Low Birth Rate Research Articles

Diabetes, life course and childhood socioeconomic conditions: an empirical assessment for Mexico

BackgroundDemographic and epidemiological dynamics characterized by lower fertility rates and longer life expectancy, as well as higher prevalence of non-communicable diseases such as diabetes, represent important challenges for policy makers around the World. We investigate the risk factors that influence the diagnosis of diabetes in the Mexican population aged 50 years and over, including childhood poverty.ResultsThis work employs a probabilistic regression model with information from the Mexican Health and Aging Study (MHAS) of 2012 and 2018. Our results are consistent with the existing literature and should raise strong concerns. The findings suggest that risk factors that favor the diagnosis of diabetes in adulthood are: age, family antecedents of diabetes, obesity, and socioeconomic conditions during both adulthood and childhood.ConclusionsPoverty conditions before the age 10, with inter-temporal poverty implications, are associated with a higher probability of being diagnosed with diabetes when older and pose extraordinary policy challenges.

The reproductive journeys of French women over 40 seeking assisted reproductive technology treatments in Spain

Fertility decline is a complex phenomenon resulting from converging social and cultural changes that are governed through politics. As it has been discussed in many studies, the European's low fertility rate goes hand in hand with the trend of maternity postponement. Although in many European countries over the last decades reproduction is envisaged as an individual choice that can be made at older ages, having a child after a certain age can be impossible -either “naturally” or using assisted reproductive technology-depending on the medical and legislative possibilities and limits of the country in which people live. In the extremely diverse European reproscape, reproductive legislations have forced but also allowed many people to seek reproductive treatments outside their home countries.Spain is a leading destination in Europe for cross border reproductive travel and, of the foreigners it receives, the French are the largest group. Despite having a history of strong pro-natalist policies, France has been one of the strictest European countries regarding access to medically assisted procreation. Until 2022, only heterosexual couples in which women were under 43 years of age could access treatments. Despite the recent opening of access to “all women”, including single women and same-sex female couples, women over 43 years of age were once again excluded from the new legal framework and therefore remain condemned to travel abroad to access reproductive treatments. In this article, we analyze the experience of French women over 40 who cross the Spanish border to access reproductive treatments in order to fulfill their desire to have children. Through ethnographic data emerging from six years of participant observation and in-depth interviews with 15 women, we explore why they remain excluded from the French system of reproductive governance and the obstacles they face during their reproductive journey.

Analysis of Assisted Reproductive Technology Treatment of 126 Uterine Adenomyosis Patients Diagnosed via Ultrasonography

Background: Uterine Adenomyosis (Ut-Ad) is a condition in which the endometrial glands and stroma invade extensively into the uterine myometrium, causing the uterus to enlarge and leading to treatment-resistant infertility. In this study, we diagnosed Ut-Ad in the absence of concomitant ovarian endometriosis using ultrasound and conducted assisted reproductive technology (ART) on 126 patients desiring pregnancy. We report our clinical outcomes and discuss potential future treatments. Methods: Ut-Ad was diagnosed independently, without concurrent external endometriosis. We retrospectively analyzed the clinical pregnancy, live birth, and miscarriage rates of 126 patients with Ut-Ad who underwent ART at our clinic, comparing them with 2,472 non-Ut-Ad individuals as controls. Additionally, we examined CA-125 levels and assessed the severity of dysmenorrhea. Results: The Ut-Ad group exhibited significantly lower pregnancy and live birth rates, along with lower gestational age and birth weight, compared to the non-Ut-Ad group. However, embryonic development until embryo transfer was comparable between the Ut-Ad and non-Ut-Ad groups. Notably, the miscarriage rate in the Ut-Ad group was significantly higher than that in the control group. Conclusions: Historically, clinical outcomes for Ut-Ad have been suboptimal, even with the use of modern ART treatments, resulting in low pregnancy rates. While the exact cause of Ut-Ad remains elusive, recent ultrasound findings suggest that minor disruptions in the uterine endometrium may contribute to adenomyosis development in young women with symptoms. Continuous monitoring via transvaginal ultrasound could facilitate early diagnosis and treatment, potentially offering substantial benefits for Ut-Ad management in the future.

