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L Blasco

Publications and source records attributed to L Blasco.

At least 19 recordsLinked to original sources
PubMed2000

Impact of stage III-IV endometriosis on recipients of sibling oocytes: matched case-control study.

OBJECTIVE: To evaluate the impact of severe endometriosis on IVF-ET outcome in women receiving oocytes from the-same donor. DESIGN: A matched case-control study. SETTING: Oocyte donation program at the Instituto Valenciano de Infertilidad. PATIENT(S): Fifty-eight recipients were included in a matched case-control study of IVF-ET in our oocyte donation program. Twenty-five patients were diagnosed by laparoscopy with stage III-IV endometriosis (group I), while the remaining 33 were free of the disease (group II). On the day of retrieval, oocytes from a single donor were donated to recipients from both groups. Some of the donors supplied oocytes for more than 2 patients. Recipients received steroid replacement therapy for endometrial preparation. INTERVENTION(S): Ovarian stimulation and oocyte retrieval in donors. Uterine embryo transfer (ET) in recipients after appropriate exogenous hormone replacement therapy (HRT). MAIN OUTCOME MEASURE(S): Pregnancy, implantation, miscarriage, and live birth rates. RESULT(S): The number of oocytes donated and fertilized, as well as the number of available and transferred embryos, was not statistically different between the two groups. Pregnancy, implantation, and miscarriage rates were not affected by stage III-IV endometriosis when compared with the control group. The live birth rate was 28.0% in the group with endometriosis and 27.2% in the control group. CONCLUSION(S): These results show that implantation is not affected by stage III-IV endometriosis. Given the contemporary methods of endometrial preparation for transfer of embryos derived from donor oocytes, any potential negative effect of severe endometriosis on the uterine environment is undetectable.

Abortion, Spontaneous↗
PubMed2000

Embryo reduction of multifetal pregnancies following assisted reproduction treatment: a modification of the transvaginal ultrasound-guided technique.

First-trimester transvaginal embryo reduction is an effective alternative for the management of multifetal pregnancy in assisted reproduction. We have modified the transvaginal technique by performing an intracardiac embryo puncture until asystolia is verified, without the injection of any substances. Any aspiration of embryo tissues or amniotic fluid was avoided. A total of 149 multifetal pregnancies was reduced to twins (n = 134) or singletons (n = 15) at early gestational age (7.8 +/- 0.8 weeks). Eleven cases (7.3%) of miscarriage, two cases (1.3%) of chorioamnionitis, and 17 cases (11.4%) of transient spotting were recorded as postoperative complications. Vanishing of one embryo occurred in four cases (3.0%) of those reduced to twins. The baby take-home rate was 89.5% for twins and 80.0% for singletons. Pregnancy outcome was analysed and compared with a control group of women with non-reduced multiple pregnancies. The birth weight of singleton pregnancies after reduction was lower (2929 +/- 160 versus 3291 +/- 422 g; P < 0.02). These studies show that early transvaginal intracardiac embryo puncture is an effective and safe technique.

Adult↗
PubMed1997

Nocturnal hypoglycaemia in IDDM patients younger than 18 years.

The present multicentre study was undertaken to assess the prevalence of nocturnal hypoglycaemia and its determining factors in 117 diabetic children and adolescents, aged 2-18 years and diabetes duration > 1 year in Spain. Each child made 3 measurements of blood glucose (BG) at home at night (between 0000 h and 0600 h) on nine separate nights. A hypoglycaemic event occurred in 12-14% of children in any one night. This is lower than rates for nocturnal hypoglycaemia reported in literature, perhaps because of relatively late mealtimes and different meal content, in Spanish children. Children aged < 7 years were at higher risk of nocturnal hypoglycaemia than older children (p < 0.05). Mean HbA1c from the year before the study and mean HbA1c measured during the closest time to the study were significantly lower in those with nocturnal hypoglycaemia (p < 0.0001). Blood glucose concentrations 2 h before hypoglycaemia did not predict nocturnal hypoglycaemia. The occurrence of low or very low blood glucose concentrations before breakfast was related to a higher risk for nocturnal hypoglycaemia (chi 2 22.97; p < 0.001). No previous symptoms were detectable in 89% of cases.

Adolescent↗
PubMed1996

A comparison of three methods for detecting the acrosome reaction in human spermatozoa.

