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L Blasco

Publications and source records attributed to L Blasco.

At least 37 records · Page 2Linked to original sources

Relationships between polypronuclear fertilization and follicular fluid hormones in gonadotropin-treated women.

Similar incidences of congenital abnormalities in in vitro fertilization and embryo transfer (IVF-ET) pregnancies and births in the general population have not supported earlier concerns that IVF may increase chromosomal aberrations. Nevertheless, polypronuclear fertilization is a common, undesirable, and poorly understood outcome of IVF. We evaluated hormone levels in 20 follicular fluids that were associated with mature oocytes that have fertilized abnormally (greater than or equal to pronuclei) and compared them to follicles with mature oocytes that cleaved normally, fertilized but failed to cleave, or did not fertilize. Progesterone (P), androstenedione, estradiol, percent free estradiol, sex hormone-binding globulin, insulin, and prolactin were measured. P levels were significantly higher in follicular fluids associated with oocytes that fertilized abnormally than in the other groups. Levels of the other hormones were similar in all the study groups. We conclude that IVF of oocytes from highly luteinized follicles as judged by P levels may result in polypronuclear fertilization.

Body Fluids↗

Capacitation and acrosome reactions in human spermatozoa monitored by a chlortetracycline fluorescence assay.

Human spermatozoa were incubated in culture medium containing human serum albumin (HSA) to promote capacitation, which was monitored by a rapid chlortetracycline (CTC) fluorescence assay. Four CTC fluorescence patterns were readily distinguished, one of which appeared to be correlated with capacitated sperm. When capacitated sperm were treated with either ionophore A23187 or acid-solubilized mouse zonae pellucidae to induce the acrosome reaction, the CTC assay identified acrosome-reacted sperm by lack of fluorescence on the head. Fresh sperm would not undergo the induced acrosome reaction. The percentages of acrosome-reacted sperm identified by the CTC assay in induced and control populations were the same as those identified by the presently used indirect immunofluorescence and triple stain assays.

Acrosome↗

Dose of human menopausal gonadotropin influences the outcome of an in vitro fertilization program.

This study compares outcomes of in vitro fertilization (IVF) in two groups of 57 patients when either 2 (group 1) or 3 (group 2) ampules of human menopausal gonadotropin (hMG) were administered daily. Treatment began on day 3 of the cycle and was discontinued when at least 2 follicles attained diameters greater than or equal to 1.5 cm. Human chorionic gonadotropin (hCG) was given either 24 or 48 hours after the last dose of hMG. Although serum estradiol levels were lower in group 1, the average number of oocytes retrieved (3.2 versus 2.9), fertilized (1.9 versus 2.0), and cleaved (1.7 versus 1.8) per completed cycle did not differ between groups 1 and 2. Likewise, the number of oocytes that fertilized abnormally was similar in both groups (0.5 versus 0.3/cycle). However, the number of atretic oocytes (0.03 versus 0.5/cycle) and the percent of oocytes recovered from the cul-de-sac (0 versus 7.2%) were significantly (P less than 0.05) lower in group 1. In group 1, administration of hCG 48 hours after the last dose of hMG was associated with a higher number of cleaving embryos (2.1 versus 1.5/cycle) and a higher pregnancy rate (34.8 versus 14.7%; P less than 0.05) when compared with injection at 24 hours. In group 2, the interval between hMG and hCG did not influence these results. Together, the associations between fewer oocytes that were atretic or recovered from the cul-de-sac, and a trend toward a higher pregnancy rate, suggest that follicular recruitment with 2 ampules of hMG is more appropriate than 3 ampules in an IVF program.

Chorionic Gonadotropin↗

Endometrial cytosolic and nuclear progesterone receptors in the luteal phase defect.

Basal body temperature profiles, serial serum progesterone levels, and serial endometrial biopsies were studied in 15 infertile women during 21 ovulatory cycles. Ten cycles (in 9 women) demonstrated luteal phase defects (LPD), diagnosed by a histological lag in endometrial maturation, normal luteal phase length, and normal luteal phase serum progesterone levels. Both normal and LPD cycles had a maximum amount of endometrial cytosolic progesterone receptor (PgR) on days 13-15, with a significant decline thereafter. LPD cycles had significantly lower endometrial nuclear PgR concentrations than did normal cycles during the proliferative phase, but luteal phase endometrial nuclear PgR levels were similar in both groups. In 2 LPD women treated with dydrogesterone, normal endometrial maturation and a decline in endometrial cytosolic PgR concentrations in the late luteal phase were found. Therefore, with the exception of endometrial nuclear PgR concentrations during the proliferative phase, we found no evidence for a major abnormality in endometrial PgR levels in LPD cycles with a lag in endometrial histology.

Adult↗

Cervical mucus changes in relationship to urinary luteinizing hormone.