Trade-off between double cleavage-stage embryos transfer and single blastocyst-stage embryo transfer in patients with few good quality embryos in antagonist cycles: a retrospective study using a propensity score matching analysis

ObjectiveThis study aimed to compare the per OPU clinical outcomes for transfer of Day 3 double cleavage-stage embryos (DET) and Day 5 single blastocyst-stage (SBT) in patients with five or fewer good quality embryos on day 3 per occyte pick-up cycle (OPU) in antagonist cycles with consideration of blastocyst formation failure.MethodsThis was a retrospective, observational cohort study of 2,116 cases of OPU treated with antagonist protocol in the affiliated Chenggong Hospital of Xiamen University between January 2013 and December 2020. DET was performed in 1,811cycles and SBT was performed in 305 cycles. The DET group was matched to the SBT group by propensity score (PS) matching according to multiple maternal baseline covariates. After PS matching, there were 303 ET cycles in each group. The primary outcomes were the cumulative live birth rate (CLBR), cumulative multiple pregnancy rate(CMPR)per OPU and the number of ET to achieve live birth per OPU. Secondary outcomes were the percentage of clinical pregnancy(CPR), live birth rate(LBR), multiple pregnancy rate(MPR).ResultsFollowing PS mating, the CLBR was slightly higher (48.8% versus 40.3% ; P = 0.041) and the CMPR was significantly higher in the DET group compared to SBT group(44.2% versus 7.9%, P < 0.001). The CPR, LBR and MPR per fresh transfer were higher in DET group compared to SBT group(50.2% versus 28.7%; 41.3% versus 21.5%;29.6% versus 0%, P < 0.001). The number of ET to achieve live birth per OPU in SBT group was obiviously more than in DET group(1.48 ± 0.578 versus 1.22 ± 0.557 ,P < 0.001).ConclusionWith a marginal difference cumulative live birth rate, the lower live birth rate per fresh transfer and higher number of ET per OPU in the SBT group suggested that it might take longer time to achieve a live birth with single blastocyst strategy. A trade-off decision should be made between efficiency and safety.

Social determinants of health that impact the time to diagnosis and treatment of infertility in Taiwan.

Taiwan is one of the countries with the lowest birth rate in the world. We investigated factors associated with the time to diagnosis and treatment of infertility in Taiwan. The study was conducted through an online questionnaire in December 2021. The questionnaire was adapted from a previously published multinational survey, and culture-specific questions were added. 91 infertile patients and 89 partners of patients in Taiwan, aged 20- to 45- year-old, were included. The average duration before diagnosis was 2.9 years, followed by 1.5 years before treatment. Older age at marriage (p=0.0024), higher education level (P=0.0001), and a higher gender equality score (p=0.0031) were associated with earlier diagnosis. Conversely, folk therapy use was linked to later diagnosis (p<0.0001) and treatment (p<0.0001). Notably, in the female (p=0.039) and patient (p=0.0377) subgroups, a higher gender equality score was associated with a shorter duration of folk therapy. Subjectively, the most frequent factor influencing treatment decision was affordability or lack thereof. The government subsidy for in vitro fertilization led to increased treatment willingness for 46.3% of respondents, and 47.3% reported more likely to pursue earlier treatment. This study highlights the influence of education, gender equality, folk therapy, and government subsidy on fertility care decisions. To improve the timeliness of infertility healthcare in Taiwan, potential strategies include promoting education, fostering gender equality, providing financial support, and raising awareness on the association between folk therapy and delayed medical care.

Population density effects on gamete traits and fertilisation dynamics under varying sperm environments in mussels.

Gamete traits can vary widely among species, populations and individuals, influencing fertilisation dynamics and overall reproductive fitness. Sexual selection can play an important role in determining the evolution of gamete traits with local environmental conditions determining the strength and direction of sexual selection. Here, we test for signatures of post-mating selection on gamete traits in relation to population density, and possible interactive effects of population density and sperm concentration on sperm motility and fertilisation rates among natural populations of mussels. Our study shows that males from high-density populations produce smaller sperm compared with males from low-density populations, but we detected no effect of population density on egg size. Our results also reveal that females from low-density populations tended to exhibit lower fertilisation rates across a range of sperm concentrations, although this became less important as sperm concentration increased. Variances in fertilisation success were higher for females than males and the effect of gamete compatibility between males and females increases as sperm concentrations increase. These results suggest that local population density can influence gamete traits and fertilisation dynamics but also highlight the importance of phenotypic plasticity in governing sperm-egg interactions in a highly dynamic selective environment.

