Publications (11)30.6 Total impact
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Article: Human chorionic gonadotropin (hCG) plasma levels at oocyte retrieval and IVF outcomes.
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ABSTRACT: PURPOSE: The aim of our study was to ascertain the influence of hCG levels at oocyte pick-up on IVF outcomes, and their relationship with clinical parameters. METHODS: A prospective study was performed including 473 women undergoing IVF, aged under 40 years. Blood samples to analyze hCG levels were obtained at the time of follicular aspiration, 36 h after the administration of 250 μg of recombinant hCG. RESULTS: Neither the numbers of oocytes obtained or fertilized, nor the pregnancy rate, were correlated with hCG levels. Moreover, hCG values were very similar in women who did and did not become pregnant (123.3 ± 48.7 and 117.5 ± 44.7 mUI/mL). Cases in which no oocytes were recovered after follicular aspiration had similar hCG levels to those in which more than 1 oocyte was obtained. On the other hand, hCG levels were negatively related to body mass index, weight, and age. CONCLUSIONS: These data indicate that after the administration of 250 μg of recombinant hCG, hCG levels are not responsible for failure to recover oocytes. Specifically, there was no correlation between plasma hCG levels and the number of oocytes obtained or other markers of IVF outcome. There was, however, an inverse relationship with BMI, body weight and age.Journal of Assisted Reproduction and Genetics 07/2012; · 1.84 Impact Factor -
Article: Expression and localization of cannabinoid receptors in human immature oocytes and unfertilized metaphase-II oocytes.
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ABSTRACT: Endocannabinoid anandamide and cannabinoid receptors have been described in some organs of the female reproductive system, but little is known about the expression of these receptors in human oocytes. The aim of the study was to describe the expression of cannabinoid receptors in human oocytes and to investigate their differential distribution at various stages of meiotic resumption in human oocytes. A total of 750 human oocytes from 214 patients were analysed by Western blot, immunocytochemistry and PCR. For this study, oocytes that were not suitable for intracytoplasmic sperm injection (ICSI) (germinal-vesicle and metaphase-I stages), as well as metaphase-II oocytes that had not developed into an embryo after ICSI were used. Western blot analysis revealed the presence of CB1 and CB2 receptor proteins in human oocytes. CB1 and CB2 receptor immunostaining patterns changed during the various stages of meiotic resumption. Localization of CB1 receptor was peripheral at germinal-vesicle stage, homogeneous over the entire oocyte at metaphase I and peripheral at mature metaphase II. CB2 receptor localization was peripheral at germinal-vesicle and metaphase-I stages but homogeneous over the entire cell at metaphase II. This finding suggests a possible role for endocannabinoids, acting via receptors, in the maturation of female gametes and fertilization. The number of couples with sterility problems attending fertility programmes is rising but treatment is not always successful. Important problems associated with failure to conceive remain unresolved because many physiological aspects of human reproduction are still unknown. Endocannabinoids are endogenous chemical compounds that mimic the action of the main psychoactive component of marijuana, delta-9-tetrahydrocannabinol. An endogenous cannabinoid named anandamide has been found in human follicular fluid. Thus, in order to develop knowledge in this field, in the present study we have described the presence of the cannabinoid receptors CB1 and CB2 (the proteins required to mediate the action of the cannabinoids) in the early stages of meiotic resumption of oocytes (the stages before ovulation) and we could postulate that the endocannabinoids could act in the regulation of maturation of oocytes. Our study, together with other studies, indicates that the endocannabinoid system may play a role in human reproduction.Reproductive biomedicine online 05/2011; 23(3):372-9. · 2.04 Impact Factor -
Article: Mid-follicular LH supplementation in women aged 35-39 years undergoing ICSI cycles: a randomized controlled study.
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ABSTRACT: This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 mug of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.Reproductive biomedicine online 12/2009; 19(6):879-87. · 2.04 Impact Factor -
Article: Influence of the time interval between embryo catheter loading and discharging on the success of IVF.
