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Biomedical subjects

L L Veeck

Publications and source records attributed to L L Veeck.

At least 73 records · Page 4Linked to original sources
PubMed1989

Critical assessment of sperm morphology before and after double wash swim-up preparation for in vitro fertilization.

Critical assessment of sperm morphology using specific and stringent criteria is predictive of the subsequent ability of those sperm to fertilize oocytes in in vitro fertilization (IVF). Previous studies have evaluated sperm morphology prior to sperm preparation and, thus, have not assessed the actual sperm used for insemination. We studied the impact of a double wash swim-up technique used for IVF on sperm morphology using the strict criteria of Kruger et al. [5, 6] in 73 consecutive patients undergoing IVF. Pre- and postswim-up morphological assessments were done in a prospective, randomized, and blinded fashion. The mean percentage of normal forms pre- and postswim-up was 19.8% and 23.4%, respectively, an improvement of 18% (p less than 0.05) with 62 of 73 patients showing improvement. Significantly, analysis of the 27 patients with abnormal morphology on initial assessment (normal forms less than or equal to 14%) revealed an improvement in percentage of normal forms from 9.0% to 21.5%, a mean increase of 239% (p less than 0.005). Eighteen of these 27 patients showed improvement in their percentage of normal forms, eight were unchanged, and only one patient had a decline in their percentage of normal forms. We conclude that the double wash swim-up preparation used for IVF substantially improves the percentage of sperm with normal morphology, and that the benefit is most substantial in those cases where the percentage of normal morphology is abnormal.

Fertilization in Vitro↗
PubMed1988

Failure of fertilization in in vitro fertilization: the "occult" male factor.

Failure of fertilization in patients undergoing in vitro fertilization (IVF) deserves extensive analysis for better prediction of the success or failure of this therapeutic modality. Consequently, we retrospectively studied the 52 couples in whom fertilization failed during Norfolk series 18 to 25, in an effort to establish the precise causes of failure. In the initial evaluation, pure oocyte abnormalities were identified in 19.2% of the cases; 32.6% showed sperm abnormalities, and a combination of oocyte and sperm anomalies was found in 7.7%. In 40.4% of the cases, failure of fertilization could not be explained. Reassessment of sperm morphology by new, strict criteria increased the identification of sperm abnormalities to 61.5% and of combined sperm and oocyte anomalies to 13.4%, for a total of 74.9% of sperm factors involved, as opposed to 40.3% in the original evaluation. The incidence of unexplained failed fertilization was substantially reduced, to 11.5%. In a control group (tubal infertility) matched by age, date, and stimulation, in whom fertilization occurred, 83.3% had normal sperm parameters as judged by the new criteria for morphology evaluation. This paper emphasizes the need for a more accurate diagnosis of sperm abnormalities to establish the true incidence of this factor in failed fertilization and to obtain information of prognostic value to patients and clinicians.

Adult↗
PubMed1988

Significance of the recovery of fractured-zona oocytes in an in vitro fertilization program.

Recovery of fractured-zona oocytes (FZOs) from patients undergoing in vitro fertilization and embryo transfer (IVF/ET) has been previously reported. The present study was undertaken to determine the possible influence of different stimulation protocols and retrieval techniques on the incidence of FZOs, to analyze possible causes, and to evaluate the significance of FZOs in terms of IVF/ET results. Four hundred thirty-three cycles in which one or more FZOs were recovered (fractured-zona cycles; FZCs) and 1114 cycles in which FZOs were not obtained (intact-zona cycles; IZCs) were studied. A significantly higher number of follicles was aspirated in FZCs (7.16 +/- 3.5) than in IZCs (6.43 +/- 3.56), yielding significantly fewer immature oocytes in FZCs (1.58 +/- 1.93 vs 1.88 +/- 2.16) and a significantly higher number of atretic oocytes in FZCs (2.06 +/- 1.36 vs 0.73 +/- 1.21). No statistically significant difference was observed when the number of preovulatory oocytes obtained was compared. Nor were statistically significant differences observed as a result of either the type of stimulation [human chorionic gonadotropin (hMG), follicle-stimulating hormone (FSH), or a combination] or the aspiration technique utilized (laparoscopy vs ultrasonically guided puncture). Peripheral estradiol and progesterone and follicular fluid estradiol, progesterone, and androstenedione comparisons showed no significant differences. However, endocrine and morphologic findings (higher follicular androstenedione levels and estradiol/progesterone ratio, degenerated ooplasms) suggested some degree of late oocyte atresia, possibly due to slight hyperstimulation. In an experimental study, two healthy immature oocytes matured in vitro to the metaphase II stage showed degenerative changes in the ooplasm within 20 min after being subjected to mechanical zona pellucida (ZP) damage (mechanical fracture).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