The Effect of Open and Closed Oocyte Vitrification Systems on Embryo Development: A Systematic Review and Network Meta-Analysis.

Background/Objectives: Open and closed vitrification systems are commonly employed in oocyte cryopreservation; however, there is limited evidence regarding a comparison of their separate impact on oocyte competence. This study uniquely brings to the literature, data on the effect of open versus closed vitrification systems on laboratory and clinical outcomes, and the effect of cooling and warming rates. Methods: A systematic search of the literature was performed using the databases PubMed/MEDLINE and the Cochrane Central Library, limited to articles published in English up to January 2023. A network meta-analysis was conducted comparing each vitrification system versus fresh oocytes. Results: Twenty-three studies were included. When compared to fresh oocytes, both vitrification devices resulted in lower fertilization rates per MII oocyte retrieved. When comparing the two systems in terms of survival rates, no statistically significant difference was observed. However, interestingly open systems resulted in lower cleavage and blastocyst formation rates per 2 pronuclear (2PN) oocyte compared to fresh controls, while at the same time no statistically significant difference was detected when comparing closed devices with fresh oocytes. Conclusions: In conclusion, closed vitrification systems appear to exert a less detrimental impact on the oocytes' competence, which is reflected in the blastocyst formation rates. Proof of superiority of one system versus the other may lead to standardization, helping to ultimately determine optimal practice in oocyte vitrification.

Soybean (Glycine max (L.) Merr.) response to application of mineral nitrogen and bradyrhizobia on Nitisols of Teppi, Southwest Ethiopia

Soybean (Glycine max (L.) Merr.), an important crop grown for its protein source for humans and livestock, is widely introduced in different parts of Ethiopia. However, the productivity of the crop is far below its potential in the country due to different factors, among which low soil fertility is a major contributor. Hence, this field experiment was conducted with the objective of determining the optimum rate of starter nitrogen (N) and bradyrhizobium inoculation on yield and yield components of soybean in the 2019 and 2020 cropping seasons. Two levels of bradyrhizobia (inoculated and uninoculated) and six levels of starter nitrogen (0, 9, 18, 27, 36, and 54 kg N ha−1) were arranged in a factorial design. The result showed that soybean grain yield increased by about 60 % with inoculation of bradyrhizobia applied with low rates of starter nitrogen fertilizer, regardless of cropping seasons. Application of a nitrogen rate above 18 kg N ha−1 leads to yield decline and has no significant variation from bradyrhizobia inoculation only. Regardless of the cropping seasons, elevated levels of starter nitrogen beyond 27 kg ha−1 suppressed nodulation and nodule dry matter. Starter N at a rate of 9 and 18 kg N ha−1 improved soybean nodulation by 125–130 % over control and 95 % over bradyrhizobia inoculation alone. Thus, it was recommended to apply bradyrhizobia strains with 9 or 18 kg N ha−1 starter nitrogen for better yield of soybean as well as adequate nitrogen fixation in Nitisols having moderate soil nitrogen levels similar to the Teppi areas.

PERIODISATION OF CHANGES IN STATE FAMILY POLICY IN POLAND BETWEEN 1989 AND 2022

The subject of this article is the periodization of changes in the state family policy in Poland that took place in the years 1989–2022, in order to systematize on this basis the main directions, priorities and instruments of the title policy as well as the most significant events, activities and turning points in a given area. This analysis shows a multi-aspect perspective on the assessment of the evolution of family policy in Poland in the years 1989–2022. Indicates, among others: periods in which there was a significant expansion of the scope of state intervention in the functioning of the family, especially through a significant increase in expenditure on financial instruments, for example after 2015. However, the development of service and leave instruments is particularly important, which took place in particular in 2013 as part of the "Good climate for the family" program. Due to the low fertility rate, financial difficulties of many families and difficulties in combining child care responsibilities with paid work, family policy should be based to a greater extent on investments and social services.

