Lessons learned from 64,071 embryos subjected to PGT for aneuploidies: results, recurrence pattern and indications analysis.

Research Question: What is the influence of biological, technical and clinical factors on embryo outcomes in preimplantation genetic testing for aneuploidies (PGT-A) and what is the recurrence pattern?

Design: This retrospective study included 64,071 embryos undergoing PGT-A in the same laboratory between 2011 and 2019. Biopsies were performed at the day 3 embryo stage (48.32%) or blastocyst stage (51.

Factors influencing natural fecundity in fertile couples: a survey of puerperae and their partners.

Research Question: What is the fecundity rate among fertile couples, and which factors influence it?

Design: Retrospective study of all puerperae attending Cruces University Hospital Human Reproduction Unit over 9 months. An anonymous questionnaire was circulated to all patients, and 2510 valid completed questionnaires were collected. The main inclusion criterion was natural conception resulting in delivery.

Safety of Plasma Rich in Growth Factors (PRGF) as additive to healthy human sperm samples: a pilot study.

Objective: The aim of our study was to assess if the addition of PRGF to healthy human sperm affects its motility and vitality.

Methods: This was a prospective study, with 44 sperm donors on whom sperm analysis was performed. Nine mL of blood was collected and PRGF was obtained using PRGF-Endoret® technology.

Comparison of the Administration of 150 or 75 of Recombinant LH in Agonist ICSI Cycles Stimulated with Recombinant FSH in Women Aged 35-39: A Comparative Study.

Background: The purpose of the study was to assess whether the coadministration of 150 of recombinant LH instead of 75 in women aged 35-39 improves the results in agonist ICSI cycles stimulated with 300 of recombinant FSH.

Methods: In this study, two ovarian stimulation protocols coexisted which were identical except in the administered dose of recombinant LH, for which some patients received 150 (n=231) and some received 75 (n=216). Both groups received 300 of recombinant FSH.

Early Spontaneous Twinning Recorded By Time-Lapse.

Monozygotic twins (MZT) are 2.5 times more frequent in ART than in natural conceptions. A number of ART-related mechanisms have been probably linked with MZT.

Cell-cell interactions during the formation of primordial follicles in humans.

Gametogenesis is a complex and sex-specific multistep process during which the gonadal somatic niche plays an essential regulatory role. One of the most crucial steps during human female gametogenesis is the formation of primordial follicles, the functional unit of the ovary that constitutes the pool of follicles available at birth during the entire reproductive life. However, the relation between human fetal germ cells (hFGCs) and gonadal somatic cells during the formation of the primordial follicles remains largely unexplored.

Natural killer cell subsets in endometrial fluid: a pilot study of their association with the endometrial cycle and reproductive parameters.

Purpose: To investigate if there are natural killer (NK) cells in endometrial fluid (EF) and their relationship with the endometrial cycle and reproductive parameters.

Methods: The population under study consisted of 43 women aged 18-40 undergoing infertility workup at our University Hospital in 2021-2022. The EF samples were obtained at the first visit to our unit, on occasion of the mock embryo transfer.

Evaluation of costs associated with fertility treatment leading to a live birth after one fresh transfer: A global perspective.

Considerable costs are associated with infertility treatment, but little evidence is available on the main drivers of treatment costs. This cost analysis investigated key costs for treatment with assisted reproductive technology (ART) and the proportion of costs attributed to the acquisition of recombinant human follicle-stimulating hormone (r-hFSH) alfa originator for one fresh embryo transfer (ET) leading to a live birth in Spain, Norway, the UK, Germany, Denmark, South Korea, Australia, and New Zealand. The total costs for one ART cycle with a fresh ET leading to a live birth varied between countries (€4108-€12,314).

Perinatal outcomes in lesbian couples employing shared motherhood IVF compared with those performing artificial insemination with donor sperm.

Study Question: In lesbian couples, is shared motherhood IVF (SMI) associated with an increase in perinatal complications compared with artificial insemination with donor sperm (AID)?

Summary Answer: Singleton pregnancies in SMI and AID had very similar outcomes, except for a non-significant increase in the rate of preeclampsia/hypertension (PE/HT) in SMI (recipient's age-adjusted odds ratio (OR) = 1.9, 95% CI = 0.7-5.

Delta and kappa opioid receptors in human endometrium during the menstrual cycle: Expression and localization.

Objective: Endogenous opioid peptides were reported to be involved in the regulation of reproductive physiology and their precursors and receptors were described in many of the male and female reproductive tissues. Mu opioid receptor (MOR) was described in human endometrial cells and its expression and localization changed during the menstrual cycle. However, there is no data from the distribution of the other opioid receptors: Delta (DOR) and Kappa (KOR).

Polycystic ovarian syndrome and miscarriage in IVF: systematic revision of the literature and meta-analysis.

Purpose: To evaluate the risk of miscarriage in IVF cycles in women with PCOS.

Methods: Systematic review and meta-analysis. Systematic search of MEDLINE, EMBASE and Google Scholar.

Endometriosis Increases the Risk of Placenta Previa in Both IVF Pregnancies and the General Obstetric Population.

Is there a relationship between endometriosis and placenta previa (PP)? To investigate if there is a relationship between endometriosis and PP, a retrospective study was carried out, using prospectively recorded data from two different databases from Cruces University Hospital. Two different populations were included in the study. The ART (assisted reproduction techniques) population consisted of 246 cesarean sections (CS), from a total of 1170 deliveries, and the obstetric population consisted of 7045 CS, from a total of 50,298 deliveries.