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ABSTRACT: To ascertain the influence of the duration of the 'interval loading-discharging embryos' (ILDE) on the results of embryo transfer. The population under study consisted of 450 consecutive fresh embryo transfers. ILDE was measured in all transfers. Pregnancy and implantation rates were analyzed. Conceptional cycles had a lower (mean +/- SD) ILDE than non conceptional cycles (53.5 +/- 43.6 s vs 63.7 +/- 49.3). When only easy transfers--defined as those not requiring cervical tenaculum--were considered, similar differences were observed. The following pregnancy rates were obtained according ILDE duration: 38.9% (ILDE < 30 s), 33.2% (ILDE 31-60), 31.6% (ILDE 61-120) and 19.1% (ILDE > 120) (P < 0.05). When only easy transfers were considered, similar results were obtained: 40.0%, 33.3%, 32.0% and 19.4%, respectively. Similar results were observed regarding implantation rates regarding the whole population (21.2%, 15.4%, 15.9% and 9.4%, respectively; P < 0.01) as well as when only easy transfers were considered. ILDE duration is a prognostic factor of pregnancy rate and of implantation rate in IVF. The longer the ILDE duration, the lower the pregnancy and implantation rates. The decrease in pregnancy and implantation rates is gradual until an ILDE of 120 s, and decreases sharply afterwards. It is recommended to speed up the embryo transfer process, wherever possible. ILDE > 120 s carries a poor prognosis and should, when possible, be avoided.Human Reproduction 09/2004; 19(9):2027-30. · 4.47 Impact Factor -
Article: Ultrasound-guided embryo transfer improves pregnancy rates and increases the frequency of easy transfers.
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ABSTRACT: Recent reports have suggested that ultrasound (US) guidance during embryo transfer might improve pregnancy rates. A prospective randomized (computer-generated random table) trial was performed to compare embryo transfer under abdominal US guidance (n = 255 women) with clinical touch embryo transfer (n = 260). The clinical pregnancy rate was 26.3% (67/255) in the US-guided transfer group compared with 18.1% (47/260) in the clinical touch transfer group (P < 0.05). The implantation rate was 11.1% (100/903) in the US group compared with 7.5% (66/884) in the clinical touch group (P < 0.05). US-guided transfer was associated with a decrease in the difficulty of the transfers: 97% of transfers were easy in the US-guided group compared with 81% in the clinical touch group (P < 0.05). US-guided embryo transfer increased pregnancy and implantation rates in IVF cycles, as well as the frequency of easy transfers. It is suggested that the decrease in cervical and uterine trauma can play a role in the increase in pregnancy rates associated with US-guided transfer. It is recommended that embryo transfer should be performed under US guidance.Human Reproduction 07/2002; 17(7):1762-6. · 4.47 Impact Factor -
Article: Fatty acid composition of fertilization-failed human oocytes.
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ABSTRACT: The aim of the study was to assess the fatty acid composition of human fertilization-failed oocytes. A total of 150 unfertilized oocytes from 43 women undergoing in-vitro fertilization (IVF) were analysed using capillary gas chromatography. The majority of fatty acids were saturated (79.22%), of which stearic (38.65%) and palmitic (32.66%) acids were the most abundant. Of the monounsaturated fatty acids (14.27%) oleic acid was the most abundant (9.77%). Polyunsaturated fatty acids comprised 6.50% of fatty acids, the n-6:n-3 ratio being 7.73. The ratio of eicosapentaenoic acid:docosahexaenoic acid was approximately 5. It is concluded that the most common fatty acids in human unfertilized oocytes are either saturated or monounsaturated fatty acids, whose main function is to provide an energy source. A number of differences in fatty acid composition were observed, in comparison with other biological samples. In particular, stearic and eicosapentaenoic acids were more prominent, and oleic and linoleic acids were less prominent; this may reflect some specific peculiarity of oocyte metabolism.Human Reproduction 09/1998; 13(8):2227-30. · 4.47 Impact Factor -
Article: Sperm morphology analysis (strict criteria) in male infertility is not a prognostic factor in intrauterine insemination with husband's sperm.
