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Biomedical subjects

T F Kruger

Publications and source records attributed to T F Kruger.

At least 55 records · Page 3Linked to original sources

Follicle stimulating hormone levels on cycle day 3 predict ovulation stimulation response.

AIM: To determine the value of basal follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) levels on cycle day 3 in predicting the ovulation stimulation response in patients receiving exogenous gonadotropins for in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT). METHODS: One hundred eleven consecutive females with infertility due to various etiologies were investigated. Cycle day 3 serum levels of FSH, LH, and E2 were determined prior to ovulation induction with a combination of clomiphene citrate and human gonadotropins. Follicular growth was monitored ultrasonically, and when appropriate, oocytes were recruited, counted, graded, and then used, as prearranged, for either IVF or GIFT. Basal hormone levels were compared to the peak E2 concentration, the number of follicles aspirated, and the number of preovulatory oocytes recovered following drug therapy. Details of resulting pregnancies were also recorded. RESULTS: Patients with low basal FSH levels (< 11.5 mIu/ml) yielded a higher mean number of preovulatory oocytes than those with high values (> 11.5 mIu/ml), i.e., 6.7 oocytes per cycle vs 2.5 oocytes (P < 0.001). In the low group 97% of cycles yielded more than three fertilizable oocytes compared to 42% in the high group (P < 0.5). There were 16 term pregnancies (16%) in the low group and 1 (8.3%) in the high group. Basal LH and E2 levels did not improve on the ability to distinguish between different populations of infertile females who responded differently to ovulation induction. CONCLUSION: Cycle day 3 FSH levels are predictive of the ovulation response and probability of pregnancy in stimulated cycles and can be of value in patient selection and counseling in IVF and GIFT programs.

Abortion, Spontaneous↗

Comparative trial of clomiphene citrate/human menopausal gonadotropin and the contraceptive pill, followed by clomiphene citrate/human menopausal gonadotropin, in a gamete intrafallopian transfer program.

PURPOSE: It may sometimes be necessary to regulate cycles in assisted reproduction. Cycles can be regulated with gonadotropin releasing hormone (GnRHa) agonist but other methods can also be used. The aim of this study was to compare the pregnancy rate in a gamete intrafallopian transfer (GIFT) program in patients receiving a contraceptive pill/Clomid/human menopausal gonadotropin (hMG) regimen (study group), with the standard Clomid/hMG regime (control group). Fifty one patients in the study group were carefully matched for patient age, infertility diagnosis (female), semen parameters, number of follicles, and number of oocytes transferred into consideration with a control group. RESULTS: The overall pregnancy rate was 21.6% (11/51) in the study group and 47% (24/51) in the control group (P = 0.01). However, the ongoing pregnancy rate in the two groups did not differ significantly, 11.8% (6/51) vs 27.5% (14/51) (P = 0.08). In the study group, 7.8% of patients had to be seen over a weekend, compared to 13.7% in the control group (not significant). CONCLUSION: From the findings we conclude that, although this method of controlling cycles can be useful in selected patients, it is not the ultimate method.

Adult↗

A new computerized method of reading sperm morphology (strict criteria) is as efficient as technician reading.

OBJECTIVES: To compare the ability of a computerized method of sperm morphology with the manually recorded method in predicting in vitro fertilization (IVF) results, to compare results obtained by both methods, and to determine the intraobservation variability. DESIGN, SETTING, PATIENTS: Forty-three stained semen slide preparations from two large level-three academic institutions' reproductive endocrinology units (IVF programs) were blindly evaluated, and the sperm were classified into normal and amorphous forms. RESULTS: Experiment 1: Twenty-one slide preparations from the Tygerberg gamete intrafallopian transfer program were manually evaluated; the fertilization rates for the groups with < 14% and > 14% normal sperm forms were 33.3% (15/45 oocytes) and 76.6% (46/60 oocytes), respectively. Corresponding fertilization rates with FERTECH were 46.8% (30/64) and 75.6% (31/41). Experiment 2: Twenty-two slide preparations from the Norfolk IVF program were evaluated. The manual method reported a fertilization rate in the group with < 14% normal forms of 27.4% (14/51 oocytes) compared with 90.0% (127/141 oocytes) in the group with > 14% normal forms. Corresponding figures for the FERTECH method were 33.9% (18/53) and 88.4% (123/139), respectively. Experiment 3: When the 43 slide preparations were blindly evaluated using both methods, 84% of the FERTECH evaluations correlated well with the manual method and FERTECH ability to diagnose the subfertile male (< 14% normal forms) was 95% (sensitivity). Experiment 4: A total of 16 different slides (8 per group) were randomly selected and analyzed five times (100 cells per reading) by the computerized method. The slides were obtained from men with normal sperm morphology of < 14% and > 14% as classified by the manual method. In the first group (< 14%) 97.5% (39/40) of the readings classified the sperm in the proper category, whereas in the second group (> 14%) 95% (38/40) of the cases were correctly identified. CONCLUSION: Using strict criteria for morphology evaluation, there is a positive and significant correlation between FERTECH evaluation and manual assessment. The reproducibility of the computerized method and the ability to distinguish between fertile and subfertile groups using those criteria are good.

