0000000000056525
AUTHOR
Elena Labarta
showing 15 related works from this author
Circulating progesterone levels and ongoing pregnancy rates in controlled ovarian stimulation cycles for in vitro fertilization: analysis of over 400…
2010
background: The influence of elevated serum progesterone levels during in vitro fertilization/intracytoplasmic sperm injection (IVF/ ICSI) cycles on pregnancy rates is a matter of continued debate among fertility clinicians. Efforts to resolve this question have been impeded by the various assays used to measure progesterone and the different, arbitrary threshold values for defining ‘high’ progesterone levels. methods: A non-interventional, retrospective, observational, single-centre cohort study evaluated the relationship between serum progesterone levels on the day of human chorionic gonadotrophin (hCG) administration and the ongoing pregnancy rate in 4032 patients undergoing IVF/ICSI cyc…
The follicular hormonal profile in low-responder patients undergoing unstimulated cycles: is it hypoandrogenic?
2012
STUDY QUESTION What is the final hormonal milieu of pre-ovulatory follicles of low-responder (LR) patients undergoing unstimulated cycles? SUMMARY ANSWER Neither androgen secretion nor LH was impaired in pre-ovulatory follicles of LR women. WHAT IS KNOWN ALREADY Therapies currently used to improve ovarian response in LR women have an impact on the final hormonal follicular milieu, and these changes are believed to be partially responsible for determining the success rate in these women. Surprisingly, as far as we know, there is no report of the final hormonal profile of LR women undergoing unstimulated cycles or evidence that follicular androgen secretion in LR women is impaired. STUDY DESI…
A 5-year multicentre randomized controlled trial comparing personalized, frozen and fresh blastocyst transfer in IVF.
2020
Abstract Research question Does clinical performance of personalized embryo transfer (PET) guided by endometrial receptivity analysis (ERA) differ from frozen embryo transfer (FET) or fresh embryo transfer in infertile patients undergoing IVF? Design Multicentre, open-label randomized controlled trial; 458 patients aged 37 years or younger undergoing IVF with blastocyst transfer at first appointment were randomized to PET guided by ERA, FET or fresh embryo transfer in 16 reproductive clinics. Results Clinical outcomes by intention-to-treat analysis were comparable, but cumulative pregnancy rate was significantly higher in the PET (93.6%) compared with FET (79.7%) (P = 0.0005) and fresh embr…
Defining poor prognosis markers of implantation for embryo selection by time-lapse
2012
Mitochondrial DNA content decreases during in vitro human embryo development: insights into mitochondrial DNA variation in preimplantation embryos do…
2020
Objective To assess the mitochondrial DNA (mtDNA) load and variation in human oocytes and during preimplantation embryo development using specimens donated for research. Design Prospective cohort study. Setting Not applicable. Patients A total of 50 in vitro fertilization patients and 11 oocyte donors whose specimens were obtained between July 2017 and July 2018. Interventions None. Main Outcome Measures All specimens were separately collected. Quantitative polymerase chain reaction was performed with SurePlex DNA Amplification System (Illumina). Primers for the adenosine triphosphate 8 mitochondrial gene and the β-actin were used. Data were statistically analyzed by analysis of variance wi…
Day-3 embryo metabolomics in the spent culture media is altered in obese women undergoing in vitro fertilization
2015
Objective To determine whether the global metabolomic profile of the spent culture media (SCM) of day-3 embryos is different in obese and normoweight women undergoing in vitro fertilization (IVF). Design Prospective cohort analysis. Setting IVF clinic. Patient(s) Twenty-eight young, nonsmoking women with normoweight, nonsmoking male partners with mild/normal sperm factors undergoing a first IVF attempt for idiopathic infertility, tubal factor infertility, or failed ovulation induction: obese ovulatory women (n = 12); obese women with polycystic ovary syndrome (PCOS; n=4); normoweight ovulatory women (n = 12). Intervention(s) Fifty μl of SCM collected from two day-3 embryos of each cohort. M…
GnRH agonist administration at the time of implantation does not improve pregnancy outcome in intrauterine insemination cycles: a randomized controll…
2009
Objective To assess whether GnRH agonist administration in the luteal phase improves pregnancy outcome in intrauterine insemination (IUI) cycles. Design Single-center, randomized, single-blind, placebo-controlled trial. Setting University-affiliated infertility clinic, between February 2005 and December 2007. Patient(s) Three hundred forty-four women undergoing IUI owing to mild to moderate male factor or donor sperm indication. Intervention(s) Random administration to either a single subcutaneous injection of 0.1 mg triptorelin (group A; n = 172) 8 days after hCG administration, or solvent only (group B; n=172) at the same time. Main Outcome Measure(s) Pregnancy rate was the primary outcom…
Endometrial gene expression in the window of implantation is altered in obese women especially in association with polycystic ovary syndrome
2010
