparous cows and Post-FMD period 2 was associated with a smaller number of calvings per month (p < .05). There were high ISs in primiparous cows during the Pre-FMD period, Post-FMD period 1, and Post-FMD period 3 (p < .05), but not during Post-FMD period 2. In summary, after the animal movement restrictions and suspended insemination introduced because of the FMD outbreak, the IS temporarily decreased and consequently returned to the pre-FMD level.

Males conditionally inseminate at three female body locations according to female mating history and female maturity status in a squid.

In some squids, such as those in the family Loliginidae, upon copulation, females receive and store male-delivered sperm capsules, spermatangia, at two different body locations: the buccal membrane and the distal end of the oviduct. This insemination site dimorphism is associated with alternative reproductive strategies. However, in Loliolus sumatrensis, a species of Loliginidae, the females possess three insemination sites: buccal membrane (BM), basal left IV arm (ARM) and lateral head behind the left eye (EYE), therefore we studied such the unusual phenomena. We developed microsatellite markers and genotyped the paternity of each spermatangium on three sites. We found multiple paternity at every single site and simultaneous usage of all three sites by a few males. The seasonal dynamics of a population in the Seto Inland Sea revealed a set priority for the initial use of insemination sites as BM, followed by ARM and then EYE, whereas the maximum number of stored spermatangia was greater in EYE > ARM > BM. Female maturity status was correlated with the usage pattern of insemination sites but not with the number of stored spermatangia at any insemination site. These results suggest that a male squid inseminates at different locations according to female mating history and female maturity status.

The puncture mechanics: an example from the bed bug Cimex lectularius showing traumatic insemination using the paramere.

Cimicidae are well-known for traumatic insemination, and males pierce females with their parameres and transfer sperm through them. The shape of parameres is relatively stable in the family, but in some genera, the paramere is elongated, appearing less resistant against lateral deflection. To understand the mechanical limitations of the paramere, we studied its penetration mechanics of the common bed bug, Cimex lectularius. We examined the post-abdominal morphology, paramere geometry and material properties and conducted breaking stress experiments on the paramere under wet and dry conditions. Mechanical property gradients are present with the paramere tip as the stiffest region and the base as the most flexible one. These mechanical properties relate to the presence of Ca, Zn and Si. The basal wing-shaped structure is flexible, enabling it to interlock with the anal region during mating. The paramere is slightly twisted; the tip region is circular in cross-section, and the geometry of the rest is rather complex. In the mechanical tests, wet parameres mainly buckled, while dried parameres broke off. The level of structural failures depended on directions from which the compression forces were applied. Structural, material and mechanical strengthening mechanisms preventing the paramere from mechanical failure are discussed.

Intra-horn insemination in the alpaca Vicugna pacos: Copulatory wounding and deep sperm deposition.

Alpacas (Vicugna pacos) are reported to be the rare mammal in which the penis enters the uterus in mating. To date, however, only circumstantial evidence supports this assertion. Using female alpacas culled for meat, we determined that the alpaca penis penetrates to the very tips of the uterine horns, abrading the tract and breaking fine blood vessels. All female alpacas sacrificed one hour or 24 hours after mating showed conspicuous bleeding in the epithelium of some region of their reproductive tract, including the hymen, cervix and the tips of each uterine horn, but typically not in the vagina. Unmated females showed no evidence of conspicuous bleeding. Histological examination of mated females revealed widespread abrasion of the cervical and endometrial epithelium, injuries absent in unmated females. Within one hour of mating, sperm were already present in the oviduct. The male alpaca's cartilaginous penis tip with a hardened urethral process is likely responsible for the copulatory abrasion. The entire female reproductive tract interacts with the penis, functioning like a vagina. Alpacas are induced ovulators, and wounding may hasten delivery of the seminal ovulation-inducing factor beta-NGF into the female's blood stream. There is no evidence of sexual conflict in copulation in alpaca, and thus wounding may also be one of a variety of mechanisms devised by mammals to induce a beneficial, short-term inflammatory response that stimulates blastocyst implantation, the uterine remodeling associated with placental development, and thus the success of early pregnancy.