Diverse impacts of female chromosomal polymorphisms on assisted reproduction outcomes: a retrospective cohort study

BackgroundThe effects of female chromosomal polymorphisms (FCPs) on various aspects of reproductive health have been investigated, yet the findings are frequently inconsistent. This study aims to clarify the role of FCPs on the outcomes of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).MethodsThis retrospective cohort study comprised 951 couples with FCPs and 10,788 couples with normal karyotypes who underwent IVF/ICSI treatment at Peking University Third Hospital between 2015 and 2021. The exposure was FCPs. The embryological outcomes and clinical outcomes were compared.ResultsThe FCPs, as a whole, compromised the oocyte maturation rate (76.0% vs. 78.8%, P = 0.008), while they did not adversely affect other IVF/ICSI outcomes. Further detailed analyses showed that every type of FCPs contributed to the lower oocyte maturation rate, particularly the rare FCPs (69.0% vs. 78.8%, P = 0.008). The female qh + was associated with a higher normal fertilization rate (63.0% vs. 59.2%, adjusted P = 0.022), a higher clinical pregnancy rate (37.0% vs. 30.7%, adjusted P = 0.048), and a higher live birth rate (27.0% vs.19.0%, adjusted P = 0.003) in couples undergoing IVF. Conversely, in couples undergoing ICSI, female qh + was found to be related to a lower normal fertilization rate (58.8% vs. 63.8%, P = 0.032), a comparable clinical pregnancy rate (25.7% vs. 30.9%, P = 0.289), and a comparable live birth rate (19.8% vs. 19.2%, P = 0.880) compared to the control group. Additionally, an increased risk of preterm birth was observed in women undergoing IVF with multiple polymorphisms (62.5% vs. 16.9%, adjusted P <  0.001) and in women undergoing ICSI with pstk+ (36.4% vs. 15.4%, P = 0.036).ConclusionsOur research unravels the diverse impacts of various FCPs on IVF/ICSI outcomes, highlighting the detrimental effects of FCPs on oocyte maturation and the risk of preterm birth.

The ‘demographic winter’ in Italy: Crisis factors, problematic issues and policy actions

Demographic issues are becoming key to the debate on the future of Europe, and of Italy in particular, which has the lowest birth rate in Europe but is among the top-ranked countries for demographic ageing. The general improvement of living conditions and the ageing of large cohorts cannot be supported by the economic activity of the younger generations, which calls into question the security of certain aspects of the social pact, such as the provision of pensions and health care. While encouraging an awareness among Italians of the trends and problems they will have to deal with, all national actors must cooperate to ensure the recovery of the birth rate, and to harness the economic benefits of incoming migrants and the experiences of older people. It is equally necessary to meet the needs of young people and enhance their social role. Only through such cooperation will it be possible to create a favourable climate for actions that will allow us to control and direct these demographic phenomena and not to suffer from them.

The allostery and modification of hGHRH molecules and specific dimer produced significant fertility effect by proliferating and activating in-situ ovarian mesenchymal stem cells

The negative coordination of growth hormone secretagogue receptor (GHS-R) and growth hormone-releasing hormone receptor (GHRH-R) involves in the repair processes of cellular injury. The allosteric U- or H-like modified GHRH dimer Grinodin and 2Y were comparatively evaluated in normal Kunming mice and hamster infertility models induced by CPA treatment. 1–3–9 µg of Grinodin or 2Y per hamster stem-cell-exhaustion model was subcutaneously administered once a week, respectively inducing 75–69–46 or 45–13–50 % of birth rates. In comparison, the similar mole of human menopausal gonadotropin (hMG) or human growth hormone (hGH) was administered once a day but caused just 25 or 20 % of birth rates. Grinodin induced more big ovarian follicles and corpora lutea than 2Y, hMG, hGH. The hMG-treated group was observed many distorted interstitial cells and more connective tissues and the hGH-treated group had few ovarian follicles. 2Y had a plasma lifetime of 21 days and higher GH release in mice, inducing lower birth rate and stronger individual specificity in reproduction as well as only promoting the proliferation of mesenchymal-stem-cells (MSCs) in the models. In comparison, Grinodin had a plasma lifetime of 30 days and much lower GH release in mice. It significantly promoted the proliferation and activation of ovarian MSCs together with the development of follicles in the models by increasing Ki67 and GHS-R expressions, and decreasing GHRH-R expression in a dose-dependent manner. However, the high GH and excessive estrogen levels in the models showed a dose-dependent reduction in fertility. Therefore, unlike 2Y, the low dose of Grinodin specifically shows low GHS-R and high GHRH-R expressions thus evades GH and estrogen release and improves functions of organs, resulting in an increase of fertility.

Research on the Low Fertility Rate in China

Research on the Low Fertility Rate in China

Retrospective Cohort Study on the Impact of the COVID-19 Pandemic on Pregnancy Outcomes for Women Living With HIV in British Columbia.