In order to evaluate the relationship between the urinary luteinizing hormone (LH) surge as detected by the OvuSTICK (Monoclonal Antibodies, Inc., Mountain View, CA) method and daily cervical mucus parameters, ten spontaneously ovulating women undergoing infertility evaluation were followed during their cycles with twice daily urinary LH testing as well as daily ultrasound, mucus evaluation, and hormonal assays of serum LH, progesterone (P), and estradiol (E2). Maximal cervical mucus scores, as determined using a modified Insler score, were noted to coincide consistently with the urinary LH surge as detected by twice daily testing and to precede ultrasound evidence of ovulation by 0 to 24 hours. Mucus scores rapidly declined in the 24-hour period following the urinary LH surge. Detection of the urinary LH surge may therefore help identify that period of time during which cervical mucus parameters are optimal and therefore facilitate the timing of artificial insemination, intercourse, or postcoital testing.

Cervix Mucus↗

Follicular maturation parameters associated with the failure of oocyte retrieval, fertilization, and cleavage in vitro.

Follicular maturation parameters predictive of decreased success in human in vitro fertilization were evaluated in 104 gonadotropin-stimulated cycles. Falling estradiol (E2) levels correlated with decreased fertilization (1.9 oocyte/cycle) and cleavage (1.4 oocyte/cycle), when compared with cycles with increasing E2 (2.4 and 2.1 oocyte/cycle, respectively). Likewise, polyspermic fertilization was higher in the former group. Falling E2 levels after human chorionic gonadotropin (hCG) administration correlated with similar trends. Delaying hCG (24 to 96 hours) relative to the last dose of gonadotropin did not affect the total number of oocytes fertilized per cycle. However, polyspermic fertilization and cancellation rates were higher. Leading follicles growing beyond 2.3 cm (determined by ultrasound examination) were associated with decreased recovery, fertilization, and cleavage, and increased polyspermic fertilization. We conclude that ultrasonography and E2 monitoring can predict decreased fertilization and cleavage and should also be monitored after hCG administration.

Chorionic Gonadotropin↗

Fertilization and cleavage after reinsemination of human oocytes in vitro.

The results of reinsemination of 150 morphologically mature oocytes that failed to fertilize within 15 to 20 hours after initial insemination were evaluated. Only 41 oocytes (27.3%) were fertilized after reinsemination, which is significantly lower than the percentage obtained after initial insemination (74%). However, the cleavage rate was not impaired significantly. Polyspermic fertilization was common (17 oocytes, 29.3%). A total of 64 oocytes were transferred. In 18 patients, all of the oocytes that were transferred had been reinseminated; none of these patients conceived. However, of 28 patients who received embryos arising from both initial insemination and reinsemination protocols, 7 conceived (25%). We suggest that the percentage of fertilization is impaired after 22 hours of incubation in vitro and that those oocytes that have fertilized after reinsemination might partly reflect a misjudgment of initial oocyte maturity. Nevertheless, reinsemination is a relatively simple procedure, with no known attributed risk. Therefore, we recommend reinsemination to increase the overall fertilization percentage. Additional studies are needed to establish better methods for assessment of oocyte maturity to evaluate properly the benefit of such reinsemination procedures.

Cleavage Stage, Ovum↗

Comparison of ultrasonographic transurethral and laparoscopic guided oocytes retrieval.

Fifty-eight patients who underwent in vitro fertilization (IVF) treatment were divided into two groups. In 28 patients, ultrasonically guided transurethral follicular aspiration was performed under light general anesthesia. In 30 patients, laparoscopic follicular aspiration was performed under general anesthesia. The mean age for both groups was similar. Follicular recruitment was achieved with human menopausal gonadotropin (hMG) or a combination of clomiphene citrate and hMG. In the ultrasonically guided aspiration group, 128 follicles were aspirated, with a 64% recovery rate (83 oocytes) and an 88.1% embryo transfer (ET) rate (67 embryos). Three (10.7%) intrauterine pregnancies were established in this group. In the laparoscopic group, 153 follicles were aspirated, with a 68.6% recovery rate (105 oocytes) and an 86.3% ET rate (82 embryos), with 4 (13.3%) intrauterine pregnancies established. Three patients had both procedures done; however, none conceived. There were no statistically significant differences between the two groups. Ultrasonically guided transurethral follicular aspiration should be considered as an alternative route for oocyte retrieval, especially when laparoscopy is contraindicated or when the ovaries are not accessible.

Female↗

Polycystic ovaries: MR imaging.

To determine the characteristic appearance of polycystic ovaries on magnetic resonance (MR) images, seven women with polycystic ovarian disease (PCOD) underwent MR examination of the pelvis. These MR images were compared with sonograms. Histologic material was available in two patients. Six of the seven women had characteristic, small peripheral cysts, best seen on T2-weighted MR images; these cysts were seen sonographically in only one case. The centers of nine of 14 ovaries were of low intensity with all MR pulse sequences; this low intensity corresponded with low echogenicity in six cases. Histologically, these areas correlated with hypertrophic cellular stroma. Coexisting central teratomas were seen in three ovaries. The ability of MR to display the findings of PCOD better than ultrasound and its ability to demonstrate coexisting pathologic conditions are valuable in imaging the female pelvis.

Adult↗

Sonographic assessment of the endometrium in patients undergoing in vitro fertilization.

