Value of sperm characteristics and the result of in-vitro fertilization for predicting the outcome of assisted reproduction

Are sperm DNA fragmentation, hyperactivation, and hyaluronan-binding ability predictive for fertilization and embryo development in in vitro fertilization and intracytoplasmic sperm injection?

OBJECTIVE

To determine the diagnostic value of the following sperm function tests in predicting the fertilizing ability of spermatozoa in conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI): hyaluronan-binding assay (HBA), DNA fragmentation (Halosperm), and hyperactivity.

DESIGN

Prospective study.

SETTING

University medical center.

PATIENT(S)

133 couples undergoing infertility treatment with IVF/ICSI.

INTERVENTION(S)

Analysis of sperm DNA fragmentation, hyaluronan-binding ability, and hyperactivation on washed semen samples used for the insemination of oocytes.

MAIN OUTCOME MEASURE(S)

Correlation between the results of sperm function tests and the fertilization rate (FR) or embryo quality (EQ) after IVF and ICSI. Comparison of the sperm DNA fragmentation, hyperactivation, and hyaluronan binding ability between cycles with less than 50% (group 1) and more than 50% (group 2) of oocytes fertilized after IVF.

RESULT(S)

Both FR and EQ in IVF cycles negatively correlated with sperm DNA fragmentation. Furthermore, a positive correlation was observed between FR and hyaluronan-binding ability or induced hyperactivity. The semen samples from the IVF cycles with low FR (group 1) were characterized by statistically significantly higher sperm DNA fragmentation and lower hyaluronan-binding ability in comparison with semen samples from the group with high levels of fertilization (group 2). In ICSI cycles, no relationship was found between sperm function tests and FR or EQ.

CONCLUSION(S)

The Halosperm test, the HBA test, and induced hyperactivity are useful in predicting the ability of spermatozoa to fertilize oocytes in IVF and are helpful in distinguishing semen samples suitable for IVF or ICSI.

Prognostic value of evaluation of total number of morphological anomalies in 100 sperm in semen of infertile men

In this study, the evaluation of the total number of morphological anomalies per 100 sperm was more reliable, as far as potential fertility is concerned than the concentration of sperm per milliliter, the percentage of motile sperm, and the percentage of sperm with normal or abnormal morphology. This parameter allows for discrimination between subfertile and fertile semen and therefore can help in the selection of men who require assisted reproduction techniques.

New semen quality scores developed by principal component analysis of semen characteristics

The purpose of this study was to determine whether semen characteristics can be reduced to 2 semen quality (SQ) scores and whether these new scores can help the clinician in assessing the reproductive outcome. A cross-sectional sample of 250 patients seeking infertility treatment were analyzed for semen characteristics. In addition, 177 male-factor patients (prostatitis with infection, n = 40; varicocele, n = 77; varicocele with infections, n = 11; and vasectomy reversal, n = 43) were also assessed. Sperm motion kinetics were measured by computer-assisted semen analysis (CASA) (concentration, percent motility, curvilinear velocity [VCL], straight-line velocity [VSL], average path velocity [VAP], linearity [LIN], and amplitude of lateral head displacement [ALH]). Sperm morphology was assessed by both World Health Organization (WHO) guidelines and Tygerberg strict criteria. The principal component analysis model was used to construct an SQ score and a relative semen quality (RQ) score. A separate set of 25 normal donors was included as controls to determine normal ranges of the semen scores. Among the patient samples, SQ and RQ scores (median and 25% and 75% interquartile values) were 89.9, 25.1, and 130.4 and 106.1, 45.2, and 165.9, respectively. The SQ score for the varicocele and varicocele with infection groups was comparable (78.6 +/- 17.4 and 84.8 +/- 20.6) but significantly different from the control (100 +/- 10, P <.001 and.03). Vasectomy reversal patients had an SQ score of 78.2 plus or minus 16.8 that was significantly lower than controls (P <.001). The correlation among semen characteristics allows for the efficient combining of semen measures. The composite scores can summarize overall SQ and quantity. Both SQ and RQ scores provide meaningful information on the quality of semen specimens for the clinician.