This study was designed to compare three different fluorescent probes to assay the acrosome reaction in human spermatozoa: chlortetracycline (CTC), mannosylated bovine serum albumin (BSA) labelled with fluorescein (MAF), and quinacrine (QN). Normal human sperm ejaculates were washed and allowed to swim up for 30-60 min. Samples were examined under epifluorescence for the percentage of the acrosome reacted spermatozoa, as detected by the three probes. There was no significant differences between samples of fresh, uncapacitated spermatozoa evaluated with CTC, MAF or QN; all gave < 10% reacted. Following capacitation for 3 h, the percentage of spontaneously reacted spermatozoa was higher than in fresh spermatozoa; CTC and MAF gave the same percentage (12%), while QN indicated a higher percentage (18%) of reacted spermatozoa (P < 0.001). Following exposure to ionophore A23187 at 1 h, the percentage of acrosome reactions increased to a mean of 31% as detected with CTC or MAF; the mean percentage (45%) was significantly higher with QN (P < 0.0001). Further incubation up to 2 h with A23187 did not change these percentages. These results suggest that the QN probe detects the onset stage of the acrosome reaction, whereas the CTC and MAF probes detect the later stages in which the acrosomal cap is lost. Use of the two types of probe provides a means for finer resolution of the time course of the acrosome reaction in the human spermatozoa.

Acrosome↗
PubMed1995

Can the immunobead assay for detecting sperm antibodies in fresh samples be reproduced in cryopreserved/thawed human spermatozoa?

PROBLEM: To evaluate the reproducibility of the Immunobead Assay (IBA) on sperm samples before and after cryopreservation. METHOD: Sperm samples (fresh and post-thaw) from known antibody negative donors (N = 20) were evaluated for percent immunobead binding by IBA following incubation with known antibody-positive serum. RESULTS: In both fresh and thawed negative samples, the mean sperm head binding was 0.5% +/- 0.5, the mean sperm tail binding was 2.0% +/- 2.0 and the mean sperm head-tail binding was 3.0% +/- 2.0 for IgG, IgA and IgM type antibodies, respectively. The same samples exposed to positive sera showed 40.0% +/- 10.0 mean head binding, 7.0% +/- 8.0 mean tail binding and 47.0% +/- 11.0 mean head-tail binding. CONCLUSIONS: IBA is highly reproducible for detecting sperm antibodies in both fresh and cryopreserved/thawed samples of human spermatozoa.

Autoantibodies↗
PubMed1994

Effect of follicular size on oocyte retrieval, fertilization, cleavage, and embryo quality in in vitro fertilization cycles: a 6-year data collection.

OBJECTIVE: To determine the effect of follicular size, including the size of the leading follicle, on oocyte retrieval, fertilization, cleavage, and embryo quality in IVF cycles based on a large data collection. DESIGN: Retrospective analysis of 1,109 IVF cycles between 1987 and 1993 at the Hospital of the University of Pennsylvania including 606 patients ranging in age from 23 to 49 years. RESULTS: Follicles with a volume < or = 1 mL show a significantly lower oocyte recovery rate than follicles with a volume of > 1 mL. The highest recovery rate (83.5%) was found in follicles with a volume of 3 to 4 mL. Above a follicular volume of 7 mL, the oocyte recovery drops below that observed for follicles between 1 and 7 mL. Fertilization and cleavage rates were also higher in oocytes obtained from follicles > 1 mL compared with follicles < or = 1 mL. Although fertilization rates were fairly stable above volumes of 1 mL, cleavage rates continued to rise to a peak percentage of 92% with volumes between 6 and 7 mL. Leading follicle size did not have an effect on fertilization and cleavage rates of cohort oocytes. Embryo quality was not influenced significantly by follicular volume. CONCLUSION: Based on this evaluation of a large number of follicles, follicular size is a useful indicator of oocyte recovery, fertilization, and cleavage in IVF cycles. For optimal results, the follicular fluid volume in gonadotropin- and hCG-stimulated cycles should be > 1 mL, which corresponds to a follicle diameter of > 12 mm, and not larger than 7 mL (24 mm). For timing of hCG administration, the number of adequate size follicles appears to be more important than the size of the leading follicle(s).

Adult↗
PubMed1993

Centrifugation of human spermatozoa induces sublethal damage; separation of human spermatozoa from seminal plasma by a dextran swim-up procedure without centrifugation extends their motile lifetime.

While washing of human sperm cells by centrifugation and resuspension is a procedure in widespread use, there have been indications that this procedure per se may be harmful to the cells. The objective of this study was to investigate this question. To this end, a method for the clean separation of motile human spermatozoa from seminal plasma in the absence of centrifugation was developed, using a modified swim-up procedure, in which liquefied semen was mixed with an equal volume of 30 mg/ml dextran in medium, and the mixture overlaid with medium containing 5 mg/ml bovine serum albumin, forming two discreet layers with stable interface. The percentage of motile cells in a given sample was consistently > 80% immediately after recovery. Damage to the cells was assessed by loss of motile cells during incubation up to 96 h post-recovery. Comparison of aliquots of spermatozoa obtained by the dextran swim-up procedure showed that the aliquot subjected to centrifugation had 4 +/- 3% motile cells after 48 h, while the untreated aliquot had 52 +/- 12%. The aliquots showed no difference 1 h post-recovery. Similar results were obtained with spermatozoa that had been centrifuged in seminal plasma and resuspended in fresh plasma, then recovered by dextran swim-up. The delayed onset of motility loss in the centrifuged samples implies that this treatment induces sublethal damage in the cells. Comparison of the standard swim-up and Percoll gradient methods for sperm recovery, both of which involve centrifugation steps, showed decline in motility of the samples similar to that seen with dextran swim-up of centrifuged cells. We conclude that centrifugation per se induces sublethal damage in human spermatozoa, independently of treatment method, and suggest that recovery methods for human spermatozoa which avoid centrifugation might partially alleviate the damage incurred by these cells during cryopreservation.