For pregnant women living with HIV (WLWH), engagement in care is crucial to maternal health and reducing the risk of perinatal transmission. To date, there have been no studies in Canada examining the impact of the COVID-19 pandemic on pregnant WLWH. This was a retrospective cohort study assessing the impact of the pandemic on perinatal outcomes for pregnant WLWH using data from the Perinatal HIV Surveillance Program in British Columbia, Canada. We compared maternal characteristics, pregnancy outcomes, and clinical indicators related to engagement with care between a prepandemic (January 2017-March 2020) and pandemic cohort (March 2020-December 2022). We investigated preterm birth rates with explanatory variables using logistic regression analysis. The prepandemic cohort (n = 87) had a significantly (P < 0.05) lower gestational age at the first antenatal encounter (9.0 vs 11.8) and lower rates of preterm births compared with the pandemic cohort (n = 56; 15% vs 37%). Adjusted odds of preterm birth increased with the presence of substance use in pregnancy (aOR = 10.45, 95% confidence interval: 2.19 to 49.94) in WLWH. There were 2 cases of perinatal transmission of HIV in the pandemic cohort, whereas the prepandemic cohort had none. The pandemic had pronounced effects on pregnant WLWH and their infants in British Columbia including higher rates of preterm birth and higher gestational age at the first antenatal encounter. The nonstatistically significant increase in perinatal transmission rates is of high clinical importance.

Hysterosalpingo-foam sonography versus hysterosalpingography during fertility work-up: an economic evaluation alongside a randomized controlled trial.

What are the costs and effects of tubal patency testing by hysterosalpingo-foam sonography (HyFoSy) compared to hysterosalpingography (HSG) in infertile women during the fertility work-up? During the fertility work-up, clinical management based on the test results of HyFoSy leads to slightly lower, though not statistically significant, live birth rates, at lower costs, compared to management based on HSG results. Traditionally, tubal patency testing during the fertility work-up is performed by HSG. The FOAM trial, formally a non-inferiority study, showed that management decisions based on the results of HyFoSy resulted in a comparable live birth rate at 12 months compared to HSG (46% versus 47%; difference -1.2%, 95% CI: -3.4% to 1.5%; P = 0.27). Compared to HSG, HyFoSy is associated with significantly less pain, it lacks ionizing radiation and exposure to iodinated contrast medium. Moreover, HyFoSy can be performed by a gynaecologist during a one-stop fertility work-up. To our knowledge, the costs of both strategies have never been compared. We performed an economic evaluation alongside the FOAM trial, a randomized multicenter study conducted in the Netherlands. Participating infertile women underwent, both HyFoSy and HSG, in a randomized order. The results of both tests were compared and women with discordant test results were randomly allocated to management based on the results of one of the tests. The follow-up period was twelve months. We studied 1160 infertile women (18-41 years) scheduled for tubal patency testing. The primary outcome was ongoing pregnancy leading to live birth. The economic evaluation compared costs and effects of management based on either test within 12 months. We calculated incremental cost-effectiveness ratios (ICERs): the difference in total costs and chance of live birth. Data were analyzed using the intention to treat principle. Between May 2015 and January 2019, 1026 of the 1160 women underwent both tubal tests and had data available: 747 women with concordant results (48% live births), 136 with inconclusive results (40% live births), and 143 with discordant results (41% had a live birth after management based on HyFoSy results versus 49% with live birth after management based on HSG results). When comparing the two strategies-management based on HyfoSy results versus HSG results-the estimated chance of live birth was 46% after HyFoSy versus 47% after HSG (difference -1.2%; 95% CI: -3.4% to 1.5%). For the procedures itself, HyFoSy cost €136 and HSG €280. When costs of additional fertility treatments were incorporated, the mean total costs per couple were €3307 for the HyFoSy strategy and €3427 for the HSG strategy (mean difference €-119; 95% CI: €-125 to €-114). So, while HyFoSy led to lower costs per couple, live birth rates were also slightly lower. The ICER was €10 042, meaning that by using HyFoSy instead of HSG we would save €10 042 per each additional live birth lost. When interpreting the results of this study, it needs to be considered that there was a considerable uncertainty around the ICER, and that the direct fertility enhancing effect of both tubal patency tests was not incorporated as women underwent both tubal patency tests in this study. Compared to clinical management based on HSG results, management guided by HyFoSy leads to slightly lower live birth rates (though not statistically significant) at lower costs, less pain, without ionizing radiation and iodinated contrast exposure. Further research on the comparison of the direct fertility-enhancing effect of both tubal patency tests is needed. FOAM trial was an investigator-initiated study, funded by ZonMw, a Dutch organization for Health Research and Development (project number 837001504). IQ Medical Ventures provided the ExEm®-FOAM kits free of charge. The funders had no role in study design, collection, analysis, and interpretation of the data. K.D. reports travel-and speakers fees from Guerbet and her department received research grants from Guerbet outside the submitted work. H.R.V. received consulting-and travel fee from Ferring. A.M.v.P. reports received consulting fee from DEKRA and fee for an expert meeting from Ferring, both outside the submitted work. C.H.d.K. received travel fee from Merck. F.J.M.B. received a grant from Merck and speakers fee from Besins Healthcare. F.J.M.B. is a member of the advisory board of Merck and Ferring. J.v.D. reported speakers fee from Ferring. J.S. reports a research agreement with Takeda and consultancy for Sanofi on MR of motility outside the submitted work. M.v.W. received a travel grant from Oxford Press in the role of deputy editor for Human Reproduction and participates in a DSMB as independent methodologist in obstetrics studies in which she has no other role. B.W.M. received an investigator grant from NHMRC GNT1176437. B.W.M. reports consultancy for ObsEva, Merck, Guerbet, iGenomix, and Merck KGaA and travel support from Merck KGaA. V.M. received research grants from Guerbet, Merck, and Ferring and travel and speakers fees from Guerbet. The other authors do not report conflicts of interest. International Clinical Trials Registry Platform No. NTR4746.