Evaluation Studies as Topic↗

The hemizona assay: its role in identifying male factor infertility in assisted reproduction.

OBJECTIVES: To identify male factor infertility among a group of patients in an assisted reproductive program (phase 1) and to evaluate the hemizona assay (HZA) in the diagnosis and prognosis of such a program (phase 2). DESIGN: The IVF performance of normal gametes in the Tygerberg program were critically evaluated. Female patients were classified as pure tubal factor infertility, having a normal FSH:LH ratio on day 3 of the menstrual cycle. All participating women produced three or more preovulatory oocytes at retrieval and were inseminated with sperm considered normal by all present diagnostic criteria. The total and normal fertilization rate thresholds were defined in that group. Using those thresholds, couples tested for sperm binding in the HZA (n = 48) were used and divided into two groups according to their fertilization rates, namely group 1, low fertilization (< 55%) and group 2, normal fertilization (> 55%). SETTING: University-based tertiary care center. PATIENTS: Ninety-nine couples (589 oocytes) with pure tubal factor infertility and normal male factor were used in phase 1. Forty-eight couples with normal and abnormal male factors that had both HZA performed and IVF treatment were included in phase 2. RESULTS: Investigation of the performance of normal gametes in 99 couples (589 oocytes) revealed the total fertilization rate (total number of oocytes fertilized/total number of oocytes inseminated) was (mean +/- SD) 88.6% +/- 16.8% and the normal fertilization rate (total number of oocytes with normal fertilization/total number of oocytes inseminated) was 81.3% +/- 22%. The minimum total fertilization rate that can be considered normal in the Tygerberg program using mean--2 SD is therefore 55% and for normal fertilization rate is 37%. The group with low fertilization rate (< 55%) showed a mean hemizona index (HZI) significantly lower; nevertheless, the distribution overlapping indicates a low discriminating power of the HZA. A sensitivity of 75% and a specificity of 75% were found; the positive and negative predictive values were 81% and 68%, respectively. CONCLUSIONS: The results indicated the HZA and HZI contribute important information and can serve in conjunction with other semen characteristics as useful tools during the diagnosis of the male factor in assisted reproduction.

Chorionic Gonadotropin↗

The ability of the hemizona assay to predict human fertilization in different and consecutive in-vitro fertilization cycles.

The objective of this prospective study was to examine the ability of the hemizona assay (HZA) to predict fertilization outcome of mature, pre-ovulatory oocytes under in-vitro fertilization (IVF) conditions. Since a large number of patients were evaluated over a long period, the power of the HZA to prognosticate fertilization results in the same and subsequent (consecutive) IVF cycles of those same patients was assessed. For IVF, only metaphase II oocytes were used. For the HZA, both fresh oocytes donated by patients at the time of IVF and oocytes recovered from surgically removed ovarian tissue (and salt-stored) were used, and bisected by micromanipulation techniques. Matching hemizonae were co-incubated either with spermatozoa from the patient (test) or from a fertile man (control) for 4 h. The number of spermatozoa tightly bound to the zona was counted. Patients (n = 112) were divided into two groups based on HZA results (expressed as HZA index or HZI): HZI > or = 30% (n = 72) and < 30% (n = 40). The patients with HZI < 30% had significantly lower fertilization rates in both the HZA-IVF cycle and in subsequent cycles compared to patients with HZI > or = 30% (P < 0.03). Linear discriminant analysis indicated the HZA to have a sensitivity of 84%, and positive and negative predictive values of 85 and 70% respectively, for prediction of fertilization outcome in a total of 233 cycles. It was concluded that the HZA is a good predictor of fertilization rate in vitro, and can be used in the IVF setting to supply additional clinical information in male-factor patients.