The relationship between duration of infertility and clinical outcomes of intrauterine insemination for younger women: a retrospective clinical study.

BACKGROUND: The objective of this research was to elucidate the association between the length of infertility and the outcomes of intrauterine insemination (IUI) in women of varying ages - a topic that has been the subject of investigation for numerous years, yet lacks a definitive consensus. METHODS: A retrospective cohort investigation involving 5268 IUI cycles was undertaken at the Reproductive Medicine Center of Nanjing Drum Tower Hospital from 2016 to 2022. Utilizing the smooth fitting curve along with threshold and saturation effect analysis, the correlation between infertility duration and IUI clinical pregnancy rates was discerned. Moreover, patients were bifurcated into two cohorts based on their respective infertility durations. A secondary examination was also performed employing propensity-score matching to mitigate the impact of confounding variables. Subsequent threshold and saturation effect analysis was carried out across various subgroups, segmented on the basis of age differentiation. RESULTS: When the duration of infertility was more than 5 years, the clinical pregnancy rate decreased with the increase of infertility duration (aOR: 0.894, 95%CI: 0.817-0.991, p = 0.043). The multivariate regression analysis suggested that longer duration of infertility (≥ 5 years) was significantly correlated with the lower clinical pregnancy rate (aOR: 0.782, 95% CI: 0.643-0.950, p = 0.01). After the propensity-score matching, the clinical pregnancy rate of women with longer infertility duration were also higher. When the duration of infertility was more than 5 years, the clinical pregnancy rate of women younger than 35 years old decreased with the increase of infertility duration (aOR: 0.906, 95%CI: 0.800-0.998, p = 0.043). CONCLUSIONS: The clinical pregnancy rate and live birth rate of IUI in young women (< 35 years old) who have been infertile for more than 5 years significantly decrease with the prolongation of infertility time. Therefore, for young women who have been infertile for more than 5 years, IUI may not be the best choice.

A single administration of carbetocin before electroejaculation increases the insemination doses produced from each ejaculate in rams.

The aim of the study was to determine the effect of carbetocin administration (a long-acting analog of oxytocin) 20 or 10 min before electroejaculation (EE) on the duration of semen collection procedure, quantitative and qualitative characteristics of the ejaculate, and stress biomarkers in rams. Semen was collected from 12 Corriedale rams (age, 2.5-5.5 years old) with EE, in a Latin-square design, administrating carbetocin (0.2 mg/100 kg of body weight i.v.) 20 or 10 min before EE, or without carbetocin administration (CB-20, CB-10, and CON treatments, respectively). Each treatment was applied to different rams every 3-4 days, allowing all the rams to receive all three treatments. Carbetocin administered 20 or 10 min before EE increased the number of sperm ejaculated (P = 0.01), the semen concentration (P = 0.02), the number of insemination doses collected in a single collection (P = 0.01), and the number of insemination doses collected/electrical pulses administered (P = 0.05) compared to control rams. Carbetocin administered 20 or 10 min before semen collection prolonged the time required for EE and the number of pulses administered during EE compared to CON rams (P < 0.03 for both). The CB-10 rams required the administration of more electrical pulses during ejaculation than CON rams (P = 0.001), and CB-20 treatment tended to require more electrical pulses than CON rams (P = 0.06). The volume of the ejaculate was greater in CB-10 than in CON rams (P = 0.01), and that of CB-20 treatment tended to be greater than CON rams (P = 0.08). The percentage of sperm with intact membrane was greater in CB-20 than in CON rams (P = 0.01). Total protein, albumin, and globulin concentrations were lower immediately after carbetocin administration 20 or 10 min before EE. The treatments did not affect cortisol concentration, glycemia, rectal and surface temperatures, heart rate, and facial expressions. Carbetocin administration before EE of rams improved the quantitative and qualitative characteristics of the ejaculate, duplicating the number of insemination doses collected. It can be a promising treatment to obtain a greater quantity of doses to inseminate with a lower frequency of semen collections, reducing the negative impacts of EE on animal welfare.