A preclinical evaluation of pronuclear formation by microinjection of human spermatozoa into human oocytes.

In vitro fertilization (IVF) is recognized as an accepted treatment for male infertility. However, the fertilization rate is significantly lower than the fertilization rate of other IVF patient groups. Some male factor infertility patients still have a basic semen quality too poor for treatment by IVF. Microinjection of a spermatozoon directly into ooplasm has been recommended to assist fertilization in this subfertile population. This study found that oocytes from 5 of 11 patients microinjected with human spermatozoa demonstrated successful pronuclear formation and correlated with the incidence of pregnancy in these patients transferred with same-source oocytes inseminated by standard protocols. This initial evidence promotes the supposition of clinical feasibility of assisted fertilization by sperm microinjection.

Female↗
PubMed1988

The value of in vitro fertilization for the treatment of unexplained infertility.

In 54 patients referred with the diagnosis of unexplained infertility (UI), the diagnosis was confirmed in 26 (strict UI) (48%). Minimal abnormalities (MA) were found in 19 (35%); 9 (17%) had gross abnormalities and were excluded from analysis. Fifty patients with tubal infertility were randomly assigned to form a control group. Mean age and type of stimulation did not differ in the two groups. Peak follicular estradiol (E2) and terminal follicular E2 patterns were comparable. There was no difference in the mean number of oocytes retrieved per cycle. However, the control group had significantly more preovulatory oocytes: 3.6 +/- 2.0 standard deviations versus 2.8 +/- 2.1 in the overall UI group (strict UI + MA groups) and 2.7 +/- 2.2 in the strict UI group. Significantly more fertilized oocytes per cycle were obtained in the control group (P less than 0.05). The per-cycle and per-embryo transfer (ET) pregnancy rates were 32.4 and 37.3% in the overall UI group and 24 and 24.5% in the control group. The miscarriage rate was 12% in the strict UI group, 22% in the overall UI group, and 25% in the control group. It is concluded that patients with UI constitute a favorable group for in vitro fertilization and ET.

Chorionic Gonadotropin↗
PubMed1987

New method of evaluating sperm morphology with predictive value for human in vitro fertilization.

A prospective study was planned to evaluate sperm morphology as a parameter to predict the fertilization outcome in an in vitro fertilization program. Couples applying to in vitro fertilization were admitted into this project when the sperm concentration was greater than 20 million per mL and motility greater than 30 per cent. Based on new strict criteria for evaluating normal sperm morphology, patients were divided prospectively into 2 groups. In group I (25 patients) normal sperm morphology was less than 14 per cent, and in group II (71 patients) normal sperm morphology was greater than 14 per cent, using a threshold established previously. Multiple regression analysis was used to evaluate different parameters: concentration, motility, and morphology against the dependent variables, fertilization, and cleavage. The only factor which was significantly correlated with fertilization and cleavage was normal sperm morphology (P less than 0.0001). The fertilization rate (per oocyte) and the cleavage rate were 49.4 per cent and 47.6 per cent in group I and 88.3 per cent and 87 per cent in group II (P less than 0.0001). The ongoing pregnancy rate per laparoscopy and per embryo transfer was 4 per cent and 5.5 per cent, respectively, in group I and 18.3 per cent and 18.5 per cent, respectively, in group II (no significant difference). This study demonstrates the value of analyzing sperm morphology using the criteria recommended in terms of predicting fertilization and perhaps pregnancy outcome. Patients can be better counseled and the probability of fertilization or no fertilization can be more accurately established. Furthermore a trend is shown in the pregnancy rate that may indicate the importance of the male genome in establishing a pregnancy.