Female↗

Genital tuberculosis at Tygerberg Hospital--prevalence, clinical presentation and diagnosis.

Over a period of 30 months (1 July 1986-31 December 1988) 57 cases of genital tuberculosis were diagnosed at Tygerberg Hospital. Forty of these cases were diagnosed as a result of routine screening in 650 patients who presented with infertility and the other 17 were diagnosed in patients admitted to the gynaecological wards. The prevalence in patients presenting with infertility was 6.15%. The commonest gynaecological presenting symptom was infertility (73.7%). Dysmenorrhoea in 29.8% and deep dyspareunia in 12.3% were the only other frequently occurring gynaecological symptoms. Menstruation was normal in 50 patients (87.7%). Seven per cent of patients were postmenopausal. Abdominal symptoms were only present in 15.8%. These findings re-emphasise that genital tuberculosis is often a disease of absent or few symptoms. General, abdominal and pelvic examinations were normal in 56.1% of patients and even when clinical signs were present they were nonspecific. Menstrual fluid collection and culture proved to be the most reliable diagnostic procedure, since it was positive in 11 patients in whom premenstrual endometrial sample cultures were negative and also in 17 patients in whom histological examination of premenstrual endometrial samples for tuberculosis were negative. The possible reasons for this and its clinical importance are discussed. Other than histological examination of operation and/or biopsy specimens, special investigations proved to be of little help in the diagnosis of genital tuberculosis.

Adult↗

The role of oocyte maturity in the treatment of infertility because of teratozoospermia and normozoospermia with gamete intrafallopian transfer.

OBJECTIVE: To determine the effect of oocyte maturity on pregnancy rate (PR) in patients undergoing gamete intrafallopian transfer (GIFT) procedures for infertility and in whom male partners had either normozoospermia or teratozoospermia. DESIGN: A prospective study using a combination of clomiphene citrate and human menopausal gonadotropin for ovulation induction was carried out. Five hundred thirty-seven GIFT treatment cycles were analyzed, and 423 cycles yielded four or more oocytes. Patients were divided into two groups according to the sperm morphology: those with less than 14% normal forms and those with greater than 14% normal morphology (as judged by strict criteria). These two groups were divided into a further five subcategories depending on the number of metaphase II oocytes transferred. RESULTS: In the group less than 14% normal forms (category I; 4 metaphase I oocytes replaced), three pregnancies resulted from 33 cycles (9.09%), and in category V (4 metaphase II oocytes transferred) the PR was 15% (14/95) per cycle. In the group with greater than 14% normal forms, in category I, the PR was 16% (3/19) per cycle, and in category V, the PR was 33% (20/61) per cycle. The effect of morphology (less than 14% normal forms versus greater than 14% normal forms) on pregnancy outcome is significant (P = 0.0161). The overall effect of increasing the number of metaphase II oocytes on the pregnancy outcome was not significant (P = 0.1098). However, in the group with greater than 14% normal forms, there was a significant improvement in PR (P = 0.04) in category V. CONCLUSION: During this prospective study, it was shown that sperm morphology plays a significant role in the pregnancy outcome in a GIFT program.

Female↗

The Acridine Orange test: determining the relationship between sperm morphology and fertilization in vitro.

The prediction of human fertilization is an important aspect of research protocols dealing with male fertility. Sperm DNA has been reported to be an indicator of human sperm fertility potential. The Acridine Orange test for evaluation of sperm DNA has been employed during the present study to determine its relationship with human sperm morphology and fertilization in vitro. Seventy-six patients from the in-vitro fertilization (IVF) and/or gamete intra-Fallopian transfer (GIFT) programme were randomly selected for the study. All patients had a routine semen analysis, sperm DNA evaluation and underwent standard IVF procedures at the time of the study. The results indicated a moderate positive correlation (r = 0.38, P = 0.0006) between results of the Acridine Orange test and normal sperm morphology. Patients with an Acridine Orange test value exceeding 24% had significantly higher oocyte fertilization rates than patients with lower values, for metaphase I (74 versus 51%, P = 0.0008) and for metaphase II oocytes (88 versus 60%, P = 0.0001). Sperm morphology, however, proved to be a more significant predictor of fertilization in vitro compared to the Acridine Orange test.

Acridine Orange↗

The influence of solubilized porcine zona pellucida protein on the binding capacity of human spermatozoa.