A prospective proof-of-concept trial on the effect of personalized dosages of follitropin delta in intrauterine insemination.

RESEARCH QUESTION: What is the efficacy and safety of individualized follitropin delta dosing for ovarian stimulation in intrauterine insemination (IUI)? DESIGN: This single-centre, prospective, open-label, single-cohort study involving 106 patients established an original dosing regimen based on body weight and anti-Müllerian hormone (AMH) concentrations, with adjustments based on the ovarian response from the previous IUI cycle. Each participant was enrolled in a maximum of three IUI cycles. RESULTS: Mean age was 34.5 ± 4.5 years, mean weight 69.2 ± 11.2 kg, mean AMH 15.7 ± 8.6 pmol/l, mean FSH 6.3 ± 2.6 IU/l and mean antral follicle count 16.4 ± 8.2. The percentage of patients who produced more than three mature follicles was 1.9%, 0% and 1.5%, respectively, for the three IUI cycles. The percentage of patients with two or three mature follicles was 34.0%, 36.9% and 47.1% for the three IUI cycles. The clinical pregnancy rate per IUI cycle was 17.9%, 14.3% and 17.6% for the three cycles, with a cumulative clinical pregnancy rate of 40.6%. Out of 258 cycles, 43 (16.7%) resulted in clinical pregnancy, with six of those resulting in multiple pregnancies (14.0%). Two resulted in spontaneous reduction within the first trimester and four resulted in live twin births, representing only 1.6% of the total cycles. CONCLUSIONS: This study is the first to utilize follitropin delta for stimulation in IUI. It demonstrates that individualized dosing is both effective and safe, resulting in satisfactory cumulative pregnancy rates and an acceptable multiple pregnancy rate, thus achieving the primary objectives of the research.

Time elapsed between ovulation and insemination determines the quality of fertilized rat oocytes.

Genetically modified rats are valuable models in human disease research. We recently developed an improved system for rat sperm cryopreservation and in vitro fertilization (IVF) that facilitates the efficient production and preservation of genetically modified rats. In the IVF procedure performed using frozen-thawed rat sperm, the IVF schedule is fixed to ensure timely hormone administration and oocyte collection. To enhance the flexibility of the IVF schedule, possible periods of postovulated rat oocytes with normal fertility and developmental abilities should be determined. Therefore, in this study, we examined the fertilization and developmental ability of incubated oocytes 1-13 h after oocyte collection at 9:00 AM. The fertilization rate decreased 7 h after oocyte collection, and abnormally fertilized oocytes appeared 10 h after oocyte collection. The developmental rate also decreased 7 h after oocyte collection; however, live pups were obtained from oocytes 12 h after oocyte collection. In summary, ovulated rat oocytes exhibited a high developmental ability after IVF for up to 4 h after oocyte collection.

How successful is intrauterine insemination after failed IVF? A study of 551 women.

RESEARCH QUESTION: What is the success rate of intrauterine insemination (IUI) after failing IVF? DESIGN: This retrospective cohort study evaluated the pregnancy outcomes of 551 patients who underwent a total of 992 IUI cycles at an academic fertility centre between October 2008 and April 2018. RESULTS: The study participants (n = 551) had previously failed one to three fresh IVF cycles and any resultant embryo transfers, and subsequently underwent a total of 992 IUI cycles. When comparing demographics, women with ongoing pregnancies, clinical pregnancies and positive pregnancies were significantly younger (P = 0.037, P = 0.025 and P = 0.049, respectively) compared with women who did not conceive. The cumulative ongoing pregnancy rate for all IUI cycles was 7.44% per patient (41 pregnancies in 551 patients), and the ongoing pregnancy rate after the first IUI cycle was 4.72%. In single women who had previously failed six IUI cycles before undergoing IVF cycles with donor sperm, the cumulative ongoing pregnancy rate was 15.8% in donor sperm IUI cycles compared with 5.1% in women who used their partner's sperm for both IVF and IUI cycles, with an adjusted odds ratio of 6.1. Patient age, number of previous pregnancies, daily gonadotrophin dose for IVF, number of mature follicles at trigger, and number of failed IVF cycles failed to predict pregnancy outcomes. CONCLUSION: Ongoing pregnancy following IUI after failed IVF occurs at a rate of approximately 5% per cycle, and this rate is higher if donor sperm is used for both IVF and IUI cycles. This can be considered with proper counselling in women aged <40 years, and may be discouraged in women aged ≥43 years.