Adult↗
PubMed1993

Perioperative complications arising after transvaginal oocyte retrieval.

OBJECTIVE: To determine the incidence of perioperative morbidity in patients undergoing transvaginal oocyte retrieval and to identify those patients at greatest risk for complications. METHODS: A retrospective analysis was performed on 674 patients of reproductive age who underwent transvaginal retrieval of oocytes for assisted reproduction technologies during a 3-year period. All procedures were performed by surgeons with extensive experience with transvaginal retrieval. Patients were entered into the program with a primary diagnosis of unexplained infertility (16%), endometriosis (32%), pelvic adhesions and/or tubal occlusion (38%), or infertility from male or immunologic factors (14%). RESULTS: Of the 674 patients studied, ten (1.5%) required hospital admission because of perioperative complications. Nine of these patients needed intravenous antibiotics and one required admission and observation for an expanding broad-ligament hematoma. Six of nine women admitted for antibiotic therapy had a history of extensive pelvic adhesions with or without a history of salpingitis. Five of nine patients had a history of salpingitis. In addition, two patients experienced impressive vaginal arterial bleeding during the procedure. CONCLUSION: This study suggests that transvaginal retrieval may not be as innocuous as is often expressed and that the primary factor predisposing to perioperative morbidity is a history of previous pelvic inflammatory disease and/or adnexal adhesions.

Adult↗
PubMed1990

Comparison of different regimens of a gonadotropin-releasing hormone analog during ovarian stimulation for in vitro fertilization.

Three treatment protocols were used in 156 in vitro fertilization cycles. Leuprolide acetate was begun on day 1 of the cycle in one group (n = 20), on day 3 in another (n = 48), and the third control group (n = 88) did not receive the gonadotropin-releasing hormone analog. Human menopausal gonadotropin was initiated on day 3 in all groups. Peak estradiol (E2) levels and the mean numbers of mature oocytes and embryos transferred per cycle were significantly greater in the day 3 group than in either the day 1 or control groups. Patients who received the day 3 protocol had significantly fewer cancelled cycles. A decline in E2 was observed on the third day of analog administration in certain patients, particularly those on the day 1 protocol. Follicle-stimulating hormone and luteinizing hormone (LH) levels increased two- to fivefold 24 hours after initiation of the analog. Thereafter the gonadotropin levels fell, but nevertheless remained above those of controls for most of the cycle. Hence, it appears that enhanced follicular growth attributed to the early transient rises in gonadotropins can be coupled to a suppression of endogenous LH surges in leuprolide-treated women. These beneficial effects seem to be more likely to occur if leuprolide is initiated on cycle day 3 rather than day 1.

Adult↗
PubMed1989

Repetitive ovarian response to gonadotropin stimulation in an in vitro fertilization program.

The temporal changes of estradiol levels in 19 women undergoing ovulation induction for in vitro fertilization (IVF) and embryo replacement were described by a mathematical model. The model was analyzed for differences between treatment cycles of an individual woman and between cycles of different women. This model was also used to evaluate the results of IVF treatment. The variation between cycles within individuals was found to be less than that between different women. The parameters that describe this model were found to correlate with follicular growth but not with number of oocytes retrieved, fertilized or cleaved.

Adult↗
PubMed1989

Ovulation prediction by monitoring salivary and vaginal electrical resistance with the PEAK Ovulation Predictor.

We investigated the ability of the PEAK Ovulation Predictor to predict the expected date of ovulation in 21 infertile, spontaneously ovulating women. A nonsignificant correlation (R = 0.15; P = .51) existed between the predicted date of ovulation and the day of the serum LH peak. A moderately strong correlation (R = 0.61; P less than .01) was observed between the day of the salivary electrical resistance peak and that of the serum LH peak. However, the serum LH peak occurred between 4-9 days after an identified peak in salivary electrical resistance. Twice-daily urine LH testing correlated strongly with both the serum LH peak (R = 0.93; P = .0001) and the ultrasound-detected day of ovulation (R = 0.81; P = .0001). A statistically significant peak in the mean salivary or vaginal electrical resistance on a particular day relative to the day of the serum LH peak could not be demonstrated. When identified, the nadir in vaginal electrical resistance occurred no earlier than 2 days before the serum LH peak and thus may mark the endpoint of the fertile period for natural family planning methods. We conclude that, whereas the PEAK Ovulation Predictor is of little value in accurately predicting ovulation, measurements of salivary and vaginal electrical resistance may be helpful in timing inseminations. However, for detection of the serum LH surge, twice-daily urine LH testing demonstrated a stronger correlation and narrower frequency distribution than did those determinations based on electrical resistance.

