Comparative analysis of long versus short co-incubation of gametes on post-insemination outcomes and embryo morphokinetics.

Research Question: Does a short co-incubation of gametes in conventional IVF affect post-insemination outcomes and embryo morphokinetics?

Design: Sibling oocyte randomized pilot study conducted between December 2020 and March 2023. Eligible couples (n = 55) were women aged 18-43 years with BMI 35 km/m or lower and male normal semen parameters. Cumulus oocyte complexes (COC) (six to 12) were randomized in a 1:1:2 proportion in long (16-18 h) or short (2 h) co-incubation IVF exposure and ICSI, respectively.

The First Lugano Workshop on the role of adenomyosis in ART.

Adenomyosis is an important clinical condition with uncertain prevalence, and clinical focus on adenomyosis in patients undergoing assisted reproductive technology (ART) has increased during recent years. Recognizing the limited clinical knowledge on the impact of adenomyosis on ART outcomes, the First Lugano Adenomyosis Workshop was a symposium involving experts in the field of adenomyosis, covering basic research, imaging, surgery and infertility to highlight current advances and future research areas over a wide range of topics related to adenomyosis. Adenomyosis is characterized by altered oestrogen and progesterone signalling pathways.

Private versus funded infertility care: not a challenge but a call for cooperation.

Private medical care has significantly contributed to the advancement of various medical fields. The birth of private IVF groups in the 1990s led to improvements in stimulation protocols, embryo culture, intracytoplasmic sperm injection, vitrification and preimplantation genetic testing. However, infertility is often misunderstood as a disease, leading to low birth rates and a lack of awareness among the general population.

Assessing the clinical value of day 7 blastocysts: a predictive model for preimplantation genetic testing for aneuploidy (PGT-A) cycles.

Purpose: To identify the benefit of extending embryo culture until day (D)7 based on patients and cycle characteristics.

Methods: A retrospective cohort study was conducted including 25,120 blastocysts from 5278 PGT-A autologous cycles between 2017 and 2022. A theoretical cumulative live birth rate (CLBR) was calculated by binomial density function.

Steady morphokinetic progression is an independent predictor of live birth: a descriptive reference for euploid embryos.

Study Question: Can modelling the longitudinal morphokinetic pattern of euploid embryos during time-lapse monitoring (TLM) be helpful for selecting embryos with the highest live birth potential?

Summary Answer: Longitudinal reference ranges of morphokinetic development of euploid embryos have been identified, and embryos with steadier progression during TLM are associated with higher chances of live birth.

What Is Known Already: TLM imaging is increasingly adopted by fertility clinics as an attempt to improve the ability of selecting embryos with the highest potential for implantation. Many markers of embryonic morphokinetics have been incorporated into decision algorithms for embryo (de)selection.

A novel antimüllerian gene mutation in a woman with high antral follicle count and extremely low serum antimüllerian hormone levels.

Objective: To report a case with a distinct difference between the ovarian reserve parameters of antimüllerian hormone (AMH) levels, antral follicle count (AFC), and follicle-stimulating hormone levels caused by a novel homozygous missense variant in the exon 1 of the gene [NM_000479.4:c259G>A, p.(Val87Met)].

Primary sex ratio in euploid embryos of consanguine couples after IVF/ICSI.

Purpose: To assess the primary sex ratio (males-to-females at time of conception) in blastocysts from consanguine couples undergoing IVF/ICSI treatments and its correlation with chromosomal constitution.

Method: A total of 5135 blastocysts were analyzed by preimplantation-genetic testing for aneuploidy (PGT-A) with next-generation sequencing (NGS) from November 2016 to December 2020. From those, a total of 1138 blastocysts were from consanguine couples (CS) and 3997 from non-consanguine couples (NCS).

Association of 'normal' early follicular FSH concentrations with unexpected poor or suboptimal response when ovarian reserve markers are reassuring: a retrospective cohort study.

Research Question: Are basal FSH measurements, when elevated within its normal range, useful for assessing overall ovarian response and predicting unexpected poor or suboptimal ovarian response?

Design: Retrospective cohort study of ovarian stimulation cycles.

Results: A total of 1058 ovarian stimulation cycles (891 first, 167 repeated) were included. Anti-Müllerian hormone (AMH) values were categorized into four (0 to ≤0.

Features of chromosomal abnormalities in relation to consanguinity: analysis of 10,556 blastocysts from IVF/ICSI cycles with PGT-A from consanguineous and non-consanguineous couples.

Consanguineous marriage is defined as marriage between first or second-degree cousins, with high prevalence in many cultures and societies. Descendants from consanguineous unions have an increased risk for genetic diseases. Additionally, in consanguineous couples, chromosomal disjunction during embryogenesis could also be affected, increasing the risk of chromosomal errors.

Embryo Culture Medium Has No Impact on Mosaicism Rates: a Sibling Oocyte Study.

Human embryos cultured in vitro can contain two or more cytogenetically distinct cell lineages known as "chromosomal mosaicism". Since mosaicism is produced by mitotic errors after fertilization occurs, culture conditions might contribute to mosaicism origins. Many studies demonstrated that euploidy rates are not affected by culture media; however, whether oocytes cultured under continuous culture media (CCM) or sequential culture media (SCM) has a higher risk of mosaicism occurring remains unsolved.

Interindividual variation of progesterone elevation post LH rise: implications for natural cycle frozen embryo transfers in the individualized medicine era.

Background: The key to optimal timing of frozen embryo transfer (FET ) is to synchronize the embryo with the receptive phase of the endometrium. Secretory transformation of the endometrium is induced by progesterone. In contrast, detection of the luteinizing hormone (LH) surge is the most common surrogate used to determine the start of secretory transformation and to schedule FET in a natural cycle.

Clinical and laboratory parameters associated with cycle outcomes in patients undergoing euploid frozen blastocyst transfer.

Research Question: Which factors impact on clinical pregnancy rate (CPR) and live birth rates (LBR) in euploid frozen embryo transfer (eFET) cycles?

Design: Retrospective observational study including 1660 eFET cycles with 2439 euploid blastocysts, from November 2016 to December 2020. The impact of clinical and laboratory parameters on CPR, biochemical miscarriage rate (BMR), clinical miscarriage rate (CMR) and LBR was evaluated.

Results: CPR per transfer was 63.

Frozen embryo transfers in a natural cycle: how to do it right.

Purpose Of Review: Assisted reproductive technology treatment has seen a significant shift from fresh to frozen embryo transfers (FET). Endometrial receptivity in the FET cycle can be achieved through a hormonal replacement cycle or a natural cycle, and the preparation approach has important implications on the pregnancy itself. In the natural cycle approach, planning of the embryo transfer timing might be challenging due to the need to identify ovulation correctly.

Effect of the endometrial thickness on the live birth rate: insights from 959 single euploid frozen embryo transfers without a cutoff for thickness.

Objective: To investigate whether endometrial thickness (ET) independently affects the live birth rate (LBR) after embryo transfer.

Design: Retrospective study.

Setting: Private assisted reproductive technology center.

ART outcome after euploid frozen embryo transfer is not affected by previous Cesarean section delivery in the absence of intracavitary fluid.

Purpose: To evaluate the impact of a cesarean section (CS) on the chance of clinical pregnancy and live birth (LB) in frozen embryo transfer (FET) cycles in the setting of euploid embryos and the absence of intracavitary fluid (ICF) as causes of implantation failure were excluded.

Methods: Retrospective study, including patients with at least one previous CS or at least one previous vaginal delivery, who underwent a euploid FET cycle.

Results: A total of 412 euploid embryo transfer cycles had been included.