Sperm replacement in sperm-storage tubules causes last-male sperm precedence in chickens.

1. This study elucidated the last-male sperm precedence (LMSP) mechanism in chickens by examining replacement in storage tubules (SSTs) after multiple artificial inseminations (AI) and the effects of seminal plasma (SP) and male breed on sperm replacement in SSTs.2. Hens were artificially inseminated with fluorescent dye-labelled spermatozoa from White Leghorn (WL) chickens. Secondary AI was conducted 3 d later with sperm labelled with different nuclear fluorescent dye. Percentage of first and second inseminated sperm in SSTs and their logarithmic odds were calculated. The effect of SP on LMSP was examined using (1) Lake's solution-washed sperm before second insemination, and (2) SP injected continuously after first insemination. Effect of breed difference on sperm replacement was investigated using Barred Plymouth Rock (BP) sperm.3. Successive WL-sperm inseminations at three-day intervals caused > 70% stored sperm replacement in SSTs. Although SP removal from sperm from second insemination significantly decreased replacement, its intra-vaginal injection did not affect release. Secondary insemination using BP sperm significantly increased replacement.4. Sperm replacement is a major factor favouring LMSP in domestic chickens. Two fluorescent staining of sperm, and intra-vaginal multiple AI technique have enabled visualisation, differentiation, and quantification of multiple inseminated sperm stored in the SSTs.

Effect of small follicles on clinical pregnancy and multiple pregnancy rates in intrauterine insemination: a cohort study.

STUDY QUESTION: What is the effect of small follicles on clinical pregnancy and multiple pregnancy rates in women undergoing IUI with ovarian stimulation (IUI-OS)? SUMMARY ANSWER: The presence of ≥2 small follicles with a diameter of 10-12 or 12-14 mm was associated with an increased chance of clinical pregnancy and the presence of any 12-14 mm or larger follicles, but not smaller follicles, was statistically significantly associated with an increased risk for multiple pregnancy. WHAT IS KNOWN ALREADY: IUI-OS is widely used as the first-line treatment for unexplained or mild male factor infertility. However, IUI is associated with the risk of multiple pregnancy. While the positive association between the number of follicles ≥14 mm and the chance of pregnancy and the risk of multiple pregnancy is known, the impact of smaller follicles is uncertain. STUDY DESIGN, SIZE, DURATION: This was a retrospective cohort study that included women undergoing IUI cycles from January 2007 to May 2021 in one assisted reproduction center. PARTICIPANTS/MATERIALS, SETTING, METHODS: We studied the impact of the number and size of follicles on trigger day on clinical pregnancy and multiple pregnancy rates. Generalized estimation equation regression models were used to compute unadjusted and adjusted odds ratios and 95% CI in all women and only women who achieved clinical pregnancy separately. The chance of clinical pregnancy and multiple pregnancy for different numbers of small follicles in cycles with one >18-mm follicle was calculated using marginal effects estimate. MAIN RESULTS AND THE ROLE OF CHANCE: This cohort included 12 933 IUI cycles in 7504 women. The overall clinical pregnancy rate was 16.1% (2081/12 933), with a multiple pregnancy rate of 10.5% (218/2081). In the adjusted analysis, the chance of clinical pregnancy increased significantly with the increase in the number of follicles with the diameter of 14-16, 16-18, and 18-20 mm. As for 10-12 mm [adjusted odds ratio (aOR) 1.22, 95% CI 1.02-1.46] and 12-14 mm (aOR 1.29, 95% CI 1.07-1.56) follicles, only groups with ≥2 follicles of those sizes showed significantly increased chance of clinical pregnancy. In cycles that led to pregnancy, follicles with the diameter of 12-14 mm were associated with an increased risk of multiple pregnancy (aOR 1.73, 95% CI 1.19-2.53 for one such follicle; aOR 2.27, 95% CI 1.44-3.56 for ≥2 such follicles), while 10- to 12-mm follicles were not significantly associated with multiple pregnancy (aOR 1.18, 95% CI 0.72-1.95 for ≥2 such follicles). The associations of multiple pregnancy were similar when including all cycles. LIMITATIONS, REASONS FOR CAUTION: This was a retrospective observational study from a single center. The records of follicle diameter in our center were of a 2-mm interval which limited our ability to analyze the size of follicle as a continuous variable. Also, the number of cycles with a high number of small follicles was still limited which impeded more detailed analysis on the ≥2 follicles subgroup. Similarly, the value of some parts of the marginal probability estimation for multiple pregnancy versus pregnancy according to size and number of follicles was also limited by the low sample size of certain combinations. WIDER IMPLICATIONS OF THE FINDINGS: Follicles larger than 10 mm, especially those ≥12 mm, may need to be clearly recorded during transvaginal ultrasound surveillance and their potential effects on both pregnancy and multiple pregnancy can be discussed with couples undergoing IUI. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (Grant numbers 82201912, 82371651, and 82071615) and Shanghai Sailing Program (21YF1423200). B.W.M. is supported by an NHMRC Investigator grant (GNT1176437). B.W.M. reports consultancy for ObsEva and Merck and travel support from Merck. B.W.M. has received research funding from Ferring and Merck. The authors declare no other competing interests. TRIAL REGISTRATION NUMBER: N/A.