The acrosome reaction, sperm-zona pellucida binding, sperm-oolemma binding/fusion and subsequent fertilization are known to be influenced by homologous as well as heterologous follicular fluid and zona pellucida protein. In this study, the effect was investigated of different concentrations of solubilized porcine zona pellucida protein on the zona binding potential of human spermatozoa under hemizona assay conditions. Human spermatozoa incubated with 617 and 142 micrograms/ml porcine zona pellucida protein showed a statistically significant increase in zona binding when compared with control spermatozoa (106.5 +/- 18.0 versus 60.9 +/- 29.0, P less than 0.02 and 111.0 +/- 26.6 versus 63.0 +/- 25.5, P less than 0.0001, respectively). Concentrations of 67 micrograms/ml porcine zona pellucida protein did not show a significant increase in zona binding (78.7 +/- 21.7 versus 66.7 +/- 25.4, P greater than 0.05). Control zona binding values for different experiments did not differ significantly (60.9 +/- 29.0; 63.0 +/- 25.5; and 66.7 +/- 25.4, P greater than 0.6). In conclusion, it seems likely that a factor(s) present in the porcine zona pellucida might play a beneficial role during human sperm-oocyte binding. The results of the study might be used in future investigations to manipulate gamete interaction to such an extent that improved fertilization rates can be accomplished.

Animals↗

Comparison of sperm binding potential of uninseminated, inseminated-unfertilized, and fertilized-noncleaved human oocytes under hemizona assay conditions.

In this study, human oocytes obtained after ovarian hyperstimulation for in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) were utilized to evaluate sperm/zona pellucida binding potential. Three groups of oocytes were evaluated: 1) uninseminated; 2) inseminated-unfertilized; and 3) fertilized-uncleaved. All oocytes had undergone germinal vesicle breakdown at the time of retrieval and were salt-stored (pH 7.2) for not more than 30 days. Sperm binding was recorded under hemizona assay (HZA) conditions using spermatozoa from eight fertile men (HZA control) and from 1) four teratozoospermic (HZA test) and 2) four normozoospermic (HZA test) infertile men. First, the mean numbers (+/- SD) of sperm tightly bound for fertile controls and teratospermic men to hemizonae from uninseminated oocytes were 69.7 +/- 16 and 14.5 +/- 7, respectively (P = 0.02). Likewise, hemizonae from uninseminated oocytes bound 102.0 +/- 19 and 114.0 +/- 28, respectively, for fertile controls and normospermic men (P = 0.5). Second, hemizonae obtained from inseminated-unfertilized IVF oocytes bound 44.2 +/- 12 and 19.7 +/- 6 for fertile controls and teratospermic men, respectively (P = 0.02). This category of oocytes bound 100.5 +/- 7 and 108.5 +/- 11 sperm, respectively, for fertile controls and normospermic semen (P = 0.3). Third, HZA results of fertilized but uncleaved oocytes showed a mean number of tightly bound sperm of 6.0 +/- 4 compared with 65.0 +/- 1 in control, uninseminated oocytes using fertile sperm. These results demonstrate that uninseminated and inseminated-unfertilized human oocytes, salt-stored under controlled pH conditions, give reliable information regarding sperm binding potential under HZA conditions.

Female↗

Sperm selection capacity of the human zona pellucida.

Previous hemizona assay (HZA) results have illustrated a positive and significant correlation between the percentage of morphologically normal spermatozoa in the semen and the number of spermatozoa tightly bound to the zona pellucida. The present study was designed to evaluate the morphologic features using strict criteria of spermatozoa tightly bound to the zona pellucida. Semen samples of 4 normozoospermic and 11 teratozoospermic men were used to compare the percentage of normal spermatozoa in the semen with that found 1) after swim-up separation and 2) bound to the zona under HZA conditions. The mean (+/- SEM) % normal forms for normozoospermic men in semen, after swim-up and zona-bound spermatozoa were 21.5 +/- 1.6, 27.5 +/- 2.9, and 44.8 +/- 3.4, respectively. A significantly higher % of normal forms were found among zona-bound sperm compared to swim-up forms (p = 0.02) and seminal sperm (p = 0.02). The mean % of normal sperm forms present in semen, after swim-up and zona pellucida-binding for teratozoospermic men, were 3.7 +/- 0.9, 5.8 +/- 1.6 and 15.6 +/- 3.1, respectively. Significant differences existed between the % of normal sperm forms found in the swim-up and zona-bound spermatozoa (P = less than 0.01 and P = less than 0.0003, respectively) compared to the original ejaculates. Results indicate that a selective process against abnormal spermatozoa occurs at the site of the zona pellucida.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Separation↗

Hemizona assay: use of fresh versus salt-stored human oocytes to evaluate sperm binding potential to the zona pellucida.