Embryo Transfer↗
PubMed1987

Results of in vitro fertilization attempts in women 40 years of age and older: the Norfolk experience.

Twenty-nine patients 40 years of age or older were stimulated with gonadotropins, starting on day 3 of the cycle, in a total of 64 cycles (January 1983 to June 1985) for multiple follicular development for in vitro fertilization. Most patients' infertility was due to tubal disease (n = 8) or pelvic endometriosis (n = 14). The mean number of preovulatory and immature oocytes recovered per laparoscopy was 2.53 +/- 1.73 and 1.57 +/- 1.58, respectively. There were no statistically significant differences between the number of preovulatory and immature oocytes harvested, fertilized, or transferred in this group and the number in patients younger than 40 years of age. No statistically significant differences were observed between peripheral estradiol and progesterone levels in patients 40 years of age or older and levels in patients 39 years of age or younger. There were 15 pregnancies in this group of patients, for a pregnancy rate of 23.4% per stimulated cycle, 27.7% per laparoscopy, and 29.4% per transfer. The ongoing pregnancy rate (12%) was lower, and the total abortion rate (60%) was higher, in patients 40 years of age or older in comparison with patients 39 years of age or younger. Patients 40 years of age or older should be counseled regarding the high abortion rate in this group.

Adult↗
PubMed1985

Analysis of human spermatozoa before and after processing for in vitro fertilization.

Washed incubated spermatozoa processed for in vitro fertilization were compared to the spermatozoa from the same unprocessed ejaculate in 31 randomly selected normal males (Group 1) and 7 subfertile males (Group 2). In Group 1 there was a significant increase in motility (P = 0.001) as well as a significant increase in normal morphology (P = 0.001). All categories of morphologically abnormal sperm decreased, with a significant decrease in those exhibiting small heads (P = 0.01), tapered heads (P = 0.01), cytoplasmic droplets (P = 0.001), bent midpieces (P = 0.01), or coiled tails (P = 0.02). There was also a significant decrease in immature germ cells (P = 0.001) as well as white blood cells (P = 0.02). Group 2 also showed a significant increase in motility (P = 0.01) and a significant increase in normal morphology (P = 0.01). There was a decrease in various categories of abnormal sperm, with a significant decrease in sperm with cytoplasmic droplets (P = 0.02).

Fertilization in Vitro↗
PubMed1985

Correlation of follicular fluid volume with oocyte morphology from follicles stimulated by human menopausal gonadotropin.

The maturity of human oocytes was correlated with corresponding follicular fluid volumes in 547 cycles stimulated with human menopausal gonadotropin, with or without the supplementation of follicle-stimulating hormone. Mature oocytes were found to be associated with larger follicles (average volume, 2.7 ml). Immature or degenerating oocytes were found to be associated with smaller follicles (average volume, 1.0 and 0.8 ml, respectively). Follicles without oocytes were generally quite small (average volume, 1.0 ml). We studied follicular fluid volumes associated with mature oocytes that were responsible for the establishment of pregnancy after single conceptus transfer. Analysis of these data demonstrated that the rate of spontaneous abortion was very high with conceptuses derived from smaller follicles, suggesting that oocytes from larger follicles may be of better quality.

Embryo Transfer↗
PubMed1985

Extracorporeal maturation: Norfolk, 1984.