Evaluation of insemination, blood feeding, and Plasmodium vivax infection effects on locomotor activity patterns of the malaria vector Anopheles darlingi (Diptera: Culicidae).

Circadian behavioral patterns in mosquitoes can be observed through their locomotor activity, which includes fundamental behaviors such as foraging, mating, and oviposition. These habits, which are fundamental to the life cycle of Anopheles mosquitoes, are closely related to pathogen transmission to humans. While rhythmic cycles of locomotor activity have been described in Anopheles species, no studies have been conducted on Anopheles darlingi species, the main malaria vector in the Amazon region. The aim of this study was to investigate how insemination status, blood meal, and Plasmodium vivax infection affect the locomotor activity of An. darlingi. The experiments were performed with 3- to 10-day-old An. darlingi females, which had been fed with 15% honey solution. These mosquitoes were obtained from the Malaria Vector Production and Infection Platform (PIVEM)/FIOCRUZ-RO. The experimental groups were divided into four categories: virgin vs. inseminated, unfed virgin vs. blood-fed virgin, unfed inseminated vs. blood-fed inseminated, and infected blood vs. uninfected blood. Locomotor activity was monitored using the Flybox equipment, capturing images that were subsequently converted into video to measure the insect activity, using PySoLo software. The periodicity and rhythmicity of mosquito locomotor activity were analyzed using MatLab® software. The locomotor activity of An. darlingi females showed a nocturnal and bimodal pattern under LD conditions. When comparing the insemination states and blood meal, there was a reduction in the locomotor activity in inseminated and blood-fed females. However, the P. vivax+ infection did not increase locomotor activity of An. darlingi species.

Effect of interval time between hysterosalpingography and intrauterine insemination on the pregnancy outcome of infertile patients.