The hemizona assay (HZA) has a high predictive value for in vitro fertilization (IVF) results. Oocyte quality plays a significant role in the validation of this test. The question was asked whether human salt-stored oocytes (up to 30 days) are damaged and subsequently lose their sperm binding capacity when compared to fresh human oocytes. Equivalent binding in both the salt-stored and the fresh group of oocytes was observed in the hemizonae incubated with normal semen as well as in their matching halves incubated with semen from an infertile man. Based on the results, we conclude that salt-stored oocytes (pH 7.0) give reliable information regarding sperm binding potential under HZA conditions.

Female↗

Recurrent failure of in vitro fertilization: role of the hemizona assay in the sequential diagnosis of specific sperm-oocyte defects.

The results of predictive fertilization bioassays (hemizona assay, hamster ova-human sperm penetration assay), in vitro fertilization treatment, fertile donor cross-match tests with either sperm or oocytes, and oocyte micromanipulation for assisted fertilization were used to establish a pathophysiologic diagnosis in cases of recurrent failed fertilization in vitro. Disorders of sperm function manifested at the level of zona binding, zona penetration, oolemma fusion, and pronuclear decondensation as well as oocyte anomalies were considered to represent the specific gamete defects that led to abnormal sperm-oocyte interactions (i.e., failed fertilization). Our findings show that the sequential application of bioassays can elucidate specific sperm or oocyte defects that characterize functional abnormalities among sperm populations.

Acrosome↗

Human preovulatory oocytes have a higher sperm-binding ability than immature oocytes under hemizona assay conditions: evidence supporting the concept of "zona maturation".

OBJECTIVE: The purpose of this study was to investigate the sperm-binding potential of human oocytes at different stages of nuclear maturation under hemizona assay (HZA) conditions. DESIGN: This was a prospective study designed in a blinded fashion. SETTING: Academic research environment approved by the Institutional Review Board. PATIENTS: Surplus oocytes, donated by patients undergoing in vitro fertilization therapy after gonadotropin stimulation, were analyzed. Semen from a fertile donor was used in all assays. INTERVENTIONS: Five groups of oocytes were considered: (1) immature, prophase I; (2) metaphase I; (3) metaphase II; (4) inseminated, unfertilized metaphase II; and (5) immature, prophase I oocytes matured in vitro to metaphase II. Oocytes were stored in salt solution (pH 7.2) and microbisected before assay. MAIN OUTCOME MEASURE(S): Tight binding of sperm to the zona pellucida under HZA conditions was evaluated after 4 hours of gametes coincubation. RESULTS: Metaphase II oocytes (groups 3 and 4) had significantly higher binding than other groups (P = 0.0001). The mean value of the difference between the two halves (hemizona) was not significant, thus showing a small intra-assay variation for all maturational stages. CONCLUSIONS: Full meiotic competence of human oocytes is associated with an increased zona pellucida-binding potential.

Double-Blind Method↗

Detection of sperm antibodies on unwashed spermatozoa with the immunobead test: a comparison of results with the routine method and seminal plasma TAT titers and SCMC test.

This study investigated whether the immunobead test (IBT) could, for the purposes of simplicity and saving time, be applied directly on an unwashed semen sample instead of washed spermatozoa. These two methods were performed simultaneously on the semen samples of 15 men with a positive MAR test and 10 men with a negative MAR test. A possible association was found between the unwashed samples, showing positive IB binding (greater than 20%) on the tail and/or head and the seminal plasma TAT titers (P less than .00001, Fisher's exact test). In all cases with IB binding of greater than or equal to 20% on unwashed spermatozoa, positive seminal plasma TAT titers (greater than or equal to 32) and SCMC tests (greater than or equal to 50%) were found. In all cases where the binding of the beads was mainly located on the tailtips of the washed or unwashed spermatozoa, negative seminal plasma TAT titers and SCMC tests were found. Coating of the head and/or upper tail regions in both methods was always associated with high TAT titers and a strong-positive SCMC test. It is concluded that the IBT for IgA, but not for IgG, can be performed directly on unwashed semen and that the position of IB binding on the spermatozoa is of prognostic importance with regard to the expected outcome of the SCMC test and seminal plasma TAT titers.

Agglutination Tests↗