From live birth to live birth: a strong correlation between the outcomes of first and second frozen-thawed euploid blastocyst transfers from sibling oocytes.

Purpose: To investigate any correlation between the outcomes of the first euploid frozen-thawed blastocyst embryo transfer (FBT) and the subsequent euploid FBT derived from sibling oocytes.

Methods: This retrospective study analyzed data from 1051 women who underwent preimplantation genetic testing for aneuploidy and had a euploid FBT. Of these patients, 159 underwent a second transfer.

Ovarian tissue cryopreservation in breast cancer patients: glass half empty or glass half full?

This is a commentary to a paper recently published in RBMOnline by Macklon and De Vos, in which they argue for a discontinuation of ovarian tissue freezing for fertility preservation in women with breast cancer. Instead, they suggest the use of oocyte vitrification following ovarian stimulation as the preferred method of fertility preservation. This commentary presents nine separate arguments that should be considered in the context of ovarian tissue freezing and fertility preservation in girls and women.

Defects in meiosis I contribute to the genesis of androgenetic hydatidiform moles.

To identify novel genes responsible for recurrent hydatidiform moles (HMs), we performed exome sequencing on 75 unrelated patients who were negative for mutations in the known genes. We identified biallelic deleterious variants in 6 genes, FOXL2, MAJIN, KASH5, SYCP2, MEIOB, and HFM1, in patients with androgenetic HMs, including a familial case of 3 affected members. Five of these genes are essential for meiosis I, and their deficiencies lead to premature ovarian insufficiency.

Identification of diagnostic genes and the miRNA‒mRNA‒TF regulatory network in human oocyte aging via machine learning methods.

Purpose: Oocyte aging is a significant factor in the negative reproductive outcomes of older women. However, the pathogenesis of oocyte aging remains unclear. This study aimed to identify the hub genes involved in oocyte aging via bioinformatics methods.

A multicycle approach through DuoStim with a progestin-primed ovarian stimulation (PPOS) protocol: a valuable option in poor prognosis patients undergoing PGT-A.

Purpose: This study is to evaluate the effectiveness of a PPOS protocol in poor prognosis patients undergoing IVF with DuoStim and PGT-A versus the conventional protocol with GnRH antagonist.

Methods: Retrospective cohort study encompassing 444 couples obtained matching one PPOS-DuoStim with two antagonist-DuoStim cycles at a private IVF center between 2020 and 2023 (average maternal age: 40 years, average cumulus-oocyte complexes collected after the first stimulation: 5). The study was powered to exclude a two-sided different euploid blastocyst rate per MII oocytes (EBR per MII) in the two groups (alpha = 0.

Addition of granulocyte macrophage colony stimulating factor (GM-CSF) during oocyte maturation improves embryo development in a mouse model of advanced maternal age.

Oocyte developmental competence declines in women aged 35 and older resulting in many women resorting to IVF. The present study determined whether adding Granulocyte-macrophage colony-stimulating factor (GM-CSF) during in vitro oocyte maturation (IVM) could improve oocyte developmental competence in a mouse model of advanced maternal age. Oocytes from 12-14 month C57BL6 J × CBA mice were treated with 10 ng/ml of GM-CSF during IVM, and embryo development, mitochondrial activity, spindle formation and chromosomal alignment were examined.

Long-term follow up of fecundability after ectopic pregnancy in Taiwan: a nationwide population-based study.

Background: Ectopic pregnancy (EP) occurs when a fertilized ovum is implanted outside the uterine cavity. Its incidence is 2% of all pregnancies and is known to decrease fertility. This study aimed to measure pregnancy rates after EP, identify the various parameters influencing pregnancy, and compare these variables in women with and without a history of EP, as well as determine in which medical facilities women with EP seek medical help.

Oocyte death is triggered by the stabilization of TAp63α dimers in response to cisplatin.

The TAp63α protein is highly expressed in primordial follicle oocytes, where it typically exists in an inactive dimeric form. Upon DNA damage, TAp63α undergoes hyperphosphorylation, transitioning from a dimeric to a tetrameric structure, which initiates oocyte apoptosis by upregulating pro-apoptotic gene. Our results demonstrate that cisplatin, an alkylating anti-cancer agent, predominantly produced the TAp63α dimer rather than the tetramer.

ICSI and PGT-A in PCOS phenotype-D patients: a matched case-control study versus idiopathic infertile women.

Purpose: To assess oocyte competence and embryo chromosomal constitution in phenotype-D PCOS women undergoing ICSI for PGT-A at the blastocyst stage.

Methods: Retrospective study at a private IVF center. In the period 2013-2021, 58 naïve phenotype-D PCOS women (i.

High proportion of zygotes with multiple pronuclei increase the embryo multinucleation rate during conventional IVF.

The incidence of multiple pronuclei (≥ 3PN) zygotes and blastomere multinucleation was found to be elevated in the presence of increased estradiol (E) levels and a greater number of retrieved oocytes. This implies a potential link between the incidence of multinucleation at the two-cell stage (MN2) and a higher proportion of ≥ 3PN zygotes. We aimed to investigate the effect of high proportion of ≥ 3PN zygotes on MN2 incidence during conventional in vitro fertilization (C-IVF) by using time-lapse monitoring.