Objective To determine whether luteal phase endometrial transcriptome is altered in obese women during the window of implantation (WOI), considering the presence of infertility, fat distribution and association with polycystic ovary syndrome (PCOS). Design Prospective study. Setting University-affiliated infertility clinic, between May 2007 and March 2009. Patient(s) One control group of women with normal weight (n = 4), and four study groups of obese women (n = 6 each one) according to the association with infertility, PCOS, and ovarian stimulation. Intervention(s) The endometrium was biopsied 7 days after LH surge or hCG administration in 28 women. Main Outcome Measure(s) Endometrial gene…
Endometrial receptivity is affected in women with high circulating progesterone levels at the end of the follicular phase: a functional genomics anal…
2011
Elevated serum progesterone levels at the end of the follicular phase in controlled ovarian stimulation (COS) leads to a poorer ongoing pregnancy rate in IVF cycles due to reduced endometrial receptivity. The objective of this study was to use microarray technology to compare endometrial gene expression profiles at the window of implantation according to the levels of circulating progesterone.For this prospective cohort study, microarray data were obtained from endometrial biopsies from 12 young healthy oocyte donors undergoing COS with pituitary suppression by either gonadotrophin-releasing hormone (GnRH) agonists or antagonists, and recombinant FSH. On the day of recombinant chorionic gon…
Impact of luteinizing hormone administration on gonadotropin-releasing hormone antagonist cycles: an age-adjusted analysis
2011
Objective: To analyze the impact of LH administration on cycle outcome in ovarian stimulation with GnRH antagonists. Design: Randomized, open-label, controlled trial performed in two age subgroups. Recombinant (r) FSH versus rFSH + rLH administration was compared. Setting: University-affiliated private infertility clinic. Patient(s): Up to 35 years old (n = 380) and aged 36 to 39 years (n = 340), undergoing their first or second IVF cycle. Intervention(s): Recombinant LH administration since stimulation day 1. Main Outcome Measure(s): Implantation rate, ongoing pregnancy rate. Result(s): In the young population, implantation rates were similar: 27.8% versus 28.6%, odds ratio (OR) 1.03 (95% …
Early pregnancy loss in women stimulated with gonadotropin-releasing hormone antagonist protocols according to oral contraceptive pill pretreatment.
2007
Objective To evaluate and compare the risk of early pregnancy loss in patients stimulated with GnRH antagonist protocols according to oral contraceptive pill (OCP) pretreatment. Design Retrospective case–control study. Setting Instituto Valenciano de Infertilidad. University of Valencia. Spain. Patient(s) One thousand five hundred thirty-nine patients, aged Intervention(s) Reproductive outcome was compared based on the application (or not) of OCP pretreatment: 944 women were included in the OCP group and 595 in the non-OCP group. The Student's t test was used for statistics. Main Outcome Measure(s) Pregnancy, biochemical pregnancy, ectopic pregnancy, early clinical pregnancy loss, early pre…
Moderate ovarian stimulation does not increase the incidence of human embryo chromosomal abnormalities in in vitro fertilization cycles.
2012
A high chromosomal abnormalities rate has been observed in human embryos derived from in vitro fertilization (IVF) treatments. The real incidence in natural cycles has been poorly studied, so whether this frequency may be induced by external factors, such as use of gonadotropins for ovarian stimulation, remains unknown.We conducted a prospective cohort study in a University-affiliated private infertility clinic with a comparison between unstimulated and stimulated ovarian cycles in the same women. Preimplantation genetic screening by fluorescence in situ hybridization was performed in all viable d 3 embryos.The primary objective was to compare the incidence of embryo chromosomal abnormaliti…
Hormonal and molecular characterization of follicular fluid, cumulus cells and oocytes from pre-ovulatory follicles in stimulated and unstimulated cy…
2012
background: The use of ovarian stimulation, to stimulate a multi-follicular response for assisted reproduction treatments, may force the production of oocytes from follicles that do not reach optimal maturation, possibly yielding oocytes that are not fully competent. The present study aimed to define the follicular environment and oocyte competence of unstimulated pre-ovulatory follicles, to compare it with that of similar-sized stimulated follicles. For this purpose, we analyzed the follicular hormonal milieu, the oocyte meiotic spindle, the embryo development and the cumulus cells gene expression (GE) profiles. methods and results: The study population was divided in two groups: (i) 42 oo…
Analysis of serum and endometrial progesterone in determining endometrial receptivity.
2021
Abstract STUDY QUESTION Is there a relationship between serum and endometrial progesterone (P4) levels, including P4 and metabolites (oestrone, oestradiol and 17α-hydroxyprogesterone), and endometrial receptivity? SUMMARY ANSWER Serum P4 levels were not correlated with endometrial P4, nor associated with endometrial receptivity as determined by the ERA® test; however, endometrial P4 and 17α-hydroxyprogesterone levels were positively correlated and related to endometrial receptivity by ERA. WHAT IS KNOWN ALREADY Acquisition of endometrial receptivity is governed by P4, which induces secretory transformation. A close relationship between serum P4 and pregnancy outcome is reported for hormone …