Aspiration of excess follicles before intrauterine insemination in high response cycles.

Purpose: To assess the outcome of excess follicle aspiration before intrauterine insemination (EFABI) in intrauterine insemination (IUI) cycles with 4-6 follicles ≥14 mm.

Methods: A retrospective case-control study with 1559 patients undergoing IUI (donor and husband's sperm), of whom 86 underwent EFABI. We studied also an historical series of 2213 patients before EFABI implementation.

Physical activity and sperm quality: influence in sperm donors.

Purpose: To ascertain whether physical activity (PA) is associated with better sperm quality in sperm donors.

Methods: A prospective case-control study was designed in an IVF center setting. A total of 207 sperm donation candidates from a relatively small geographical area were included in the study with no intervention.

Originator recombinant human follitropin alfa versus recombinant human follitropin alfa biosimilars in Spain: A cost-effectiveness analysis of assisted reproductive technology related to fresh embryo transfers.

This study compared the cost per live birth and cost-effectiveness of the originator recombinant human follicle-stimulating hormone follitropin alfa (r-hFSH-alfa) and r-hFSH-alfa biosimilars for ovarian stimulation prior to assisted reproductive technology treatment in Spain. A decision tree model was developed, comprising pregnancy and live birth for one treatment cycle with fresh embryo transfer. Clinical inputs were based on a recent meta-analysis by Chua et al.

Transcriptional progression during meiotic prophase I reveals sex-specific features and X chromosome dynamics in human fetal female germline.

During gametogenesis in mammals, meiosis ensures the production of haploid gametes. The timing and length of meiosis to produce female and male gametes differ considerably. In contrast to males, meiotic prophase I in females initiates during development.

Effect of vitamin E administered to men in infertile couples on sperm and assisted reproduction outcomes: a double-blind randomized study.

Objective: To evaluate the influence on sperm parameters and in vitro fertilization (IVF) outcomes of the administration of 400 mg/day of vitamin E for 3 months to men from infertile couples who are undergoing IVF.

Design: Double-blind, placebo-controlled, randomized study.

Setting: Human reproduction unit of a university hospital.

Antibacterial and Antifungal Activity of the Human Endometrial Fluid during the Natural Cycle.

Purpose: Some microbiota patterns have been associated with favorable IVF prognosis and others with pathological conditions. The endometrial fluid aspirate (EFA) contains antibacterial proteins that are enriched in implantative IVF cycles, but the antimicrobial effect of EFA has not been addressed. We aimed to evaluate the antimicrobial activity of the human endometrial fluid during the natural cycle.

Proteomics based drug repositioning applied to improve in vitro fertilization implantation: an artificial intelligence model.

Embryo implantation is one of the most inefficient steps in assisted reproduction, so the identifying drugs with a potential clinical application to improve it has a strong interest. This work applies artificial intelligence and systems biology-based mathematical modeling strategies to unveil potential treatments by computationally analyzing and integrating available molecular and clinical data from patients. The mathematical models of embryo implantation computationally generated here simulate the molecular networks underneath this biological process.

Meta-analysis of the embryo freezing transfer interval.

Background: The decision of whether frozen embryo transfer (FET) should be performed in the cycle immediately after OPU or at least one cycle later is controversial. FET could improve pregnancy rates in IVF; however, how much time is needed for the endometrium to return to optimal receptivity after ovarian stimulation is not known.

Methods: Electronic search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials to identify studies providing data on the influence of the interval between embryo freezing (or OPU) and FET in FET cycles published between January 1, 2007, and February 1, 2020.

Women's vitamin D levels and IVF results: a systematic review of the literature and meta-analysis, considering three categories of vitamin status (replete, insufficient and deficient).

To investigate the influence of vitamin D status on fertilisation (IVF) results, a meta-analysis of 15 cohort studies of 3711 women undergoing IVF was performed. Women were classified into three groups according their vitamin D levels (≥30 ng/mL considered replete/sufficient; 21-29 ng/mL insufficient and <20 ng/mL deficient). Three different meta-analyses were performed: (i) sufficient vs deficient; (ii) sufficient vs 'insufficient + deficient'; (iii) 'sufficient + insufficient' vs deficient.

Cervical pregnancy in assisted reproduction: an analysis of risk factors in 91,067 ongoing pregnancies.

Research Question: What is the frequency of cervical pregnancy in women undergoing assisted reproductive technologies (ART) and what are the risk factors?

Design: Case-control study of women undergoing assisted reproductive technology (ART) at 25 private assisted reproduction clinics run by the same group in Spain. Two control groups (tubal ectopic pregnancies and intrauterine pregnancies) were established. The main outcome measure was frequency of cervical pregnancy.

Oocytes of women who are obese or overweight have lower levels of n-3 polyunsaturated fatty acids compared with oocytes of women with normal weight.

Objective: To ascertain whether the oocytes of women who are obese or overweight have a different fatty acid (FA) profile than women with normal weight.

Design: Prospective case-control study.

Setting: Two IVF centers.

In-depth proteomics and natural peptidomics analyses reveal antibacterial peptides in human endometrial fluid.

The composition of endometrial fluid reflects the status of the endometrium; it is a good atraumatic source of information on embryo implantation processes and possible pathological conditions. Although some attempts have been made to characterise its proteome, the catalogue of its proteins remains incomplete and little has been done to analyse the natural peptides it contains. Here, we present a comprehensive analysis of the proteins and natural peptides of the endometrial fluid.