One fresh cleavage-stage single embryo transfer (SET) plus one frozen-thawed blastocyst-stage SET or one fresh cleavage-stage double embryo transfer? A retrospective matched cohort study.

Study Question: Are there significant differences in fertility outcomes between transferring two cleavage-stage embryos in a single fresh cycle and transferring one cleavage-stage embryo in a fresh cycle and one blastocyst-stage embryo in the subsequent frozen-thawed cycle?

Summary Answer: In women aged <38 years with two embryos available, transferring one cleavage-stage embryo in a fresh cycle and one blastocyst-stage embryo in the subsequent frozen-thawed cycle increased live birth rates and decreased multiple live birth rates compared to transferring two cleavage-stage embryos in a single fresh cycle.

What Is Known Already: The strategy of repeated single embryo transfer (SET) has emerged as a solution to address the reduced live birth rates associated with SET per cycle. There is substantial evidence indicating that the cumulative live birth rate after repeated SET is comparable to that of double embryo transfer (DET), while significantly reducing the incidence of multiple pregnancies.

Exceptional longevity of mammalian ovarian and oocyte macromolecules throughout the reproductive lifespan.

The mechanisms contributing to age-related deterioration of the female reproductive system are complex, however aberrant protein homeostasis is a major contributor. We elucidated exceptionally stable proteins, structures, and macromolecules that persist in mammalian ovaries and gametes across the reproductive lifespan. Ovaries exhibit localized structural and cell-type-specific enrichment of stable macromolecules in both the follicular and extrafollicular environments.

Outcomes of female fertility preservation with cryopreservation of oocytes or embryos in the Netherlands: a population-based study.

Study Question: What are the reproductive outcomes of patients who cryopreserved oocytes or embryos in the context of fertility preservation in the Netherlands?

Summary Answer: This study shows that after a 10-year follow-up period, the utilization rate to attempt pregnancy using cryopreserved oocytes or embryos was 25.5% and the cumulative live birth rate after embryo transfer was 34.6% per patient.

A microfluidic hanging droplet as a programmable platform for mammalian egg vitrification.

Egg (oocyte) vitrification is the dominant method for preserving fertility for women of reproductive age. However, the method is typically performed by hand, requiring precise (∼0.1 to 10 μL) and time-sensitive (∼1 s) liquid exchange of cryoprotectants (CPA) around eggs as well as fine handling of eggs (∼100 μm) for immersion into liquid nitrogen (LN).

Chronic psychosocial stress affects insulin-like growth factor 1 and its receptors in mouse ovaries.

Context Chronic psychosocial stress negatively affects folliculogenesis and oogenesis. Intraovarian mechanisms mediating these effects are poorly understood. Aims This work aimed to find out how chronic psychosocial stress affects ovarian IGF1 and its receptor (IGF1R), as well as Igf1 and Igf1r gene expression in cumulus-oocyte complexes (COCs).

Multi-omics approach to reveal follicular metabolic changes and their effects on oocyte competence in PCOS patients.

Background: Polycystic ovary syndrome (PCOS) is a common heterogeneous disorder linked with endocrine and metabolic disturbances. The underlying mechanism of PCOS, especially its effect on oocyte competence, remains unclear. The study aimed to identify abnormal follicular metabolic changes using a multi-omics approach in follicular fluid from PCOS patients and to determine their effects on oocyte competence.

THE RELATIONSHIP BETWEEN FOLLICLE SIZE, OOCYTE MATURATION, BLASTOCYST FORMATION, BLASTOCYST PLOIDY, AND PREGNANCY OUTCOMES IN YOUNG WOMEN UNDERGOING IVF.

Unlabelled: The relationship between follicle size, oocyte quality, and blastocyst ploidy is not fully established. This question becomes especially important for poor responders and older reproductive age women, where optimal follicle size and oocyte quantity cannot always be achieved during ovarian stimulation. The aim of this study is to determine the relationship between follicle size, oocyte maturation, blastocyst formation, blastocyst ploidy, and pregnancy outcomes in young women undergoing in vitro fertilization (IVF).

Low microbial abundance and community diversity in the egg capsule of the oviparous cloudy catshark (Scyliorhinus torazame) during oviposition.

Vertebrate embryos are protected from bacterial infection by various maternally derived factors, yet little is known about the defence mechanisms in elasmobranchs. This study aimed to characterize the intracapsular environment of freshly laid eggs of the oviparous catshark (Scyliorhinus torazame) by investigating the microbial abundance and microbiota to understand its potential contribution to embryonic defence. The egg capsule of oviparous elasmobranchs is tightly sealed until pre-hatching, after which seawater flows into the capsule, exposing the embryos to the surrounding seawater.

Transgenerational transmission of post-zygotic mutations suggests symmetric contribution of first two blastomeres to human germline.

Little is known about the origin of germ cells in humans. We previously leveraged post-zygotic mutations to reconstruct zygote-rooted cell lineage ancestry trees in a phenotypically normal woman, termed NC0. Here, by sequencing the genome of her children and their father, we analyze the transmission of early pre-gastrulation lineages and corresponding mutations across human generations.