The responsibility and action of corporations for the development of 0-3 years old children’s childcare services in China

ABSTRACT This paper discusses the necessity of promoting national childcare development and establishing corporation childcare within the context of China’s low fertility rate. It emphasizes the significance of traditional Chinese cultural values as foundational elements for promoting corporation childcare initiatives and their growth. It examines the evolving responsibilities of corporations in China’s childcare development amidst varying government policies over time. Given the increasing innovation and responsibility among Chinese corporations. the article categorizes three modes of corporation childcare based on current trends: corporation self-built childcare, collaborative childcare with third parties, and embedded childcare. It advocates for customized childcare services, nurturing the happiness of children, fostering parent-child interactions, building childcare brands, and creating a conducive business environment tailored to each mode. Building these modes, the paper offers recommendations across five dimensions: customizing childcare services, supporting the joyful upbringing of young children, promoting parent-child interaction, branding childcare facilities, fostering a conducive business environment, aiming to establish a comprehensive corporation childcare network. Lastly, the paper explores future development prospects, focusing on promoting the expansion driven by corporation childcare, addressing homogenization among corporation childcare facilities, considering the integration of elderly and childcare to leverage the experience of the elderly and fulfill social responsibilities in elder care.

When massified higher education meets shrinking birth rates: the case of South Korea

AbstractMost discussions of higher education research in the last four decades have focused on expanding higher education, including increasing access, equity, and quality. However, the growth of higher education enrolment has slowed in many advanced higher education systems since the achievement of massification, with enrolment declining more dramatically in some systems than in others. South Korea (hereafter Korea), which has experienced one of the most dynamic evolutions in higher education, was recently reported to have the lowest birth rate among OECD countries, and its drastic demographic changes are significantly affecting all aspects of higher education. This paper describes Korea’s shrinking youth population and its impact on different stakeholders in Korean higher education. It also reviews and evaluates Korea’s policies in reaction to the declining population in higher education. The findings of this paper provide policy implications for countries that will experience similar challenges associated with declining enrolment in the years to come, including institutional closures, mergers, and strategies to maintain competitiveness.

Impacts of male chromosomal polymorphisms on semen quality and IVF/ICSI outcomes: A retrospective cohort study.

