As the most abundant small RNAs, piwi-interacting RNAs (piRNAs) have been identified as a new class of non-coding RNAs with 24-32 nucleotides in length, and they are expressed at high levels in male germ cells. PiRNAs have been implicated in the regulation of several biological processes, including cell differentiation, development, and male reproduction. In this review, we focused on the functions and molecular mechanisms of piRNAs in controlling spermatogenesis, including genome stability, regulation of gene expression, and male germ cell development. The piRNA pathways include two major pathways, namely the pre-pachytene piRNA pathway and the pachytene piRNA pathway. In the pre-pachytene stage, piRNAs are involved in chromosome remodeling and gene expression regulation to maintain genome stability by inhibiting transposon activity. In the pachytene stage, piRNAs mediate the development of male germ cells via regulating gene expression by binding to mRNA and RNA cleavage. We further discussed the correlations between the abnormalities of piRNAs and male infertility and the prospective of piRNAs\' applications in reproductive medicine and future studies. This review provides novel insights into mechanisms underlying mammalian spermatogenesis and offers new targets for diagnosing and treating male infertility.

Infertility is a rising global health issue with a far-reaching impact on the socioeconomic livelihoods. As there are highly complex causes of male and female infertility, it is highly desired to promote and maintain reproductive health by the integration of advanced technologies. Biomedical engineering, a mature technology applied in the fields of biology and health care, has emerged as a powerful tool in the diagnosis and treatment of infertility. Nowadays, various promising biomedical engineering approaches are under investigation to address human infertility. Biomedical engineering approaches can not only improve our fundamental understanding of sperm and follicle development in bioengineered devices combined with microfabrication, biomaterials, and relevant cells, but also be applied to repair uterine, ovary, and cervicovaginal tissues and restore tissue function. Here, we introduce the infertility in male and female and provide a comprehensive summary of the various promising biomedical engineering technologies and their applications in reproductive medicine. Also, the challenges and prospects of biomedical engineering technologies for clinical transformation are discussed. We believe that this review will promote communications between engineers, biologists, and clinicians and potentially contribute to the clinical transformation of these innovative research works in the immediate future.

OBJECTIVE: This paper uses health economics methods to discuss the cost-effectiveness value of long protocol and antagonist protocol for in vitro fertilisation and embryo transfer (ET) in the Chinese population.
METHODS: Health economic evaluation study.
METHODS: The data needed to construct the model for this study were derived from published studies and other secondary sources in China.
METHODS: No patients participated in the study.
METHODS: The main outcomes were live birth rate (LBR) and cost. From the societal perspective, we considered the direct and indirect costs over the course of the treatment cycles. A cost-effectiveness was measured using the incremental cost-effectiveness ratio and the probability that a protocol has higher net monetary benefit. Sensitivity analysis was carried out to verify the reliability of the simulation results.
RESULTS: For the Chinese population, the long protocol resulted in a higher LBR than the antagonist protocol (29.33% vs 20.39%), but at the same time, it was more expensive (￥29 146.26 (US$4333.17) vs ￥23 343.70 (US$3470.51)), in the case of considering only one fresh ET cycle. It was the same when considering subsequent frozen ET (FET) cycles (51.78% vs 42.81%; ￥30 703.02 (US$4564.62) vs ￥24 740.95 (US$3678.24)). The results of most subgroups were consistent with the results of the basic analysis. However, for certain populations, the long protocol was the inferior protocol (less effective and more expensive).
CONCLUSIONS: For the Chinese population, when the monetary value per live birth was greater than ￥65 420 (US$9726) and ￥66 400 (US$9872), respectively, considering only one fresh cycle and considering subsequent frozen cycles, the long protocol is the preferred protocol. This threshold also varies for women of different ages and ovarian response capacities. For women in POSEIDON (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number) group 2, group 3 and group 4, antagonist protocol is recommended as the preferred protocol. The results of this study need to be verified by further large-scale randomised controlled trials.

Male infertility is a major concern affecting reproductive health. Biallelic deleterious variants of most DNAH gene family members have been linked to male infertility, with intracytoplasmic sperm injection (ICSI) being an efficacious way to achieve offspring. However, the association between DNAH12 and male infertility is still limited. Here, we identified one homozygous variant and two compound heterozygous variants in DNAH12 from three infertile Chinese men. Semen analysis revealed severe asthenozoospermia, abnormal morphology, and structure of sperm flagella. Furthermore, the Dnah12 knock-out mouse revealed severe spermatogenesis failure and validated the same male infertility phenotype. Favorable fertility outcomes were achieved through ICSI in three human individuals and Dnah12 knock-out mice. Collectively, our study indicated that biallelic variants of DNAH12 can induce male infertility in both human beings and mice. Notably, evidence from DNAH12 enhanced that ICSI was an optimal intervention to achieve favorable fertility outcomes for infertile males with DNAH gene family variants.