More than one-half of the laparoscopies undertaken for oocyte retrieval in a program of in vitro fertilization yielded immature (unripened) oocytes. Seventy-three percent of these still possessed an intact germinal vesicle at aspiration. During the period from September 1981 to March 1984, in vitro maturation techniques were applied to the handling of these immature oocytes, with a resulting extracorporeal maturational success reaching 82-85%. The monitoring of germinal vesicle breakdown was essential to determining the fate of the oocytes. No oocytes were successfully fertilized that had normal dipronuclear development unless first polar body extrusion was observed prior to insemination. However, once matured in vitro, these oocytes were fertilized at rates nearly equal to that of mature or preovulatory oocytes. When interval periods of 29 hours between follicular aspiration and oocyte insemination were constant, the incidence of polyspermic fertilization was higher in oocytes that did not possess a germinal vesicle at aspiration compared to that in oocytes with a germinal vesicle. The method of follicular stimulation for ovulation induction was examined to determine whether differences in developmental potential existed between cycles stimulated with hMG alone, FSH alone, or a combination of FSH/hMG. Although fertilization rates were somewhat lower in the combination group, this may have been due to the small number of oocytes involved in that sample. A 50% increase in the number of immature oocytes harvested from FSH cycles was noted. The increasingly higher number of immature oocytes collected for in vitro fertilization underscores the importance of developing reliable in vitro maturation techniques.

Chorionic Gonadotropin↗
PubMed1984

Three years of in vitro fertilization at Norfolk.

During the 3 years from 1981 to 1983, 319 consecutive patients in 560 cycles were treated in a program of in vitro fertilization at Norfolk. All patients were stimulated by human menopausal gonadotropin supplemented by human chorionic gonadotropin. There were transfers in 429 cycles, resulting in 105 pregnancies. Over the 3-year span, the pregnancy rate by cycle was 19%; by transfer, 25%; and by patient, 33%.

Adult↗
PubMed1983

Maturation and fertilization of morphologically immature human oocytes in a program of in vitro fertilization.

Oocytes of varying stages of maturity were aspirated from follicles primed with either human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG) or a combination of follicle-stimulating hormone (FSH), hMG and hCG. Of the aspirated oocytes from 44 cycles, 74 were considered to be immature by virtue of morphologic characteristics of the oocytes and the degree of intercellular expansion of the associated cumular and membrana granulosa cells. After incubation periods of 22 to 35 hours in a Ham's F-10-based culture medium, these immature oocytes were inseminated with sperm donated by the patient's husband. Ultimately, 44 conceptuses were transferred to the respective uteri of 30 patients. Eight pregnancies were established as a result of these 30 transfers, two of which resulted from the transfer of only developed immature oocytes.

Chorionic Gonadotropin↗
PubMed1983

Vital initiation of pregnancy (VIP) using human menopausal gonadotropin and human chorionic gonadotropin ovulation induction: Phase I--1981.

Laparoscopies for oocyte aspiration in 31 cycles were performed on 25 patients receiving human menopausal gonadotropin and human chorionic gonadotropin. Sixty oocytes were aspirated, of which 48 were considered preovulatory. Ninety-seven percent (58 of 60) of the oocytes were found in the original aspirate, and the remaining oocytes were found in either the first or second follicle wash. The fertilization rate per preovulatory oocyte was 33% (16 of 48), whereas on a per cycle basis it was 39% (12 of 31). A total of 15 conceptuses (2-cell = 5; 3-cell = 3; 4-cell = 7) were transferred to 12 patients, and two pregnancies were established. These pregnancies were established by transfers of 3-cell and 4-cell conceptuses at approximately 47 hours after insemination. Both pregnancies resulted in term deliveries of normal infants.

Cell Separation↗
PubMed1983

Vital initiation of pregnancy (VIP) using human menopausal gonadotropin and human chorionic gonadotropin ovulation induction: phase II--1981.

In a program for in vitro fertilization, laparoscopies for oocyte aspiration were performed on 24 patients receiving human menopausal gonadotropin and human chorionic gonadotropin. Of the 40 preovulatory oocytes that were recovered from these patients, 33 (83%) were fertilized and 30 (75%) cleaved and were transferred. Ten immature oocytes were collected, and attempts were made to mature these in vitro prior to insemination. All ten oocytes (100%) did fertilize, and seven (70%) cleaved and were transferred. Morphologic variation was noted between cleaving conceptuses, even in those conceptuses responsible for establishing pregnancies. Five pregnancies resulted from 19 embryo transfers (26%).

Chorionic Gonadotropin↗