The study aims to elucidate the impacts of different types of male chromosomal polymorphisms (MCPs) on various outcomes of invitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment. This retrospective cohort study included 1442 couples with normal karyotypes, 1442 couples with MCPs, 42 couples with male chromosomal rearrangements (MCRs), and 42 couples with MCRs combined with MCPs who underwent IVF/ICSI treatment at Peking University Third Hospital from 2015 to 2021. The semen quality, embryological outcomes, and clinical outcomes of different groups stratified by karyotypes were compared. For couples undergoing IVF, male inv(9) was associated with a significantly lower sperm viability rate (29.41% vs 34.49%, P = 0.030), a lower progressive motility rate (25.13% vs 30.50%, P = 0.013), and a lower normal fertilization rate (52.41% vs 59.84%, P = 0.014). Male 9qh + was related to a lower sperm viability rate (27.56% vs 34.49%, P = 0.028). No MCPs were observed to compromise clinical outcomes in couples undergoing IVF. For couples undergoing ICSI, no MCPs exhibited an association with poorer semen quality and embryological outcomes. However, Yqh + and DGpstk+ were found to be significantly correlated with an increased likelihood of preterm birth (23.3% vs 9.2%, P = 0.003; 20.0% vs 9.2%, P = 0.041, respectively). In couples with MCRs, the presence of MCPs significantly reduced the sperm viability rate (19.99% vs 30.97%, P = 0.017) and progressive motility rate (8.07% vs 27.85%, P = 0.018). Our study provides detailed evidence for the impacts of various MCPs on IVF/ICSI outcomes, reveals the complexity and heterogeneity of these impacts, and highlights the adverse effects of male inv(9).

Multivariate analyses on male factors and construction of a nomogram for predicting low in vitro fertilization rate

Low fertilization rate (LFR) and total fertilization failure (TFF) are often encountered in routine in vitro fertilization (IVF) procedure. To solve this problem, multivariate analyses on the relationship between male factors and in vitro fertilization rate were performed, and a nomogram for prediction of LFR was constructed. This retrospective study contained 2011 couples who received IVF treatment from January 2017 to December 2021. Man factors and in vitro fertilization rate were collected. Among these couples, 1347 cases had in vitro fertilization rates ≥30 % (control group), and 664 cases had in vitro fertilization rates <30 % (LFR group). Univariate analyses of male factors found that between the two groups there were significant differences (p < 0.05) in sperm progressive motility (SPR), sperm concentration (SC), total sperm number, normal sperm morphology rate (NSMR), DNA fragmentation index (DFI), sperm acrosin activity (SAA) and the clinical diagnosis of primary or secondary infertility. Multivariate logistic regression analyses showed that SPR, SAA, and SC were independent risk factors for LFR. An algorithm and a correspondent nomogram for predicting high LFR risk were constructed using data from the training cohort. The LFR nomogram exhibited an excellent discrimination power and a high fitting degree in both the training cohort (AUC = 0.90, 95 % CI: 0.88–0.92), (H-L: x2 = 5.43, p = 0.71) and validation cohort (AUC = 0.89, 95 % CI:0.87–0.92), (H-L: x2 = 7.85, p = 0.45), respectively. The decision curve analysis (DCA) demonstrated a high efficiency of the LFR nomogram for clinical utility. SPR, SAA, and SC are independent risk factors for LFR. The LFR nomogram established based on these factors could be a useful tool to predict high risk of LFR, and patients with high risk of LFR can be guided to direct ICSI procedure. Clinical application of the LFR nomogram may increase the in vitro fertilization rate by facilitating the decision making in IVF service.

Return Migration and Fertility: French Overseas Emigrants, Returnees, and Nonmigrants at Origin and Destination.

Although growing research has emphasized the critical importance of studying returns for understanding various aspects of migration processes, knowledge regarding return migrants' fertility behaviors remains limited. This study addresses this knowledge gap by comparing rates of first births and completed fertility among three groups: nonmigrants (at origin), migrants, and return migrants. Using extensive data collected both in the home regions and at destination, we analyze female migration from Martinique, Guadeloupe, French Guiana, and Réunion Island to metropolitan France (European France). We find intermediate fertility behaviors for return migrants relative to nonmigrants and migrants: on average, completed fertility levels are lower among return migrants than nonmigrants but slightly higher among return migrants than migrants. Some of these differences can be attributed to selection into migration and return, although significant gaps persist among women with similar socioeconomic characteristics. Our findings highlight three key observations. First, when migrants return before beginning childbearing, their transition to motherhood closely resembles that of nonmigrants with similar characteristics. Second, the lower fertility rates among prospective return migrants indicate an anticipation of disruption effects. Finally, reduced fertility while residing in metropolitan France translates into lower completed fertility rates for return migrants.