Sonography has an important role in the care of infertile patients undergoing in vitro fertilization. Unlike the ovarian follicle, sonographic changes in the endometrium during induction have not been extensively investigated. To determine whether changes in endometrial thickness or changes in endometrial texture would predict subsequent pregnancy, a randomized, double-blind review of 320 studies was performed. None of the endometrial patterns nor any particular change from one pattern to another during induction was predictive of subsequent pregnancy. Although differences in endometrial thickness between non-pregnant and subsequently pregnant patients were noted, on an individual basis, endometrial thickness was not a useful predictor.

Double-Blind Method↗

Simultaneous ectopic pregnancy with intrauterine twin gestations after in vitro fertilization and embryo transfer.

A simultaneous ectopic tubal pregnancy with viable intrauterine twin gestations after IVF-ET of five fertilized eggs is presented. Pelvic ultrasound and serial quantitative hCG levels were not helpful in the diagnosis of the tubal pregnancy. The risk of multiple pregnancies and of concomitant intrauterine and extrauterine gestations increases with transfer of a greater number of embryos. Karyotype of the tubal pregnancy was normal (46,XX).

Adult↗

The zona-free hamster egg penetration assay as a prognostic indicator in a human in vitro fertilization program.

The present study was designed to test the validity of the hamster egg penetration assay as a prognostic indicator of male fertility in 54 patients undergoing in vitro fertilization. Human oocyte fertilization, cleavage, and pregnancy were compared with the results of this bioassay. Good correlation was found between hamster egg penetration and oocyte fertilization. Conversely, a definite lower limit of hamster egg penetration to define absolute male infertility could not be established because human oocyte fertilization, cleavage, and even pregnancy occurred in spite of low hamster egg penetration.

Animals↗

Detection of the ovulatory luteinizing hormone (LH) surge with a semiquantitative urinary LH assay.

We examined blood concentrations of ovarian steroid hormones (E2, P) and serum LH concentrations to establish that the Ovu-STICK assay reliably reflects endocrine events in the periovulatory period. In all 16 cycles studied, which included 2 cycles in which the women received CC, the ovulatory surge of LH was detected with the use of the Ovu-STICK assay. In contrast, BBT monitoring correctly predicted the ovulatory event in only half the cycles.

Clomiphene↗

The effect of immunoglobulin occurring on human sperm in vivo on the human sperm/hamster ova penetration assay.

We selected 91 infertile men who were tested for increased sperm-associated immunoglobulin and also tested in the human sperm/hamster ova penetration assay. There was a statistically significant association between the presence of increased sperm-associated IgG alone (p = 0.0218) and both sperm-associated IgG and A (p = 0.0187) when correlated with the failure to penetrate any hamster ova. There was a trend but no statistical significance when sperm-associated immunoglobulin A alone was present. There was a trend but no statistical relationship between the presence of sperm-associated immunoglobulin and the sperm penetration assay when the criteria for normality of the sperm penetration assay was a 15% or greater ovum penetration rate.

Animals↗

Serum hormones and their receptors in women with normal and inadequate corpus luteum function.

The purpose of this study was to attempt to characterize women with a luteal phase defect (LPD) by cytosol estrogen and progesterone (P) levels and peroxidase activity in endometrial biopsy samples. These values were correlated with circulating serum estradiol, P, testosterone, and dehydroepiandrosterone sulfate measurements. Similar data were obtained from women during the proliferative phase of the cycle. Midluteal phase P values were significantly greater in women with normal luteal function than in those with LPD; however, some overlap of values existed. Furthermore, because no significant differences between this group and normal women were seen, we were unable to characterize women with LPD by estrogen or P receptor levels or endometrial peroxidase activity.

Corpus Luteum↗

Human sperm velocity and postinsemination cervical mucus test in the evaluation of the infertile couple.

Homologous artificial insemination (AIH) followed by postinsemination cervical mucus test (PIT) was performed in 100 couples in a prospective study to evaluate suspected cervical or male factor infertility. A portion of the ejaculate was submitted for standard semen analysis as well as turbidimetric analysis of sperm velocity. In a review of 333 cases evaluated for infertility, the average sperm velocity in a normal semen analysis was 96.5 mu/sec, for those with normal postcoital test (PCT) 96.6 mu/sec, and in those that established a pregnancy 91.6 mu/sec. These are significantly higher than the values obtained for abnormal semen analysis and abnormal PCT (64.6 and 63.6 mu/sec, respectively; p less than 0.001). Patients with normal PIT (WHO criteria for normal PCT consisting of greater than or equal to 7 motile sperm/hpf) had sperm velocity of 87 mu/sec compared to velocities of 46 mu/sec for abnormal PIT (p less than 0.001). Four of the five patients with abnormal PIT (in spite of normal semen analysis and normal cervical mucus) had sperm velocities less than 75 mu/sec. Likewise, all 8 patients who had normal PIT in spite of abnormal semen analysis had sperm velocities greater than 75 mu/sec, even though the sperm motility was below normal in 5 of them. Sperm velocity is a more sensitive indicator of sperm function when compared to standard semen analysis results.

Cervix Mucus↗