Premature ovarian failure (POF) is a complex and heterogeneous disease that causes infertility and subfertility. However, the molecular mechanism of POF has not been fully elucidated. Here, we show that the loss of adenylyl cyclase III (Adcy3) in female mice leads to POF and a shortened reproductive lifespan. We found that Adcy3 is abundantly expressed in mouse oocytes. Adcy3 knockout mice exhibited the excessive activation of primordial follicles, progressive follicle loss, follicular atresia, and ultimately POF. Mechanistically, we found that mitochondrial oxidative stress in oocytes significantly increased with age in Adcy3-deficient mice and was accompanied by oocyte apoptosis and defective folliculogenesis. In contrast, compared with wild-type female mice, humanized ADCY3 knock-in female mice exhibited improved fertility with age. Collectively, these results reveal that the previously unrecognized Adcy3 signaling pathway is tightly linked to female ovarian aging, providing potential pharmaceutical targets for preventing and treating POF.

Over the past few years, there has been growing interest in developing new methods of embryo quality assessment to improve the outcomes of assisted reproductive technologies in the medical field. Raman microscopy as an increasingly promising analytical tool has been widely used in life sciences, biomedicine and \"omics\" to study molecular, biochemical components, living cells and tissues due to the label-free and non-destructive nature of the imaging technique. This paper reviews the analytical capability of Raman microscopy and applications of Raman spectroscopy technology mainly in reproductive medicine. The purpose of this review is to introduce the Raman spectroscopy technology, application and underlying principles of the method, to provide an intact picture of its uses in biomedical science and reproductive medicine, to offer ideas for its future application, verification and validation. The focus is on the application of Raman spectroscopy in the reproductive medicine field, including the application in gametes, embryos and spent embryo culture media.

OBJECTIVE: Pregnancy outcomes of different ovarian stimulation protocols for in vitro fertilisation/intracytoplasmic sperm injection (IVF/ICSI) in patients with adenomyosis are not explicit. This meta-analysis aimed to systematically evaluate the effects of different IVF/ICSI protocols on pregnancy outcomes.
METHODS: Meta-analysis.
METHODS: PubMed, Web of Science and Cochrane library were searched up to October 2023.
METHODS: Comparative studies on IVF/ICSI outcomes in the adenomyosis population were eligible. Studies on preimplantation genetic testing, reviews, case reports and animal experiments were excluded.
METHODS: Valid information was extracted by two independent authors according to a standard data format. All analyses were conducted using Review Manager (RevMan, V.5.3).
RESULTS: Compared with the non-adenomyosis population, adenomyosis was responsible for a 26% reduction in clinical pregnancy rate (CPR; 42.47% vs 55.89%, OR: 0.74, 95% CI: 0.66 to 0.82, p<0.00001), a 35% reduction in live birth rate (LBR; 30.72% vs 47.77%, OR: 0.65, 95% CI: 0.58 to 0.73, p<0.00001) and a 1.9-fold increase in miscarriage rate (MR; 27.82% vs 13.9%, OR: 1.90, 95% CI: 1.56 to 2.31, p<0.00001). Subgroup analysis suggested that, in fresh embryo transfer (ET) cycles, the CPR (34.4% vs 58.25%) in the long/short/antagonist protocol group was poorer than that in the ultralong protocol group. In frozen ET (FET) cycles, there were no statistical differences in CPR ((GnRHa+FET) AM(adenomyosis) vs non-AM: 51.32% vs 43.48%, p=0.31; (non-GnRHa+FET) AM vs non-AM: 50.25% vs 60.10%, p=0.82), MR ((GnRHa+FET) AM vs non-AM:12.82% vs 12.50%, p=0.97; (non-GnRHa+FET) AM vs non-AM: 30.5% vs 15.54%, p=0.15) and LBR ((GnRHa+FET) AM vs non-AM:44.74% vs 36.96%, p=0.31; (non-GnRHa+FET) AM vs non-AM: 34.42% vs 50.25%, p=0.28). The MR in the adenomyosis group was high in the fresh ET and FET cycles.
CONCLUSIONS: FET might be a better choice for women with adenomyosis, especially those pretreated with GnRHa. In fresh ET cycles, pregnancy outcomes of the long/short/antagonist protocols were poorer than those of the ultralong protocol.
BACKGROUND: CRD42022340743.