Adult↗
PubMed1988

Follicular aspiration and in vitro fertilization associated with pelvic reconstructive surgery.

Between August 1982 and May 1987, 103 patients underwent in vitro fertilization-embryo transfer (IVF-ET) in association with pelvic reconstructive surgery for infertility. Follicular stimulation was induced with clomiphene citrate and laparotomy scheduled day 12 to 15 of the menstrual cycle. Ultrasound measurements of follicular diameter and number of follicles were obtained on the day of human chorionic gonadotropin (hCG) administration, and laparotomy and ovum retrieval performed 36 hours later. Embryo transfer was performed 48 to 72 hours after insemination. Patients were treated postoperatively with intramuscular progesterone. In addition to evaluating the overall pregnancy rate, the outcome of patients having one or more follicles greater than or equal to 1.4 cm in mean diameter (group A) were compared to those in group B (no follicles greater than or equal to 1.4 cm in diameter). The number of oocytes obtained and the fertilization rate and polyspermic fertilization rate were not significantly different between groups; 10.1% of patients in group A conceived but no patient conceived in group B, yielding an overall pregnancy rate of 8.7%. These data suggest that physicians having IVF-ET at their disposal offer patients IVF during pelvic reconstructive surgery.

Adult↗
PubMed1988

An increased initial follicle-stimulating hormone/luteinizing hormone ratio does not affect ovarian responses and the outcomes of in vitro fertilization.

The tenet that a combination of human follicle-stimulating hormone (hFSH)/human menopausal gonadotropin (hMG) improves follicular recruitment was assessed by randomly treating ovulatory women either with hFSH/hMG on days 3 and 4 of the cycle followed by two ampules of hMG daily or with a constant daily dose of 2 ampules of hMG. Estradiol (E2) levels on the day of human chorionic gonadotropin (hCG) and the mean number of mature, immature and atretic oocytes per cycle did not differ between the two groups. Likewise, fertilization, cleavage, and pregnancy rates were similar for the two treatments. When daily hormone levels were compared in 11 patients during two successive treatment cycles with both stimulation protocols, the temporal pattern of FSH accumulation was repeated in both cycles, but FSH levels were significantly higher when patients received hFSH/hMG. Nevertheless, during both cycles, E2 reached similar peak levels and the mean number of follicles per cycle on the day of hCG administration was not different. We conclude that routine use of hFSH/hMG does not improve the success of an in vitro fertilization (IVF) program and that higher FSH levels do not change the individuality of ovarian response in the same woman.

Estradiol↗
PubMed1988

Incidence of abortion in pregnancies after in vitro fertilization and embryo transfer.

Our purpose was to assess factors that are associated with an increased rate of spontaneous abortion in pregnancies initiated by in vitro fertilization. Pregnancies were diagnosed by measurement of serum human chorionic gonadotropin (hCG) 15 days after embryo transfer. Of the 64 women who conceived, 47 delivered term infants, one patient delivered a stillborn at 22 weeks, 14 aborted in the first trimester, and two had pregnancies that implanted in the tube. Abortion rates were similar for women treated with human menopausal gonadotropin (24%; 12 of 54) and those who received clomiphene citrate (12.5%; one of eight). Two patients conceived after treatment with a combination of clomiphene citrate and human menopausal gonadotropin, neither of whom aborted. In 54 patients treated with human menopausal gonadotropin, there were no significant differences in mean maternal age, number of years of infertility before the pregnancy, history of previous pregnancies, amount of human menopausal gonadotropin used to induce ovulation, serum estradiol levels on the day of hCG administration, mean number of follicles, and the mean number of transferred embryos between the group who delivered and the group who aborted. We conclude that none of these factors are associated with increased tendency for fetal loss in our in vitro fertilization program. Beta-hCG levels on day 15 after embryo transfer were significantly lower in the group who aborted than in the group who delivered, and may be predictive of implantation failure.

Abortion, Spontaneous↗
PubMed1988

Ovarian response to human menopausal gonadotropin following suppression with oral contraceptives.

The main conclusion of this study is that a profound suppression of the pituitary and ovary can be associated with an inadequate response which may require a longer or different regimen of stimulation to achieve the desired outcome for IVF. We suggest that a pretreatment determination of E2 and gonadotropins can be of value to predict the nature of ovarian response in women with suppressed pituitary-ovarian function.

Contraceptives, Oral↗