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ABSTRACT: To assess the prognostic value of strict sperm morphology analysis in intrauterine insemination with husband's sperm (IUI) cycles performed because of male infertility. Prospective study. Academic tertiary hospital. Seventy-four consecutive couples subjected to 271 IUI cycles because of male infertility. Strict morphology analysis 1 month before the beginning of IUI following the criteria of Kruger et al. Pregnancy and no pregnancy couples were similar regarding strict normal forms (2.85% +/- 2.07% versus 3.13% +/- 2.63%), slightly amorphous forms, and the morphology index (11.79 +/- 6.06 versus 12.04 +/- 7.13). Pregnancy rates (PRs) were similar when normal forms were <4% (39.1%) or > 4% (35.7%). The PR, although higher in the group with morphology index > 10% (41.4%) than in the group < 10% (33.3%), lacked statistical significance. In pure male infertility group, mean values of morphology were similar in pregnancy and nonpregnancy group. A not significant trend was detected toward higher PRs in morphology index > 10% (50.0%) than in the group < 10% (33.3%). Strict morphology analysis 1 month before the beginning of IUI is not a useful prognostic factor in IUI performed because of male infertility.Fertility and Sterility 04/1995; 63(3):608-11. · 3.56 Impact Factor -
Article: Chromosome studies in human unfertilized oocytes and uncleaved zygotes after treatment with gonadotropin-releasing hormone analogs.
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ABSTRACT: To determine the frequency of the anomalies from the cytogenetic point of view in the oocytes remaining from our in vitro fertilization (IVF) program. Two gonadotropin-releasing hormone analogs (GnRH-a) were used (buserelin acetate and leuprolide acetate) in the superovulation treatment. A prospective study was planned in January 1989. Deadline for data and quantitative analysis was to be July 1990. Hospital de Cruces, a public and tertiary institute. One hundred thirty-nine IVF patients, yielding 433 oocytes. Selected on the basis of availability of oocytes and staff. Two hundred thirty-eight oocytes (71.25%) exhibited the normal number of metaphase II chromosomes; 64 (19.16%) exhibited aneuploidy; 13 (3.89%) were diploid, hyperdiploid, or hypodiploid; and 19 (5.68%) showed parthenogenetic activation. Of the 99 zygotes, 17 were polyploid and 48 showed prematurely condensed chromosomes, whereas in 31 cases the male and female pronuclei remained separate. It would not appear that the rate of chromosomal anomalies is affected after pituitary suppression with GnRH-a.Fertility and Sterility 12/1991; 56(5):874-80. · 3.56 Impact Factor -
Article: Deletion of chromosome 4: 46,XY, del(4) (q31.3) after gamete intrafallopian transfer and in vitro fertilization-embryo transfer.
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ABSTRACT: It seems that assisted reproduction technology does not increase the rate of chromosome abnormalities, and up to now, a few cases have been reported. The case we describe here is the first one of monosomy 4q31 in a full-term liveborn after a combined GIFT-IVF procedure. Once more, this case raises the question of whether pregnancies resulting from IVF should be monitored for chromosome abnormalities or not.Fertility and Sterility 12/1990; 54(5):953-4. · 3.56 Impact Factor -
Article: Total immunoreactive alpha-inhibin in human seminal plasma, sperm quality, and in vitro fertilization rates.
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ABSTRACT: To assess the relationship between the concentrations of total immunoreactive alpha-inhibin in human seminal plasma, sperm quality, and in vitro fertilization (IVF) rates. Medical school hospital. Prospective study. 72 consecutive couples undergoing IVF with husband's sperm in which at least 4 oocytes were obtained. Alpha-inhibin determination by means of enzyme-linked immunosorbent assay, sperm analysis for density and motility, IVF rates. Total immunoreactive alpha-inhibin levels were not correlated with IVF rates. Nor were there any differences in fertilization rates in the different groups. Lower inhibin levels were found in oligozoospermic cases. Lower sperm counts were found in cases with inhibin values below the median value, and also with respect to various other cutoffs. No correlation was found between inhibin levels and any of the sperm variables measured. Total immunoreactive alpha-inhibin is not a prognostic factor in IVF cycles. However, an association was found between inhibin and sperm concentration, suggesting that alpha-inhibin in the human seminal fluid could be a marker for some aspects of spermatogenesis.International journal of fertility and women's medicine 43(3):171-6. · 0.56 Impact Factor -
Article: Fatty acid composition of fertilization-failed human oocytes
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Institutions
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1998–2004
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Hospital de Cruces
Bilbao, Basque Country, Spain
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