Background: Hysterosalpingography (HSG) is the most commonly applied tubal patency test in clinical practice. Although some studies have found an increased pregnancy rate after HSG, no studies to date have specifically characterized the effect of interval time between HSG and IUI on pregnancy outcome. Objectives: To investigate the effect of interval time between HSG and intrauterine insemination (IUI) on live birth rates of infertile patients. Methods: Retrospective cohort study. The reproductive medical record system was used to identify patients who completed ≥1 IUI cycle between January 2017 and October 2021. According to the interval time between HSG and IUI, patients were divided into three groups: <6months interval group,6-12 months interval group and >12 months interval group. The generalized estimating equation with Poisson distribution was used to estimate the risk ratios (RRs) and 95% confidence intervals (CIs) of different groups. Results: A total of 413 patients completed 701 IUI cycles during the study period, <6months interval group, 415 cycles; 6-12 months interval group, 138 cycles; >12 months interval group, 148 cycles. The live birth rate of <6 months group was higher than other two groups (17.35% vs. 12.32% vs. 8.11%, P=0.017); Similarly, the clinical pregnancy rate of <6 months group was also higher than other two groups (19.76% vs. 14.49% vs.11.49%, P=0.049). When adjusted separately for FSH, AMH, infertility type, duration of infertility, infertility diagnosis, total motile count (TMC) of sperm, medications, endometrium size and dominant follicle size, the live birth rate of >12 months group severally significantly decreased by 60% (adjusted RR = 0.40, 95% CI [0.19-1.40]). The cumulative clinical pregnancy and live birth rates of <6 months group were higher than other two groups (P<0.05), but the cumulative pregnancy rate among three groups were not statistically different (log rank test: P=0.06). Conclusion: The interval time between hysterosalpingography and IUI is related to pregnancy outcome. The clinical pregnancy and live birth rates were the highest when the time interval was less than 6 months. Therefore, IUI should be recommend as soon as possible after HSG if the patient couple meets the IUI indication.

Effects of sperm separation methods before intrauterine insemination on pregnancy outcomes and live birth rates: Differences between the swim-up and microfluidic chip techniques.

Various sperm preparation techniques have been developed to obtain functionally, genetically and morphologically high-quality competent spermatozoa for use in assisted reproductive technologies, which may affect treatment options and thus pregnancy outcomes and live birth rates. We aimed to compare swim-up washing procedure (SWP) and microfluidics sperm sorting (MSS) with regard to sperm separation, pregnancy outcomes and live birth rates in infertile couples receiving intrauterine insemination. A total of 326 couples with unexplained infertility who underwent intrauterine insemination were enrolled in this retrospective cohort study and were divided into 2 groups according to sperm preparation technique. The MSS and SWP methods were used to prepare sperm in 178 and 148 patients, respectively. The median sperm concentration reduced significantly from 51 (30-100) million/mL to 20 (10-40) million/mL in the MSS group, and from 45 (26-80) million/mL to 25 (11-48) million/mL in the SWP group (both P < .001). Median motility increased significantly from 30.43 ± 17.79 to 57.48 ± 20.24 in the MSS, and from 32.89 ± 13.92 to 43.91 ± 20.11 in SWP (both P < .001). There was a difference between groups after preparation regarding sperm concentration (better with SWP) and motility (better with MSS) (P = .018 and P < .001, respectively). A total of 86 (26.4%) pregnancies were observed in participants and the clinical pregnancy rate was 23% in the MSS group and 30.4% in the SWP group (P = .133). Fifty-one infants were born alive and a great majority (n = 47) were delivered at term. Multivariate logistic regression analysis showed that higher duration of infertility was independently associated with lower live birth success (odds ratio: 0.811, 95% confidence interval: 0.662-0.996; P = .045). Other variables, including female age, type and reason of infertility, number of cycles, and sperm motility and concentration, were found to be nonsignificant (P > .05). We observed nonsignificant worse reproductive results using microfluid sperm selection in comparison to the pellet swim-up technique (live birth rate = 12% vs 20%). Our evidence is of limited quality due to the retrospective design of this study and sufficiently powered RCTs are needed to evaluate whether sperm selection based using a microfluidic chip is better, similar, or worse than the pellet swim-up technique.

The effects of female age on blood-feeding, insemination, sperm storage, and fertility in the dengue vector mosquito Aedes aegypti (Diptera: Culicidae).