There is a global trend of declining fertility among people of childbearing age and mankind is confronted with great challenges of fertility problems. As a result, fertility preservation technology has emerged. Fertility preservation involves interventions and procedures aimed at preserving the patients\' chances of having children when their fertility may have been impaired by their medical conditions or the treatments thereof, for example, chemotherapy and/or radiotherapy for cancer. The changes in patients\' fertility can be temporary or permanent damage. Fertility preservation can help people diagnosed with cancer or other non-malignant diseases. More and more fertility preservation methods are being used to preserve the fertility of cancer patients and protect their reproductive organs from gonadotoxicity. Fertility preservation may be appropriate for young patients with early-stage cancers and good prognosis before they undergo treatments (chemotherapy and/or radiotherapy) that can negatively affect their fertility. It is also appropriate for patients with chronic conditions or those who have encountered environmental exposures that affect their gonadal function. Fertility preservation methods include oocyte cryopreservation, embryo cryopreservation, and ovarian tissue cryopreservation (OTC) for women and sperm freezing and testicular tissue freezing for men. The survival rates of children and adolescents diagnosed with malignant tumors have been steadily increasing as a result of advances in cancer treatments. Cryopreservation of oocytes and sperm is recognized as a well-established and successful strategy for fertility preservation in pubertal patients. OTC is the sole option for prepubertal girls. On the other hand, cryopreservation of immature testicular tissue remains the only alternative for prepubertal boys, but the technology is still in the experimental stage. A review showed that the utilization rate of cryopreserved semen ranged from 2.6% to 21.5%. In the case of cryopreserved female reproductive materials, the utilization rate ranged from 3.1% to 8.7% for oocytes, approximately from 9% to 22.4% for embryos, and from 6.9% to 30.3% for ovarian tissue. When patients have needs for fertility treatment, cryopreserved vitrified oocytes are resuscitated and in vitro fertilization-embryo transfer (IVF-ET) was performed to help patients accomplish their reproductive objectives, with the live birth rate (LBR) being 32%. On the other hand, when cryopreserved embryos are resuscitated and transferred, the LBR was 41%. OTC has the advantage of restoring natural fertility and presents a LBR of 33%, compared with the LBR of 19% among 266 IVF patients. In addition, OTC has the benefit of restoring the endocrine function. It has been observed that the shortest recovery time of the first menstruation after transplantation was 3.9 months, and the recovery rate of ovarian function reached 100%. To date, a growing number of cancer survivors and patients with other diseases are benefiting from fertility preservation measures. In the face of declining human fertility, fertility preservation provides a new approach to human reproduction. Fertility preservation should be applied in line with the ethical principles so as to fully protect the rights and interests of patients and their offsprings.

BACKGROUND: Balanced insertional translocations (BITs) can increase the risk of infertility, recurrent miscarriages or neonatal birth defects due to chromosomal imbalances in gametes. However, studies on preimplantation genetic testing (PGT) for patients carrying BITs are inadequate.
METHODS: A preimplantation genetic genotyping and haplotype analysis approach was developed and implemented in this study. Genome-wide SNP genotyping was performed, followed by core family-based haplotype analysis. The balanced insertion segments in euploid embryos were inferred from the haplotypes inherited from the carrier parent.
RESULTS: A total of 10 BIT carrier couples were enrolled in our study. 15 in vitro fertilisation cycles were conducted, resulting in 73 blastocysts biopsied and subjected to PGT analysis. Among these, 20 blastocysts displayed rearrangement-related imbalances, 13 exhibited de novo aneuploidies, 15 presented a complex anomaly involving both imbalances and additional aneuploidies, while 25 were euploid. Within the euploid embryos, 12 were balanced carrier embryos and 13 were non-carrier embryos. To date, eight non-carrier and one carrier embryos have been transferred, resulting in seven clinical pregnancies. All pregnancies were recommended to perform prenatal diagnosis, our date revealed complete concordance between fetal genetic testing results and PGT results. Presently, five infants have been born from these pregnancies, and two pregnancies are still ongoing.
CONCLUSIONS: The proposed method facilitates comprehensive chromosome screening and the concurrent identification of balanced insertions or normal karyotypes in embryos. This study offers an effective and universally applicable strategy for BIT carriers to achieve a healthy pregnancy and prevent the transmission of BITs to their offspring.

Singapore, a highly affluent island city-state located in Southeast Asia, has increasingly leveraged new assisted reproductive technologies (ART) to overcome its dismal fertility rates in recent years. A new frontier in ART is preimplantation genetic testing (PGT) for polygenic risk scores (PRS) to predict complex multifactorial traits in IVF (in vitro fertilisation) embryos, such as type 2 diabetes, cardiovascular diseases and various other characteristics like height, intelligence quotient (IQ), hair and eye colour. Unlike well-known safety risks with human genome editing, there are negligible risks with PGT-P, because there are no man-made genetic modifications that can be transmitted to future generations. Nevertheless, the current efficacy of using PGT-P to select IVF embryos for either increased or decreased probability of developing specific polygenic traits is still far from certain. Hence, the regulatory safeguards proposed here will be based on the assumption that the efficacy of this new technology platform has already been validated. These include: (1) restricting the application of PGT-P only for prevention of clinically relevant polygenic disease traits, (2) securely blocking patients\' access to the raw genomic DNA sequencing data of their IVF embryos, (3) validating diagnosis of polygenic disease traits in the prospective parents/grandparents of IVF embryos, and restricting PGT-P only for preventing specifically diagnosed polygenic disease traits and (4) mandating rigorous and comprehensive genetic counselling for IVF patients considering PGT-P. There is an urgent and dire need to prevent abuse of the PGT-P technique, as well as protect the interests and welfare of patients if its clinical application is to be permitted in the country.