Mating induces behavioral and physiological changes in female insects-collectively referred to as the female post-mating response (PMR)-that facilitate the production of progeny. PMRs are elicited by transfer of male-derived seminal components during mating, but are altered by other factors, including adult age. Increased female age is often accompanied by declines in fertility. However, mating shortly after emergence also impacts fertility in the insect model Drosophila melanogaster. Here, we determined the age post-emergence when females of the vector mosquito Aedes aegypti can be inseminated and blood-feed. We next examined fecundity, fertility, and the storage of sperm in the female reproductive tract in "young" (30-41 hours-old) and "old" (2- and 3-week-old) females, finding that blood-feeding began at 14 hours, and mating at ∼24 hours post-emergence. Although young females consumed smaller blood quantities and stored fewer sperm, they were similarly fertile to 4-day-old controls. Old females, however, suffered significant declines in fecundity by 2 weeks of age. Our results show that female Ae. aegypti start to become sexually receptive 1 day after their emergence, but can ingest blood much sooner, suggesting that mating is not a prerequisite to blood-feeding, and that females can ingest an arbovirus infected blood-meal shortly after emergence.

Queen quality, performance, and winter survival of imported and domestic honey bee queen stocks.

Canadian beekeepers have faced high colony mortality each winter over the last decade. Frequently citing "poor queen quality" as a top contributing factor to colony loss, Canadian beekeepers report needing to replace half their queens each year. Domestic queen production exists throughout Canada but is limited due to the short season and can be further limited when colony mortality is high. Consequently, Canadian beekeepers import over 260,000 queens annually, primarily from locations with warmer climates. In this study, newly mated imported queens from Hawaii (USA) and New Zealand were compared to domestic Canadian queens produced in British Columbia; these stocks were evaluated on their morphological and sperm storage characteristics. Stock quality was also evaluated in the field at two locations in Alberta, Canada over two production seasons. Our results show initial variation in queen morphology and fertility among imported and domestic queen stocks. Most striking, the New Zealand queens weighed 10-13% less than the Hawaii and British Columbia queens, respectively upon arrival. Colony performance over a two-year field study suggests: (1) brood pattern solidness has a positive nonlinear correlation with honey production regardless of queen stock and environment; (2) environment (i.e., apiary location) and queen stock variably predict colony health and productivity depending on year; specifically, apiary site appears to be a stronger predictor of colony health and productivity than queen stock in year one, but in year two, queen stock appears to be a stronger predictor than apiary site; (3) high clinical symptoms of chalkbrood may explain the prevalence of poor brood patterns in colonies headed by queens from New Zealand; (4) domestic queens are 25% more likely to survive winter in Alberta than imported queens. Therefore, it is important to consider possible mismatches in disease immunity and climate conditioning of imported queen stocks heading colonies in temperate regions that face drastically different seasonal climates and disease ecology dynamics.

Pregnancy outcomes of intrauterine insemination in young patients with diminished ovarian reserve: a multicenter cohort study.

BACKGROUND: To date, there is no consensus on whether intrauterine insemination (IUI) treatment is required in young patients with diminished ovarian reserve (DOR). Pregnancy outcomes in young DOR patients undergoing IUI are controversial. The existing studies are all single-center studies, with no existing multicenter cohort studies. The purpose of this multicenter study was to investigate the pregnancy outcomes of young DOR patients undergoing IUI. METHODS: This multicenter cohort study included a total of 4600 cycles in 2204 infertile patients who underwent IUI treatment in three reproductive medical centers between September 2018 and January 2022. The research subjects were divided into two groups according to their serum anti-Müllerian hormone (AMH) levels. Propensity score matching (PSM) was used to match the research subjects at a ratio of 1:4. The pregnancy outcomes in the two groups were compared. RESULTS: There was no significant difference in the clinical pregnancy rates (CPR), biochemical rates, and ectopic pregnancy rates between the two groups (P > 0.05). There were, however, significant differences in the miscarriage rates between the groups (P < 0.05). The live birth rates (LBR) were 6.6 vs. 9.9 between the two groups. The multivariable logistic regression models reveal that body mass index, AMH were significantly correlated with CPR; AMH were significantly correlated with LBR; BMI, follicle stimulating hormone were significantly correlated with miscarriage rate. CONCLUSIONS: The clinical pregnancy rate of DOR patients was not significantly different from that of NOR patients; however, the miscarriage rates were significantly different from those of NOR patients.