Progesterone Receptor as an Indicator of Sperm Function

Expression of progesterone receptor (PR) localization on spermatozoa was determined in men with normal and abnormal spermiograms. Studies were also carried out to evaluate the potential of PR as a marker of sperm function. Progesterone receptor expression on spermatozoa from men with normozoospermia (n = 8), oligozoospermia (n = 7), asthenozoospermia (n = 8), oligoasthenozoospermia (n = 7), and teratozoospermia (n = 11) was analyzed using an immunocytochemical method with monoclonal antibodies against PR, and flow cytometry using a cell-impermeable fluorescein-tagged progesterone coupled to BSA complex (P-FITC-BSA). Both methods revealed significantly fewer (P < 0.05) PR-positive spermatozoa in men with oligozoospermia, asthenozoospermia, oligoasthenozoospermia, and teratozoospermia compared with men with normozoospermia, thereby suggesting that down-regulation of PR expression in spermatozoa may be one of the causes of male infertility. Spermatozoa from men with normozoospermia (n = 12), oligozoospermia (n = 12), asthenozoospermia (n = 12), oligoasthenozoospermia (n = 9), and teratozoospermia (n = 10) were exposed to low osmotic conditions in the hypoosmotic swelling (HOS) test and then analyzed for PR expression using P-FITC-BSA complex. A significantly higher percentage (P < 0.05) of spermatozoa with physiologically active plasma membrane (HOS+) lacked PR expression (HOS+PR-) in all categories of men with infertility, thereby suggesting that compared to the HOS test, PR expression is a better indicator of sperm function. Furthermore, PR expression in spermatozoa showed a strong (P < 0.05) positive correlation with their ability to undergo an in vitro acrosome reaction. This was observed in all study groups (i.e., normozoospermia, r = 0.8545; oligozoospermia, r = 0.8711; asthenozoospermia, r = 0.7645; oligoasthenozoospermia, r = 0.9003; and teratozoospermia, r = 0.8676). This suggests a potential role for PR in the events leading to the acrosome reaction in sperm.

Use of the total motile sperm count to predict total fertilization failure in in vitro fertilization

OBJECTIVE

To evaluate the capacity of baseline characteristics and total motile sperm count (TMC) to predict total fertilization failure (TFF) in patients undergoing IVF.

DESIGN

Retrospective cohort study.

SETTING

University hospital.

PATIENT(S)

Eight hundred ninety-two couples with a total of 1,569 consecutive IVF cycles.

INTERVENTION(S)

Prewash and postwash TMC during fertility workup and at the time of ovum pickup (OPU).

MAIN OUTCOME MEASURE(S)

Analysis of logistic regression and the receiver operating characteristic curve were used to determine which variables could be used to predict TFF.

RESULT(S)

The area under the curve (AUC) for prewash TMC during fertility workup was 0.72, similar to a combination of pre- and postwash TMC. At the time of OPU, both pre- and postwash TMC had an AUC of 0.73. A model based on selected baseline characteristics (male age, number of IVF cycles, indication for IVF, and prewash TMC during fertility workup) had an AUC of 0.75. A model at the time of OPU, including the number of oocytes, had an AUC of 0.80.

CONCLUSION(S)

The use of both models, one before start of the IVF cycle and one at the time of OPU, allows an accurate prediction of the chance of TFF and is useful in counseling patients on whether to opt for IVF or ICSI.

Intra- and inter-laboratory variability in the assessment of sperm morphology by strict criteria: impact of semen preparation, staining techniques and manual versus computerized analysis

We designed prospective studies to compare manual and computerized analysis of sperm morphology by strict criteria using different semen processing and staining techniques. A total of 54 semen samples were studied; slides were prepared from each subject from liquefied semen and after washing, and stained with Diff-Quik or Papanicolaou. An intra-laboratory, blind assessment was performed manually (two observers) and using a computerized analyser (two readings). This demonstrated a very good correlation between manual analysis of liquefied and washed samples with both staining techniques [intraclass coefficient (ICC) = 0.93 and 0.83]. Greater agreement was observed between computerized readings (washed samples) of Diff-Quik (ICC = 0.93) than of Papanicolaou-stained slides (ICC = 0.66). An excellent intra-laboratory correlation was observed for within-computer readings (ICC = 0.93). There was moderate agreement between inter-laboratory computer readings (two centres, ICC = 0.72). Although there was lower inter-laboratory agreement for manual and manual versus computer readings, overall results of all manual and computer analyses showed good agreement (ICC = 0.73). Diff-Quik staining is reliable for both manual (liquefied) and computer (washed) analysis of strict sperm morphology. Intra- and inter-computer analyses using this method reached satisfactory levels of agreement. There is still high inter-laboratory variability for the manual method.

Preparation by differential gradient centrifugation is better than swim-up in selecting sperm with normal morphology (strict criteria)

OBJECTIVE

To evaluate two commonly used methods of sperm preparation with respect to their effects on sperm morphology (strict criteria).

DESIGN

Auto-controlled, split sample study performed on the semen of 74 male partners of couples enrolled for IVF.

SETTING

In vitro fertilization and andrology laboratories at a tertiary care, major teaching hospital.

PATIENT(S)

Seventy-four male partners of couples who were scheduled to undergo IVF.

INTERVENTION(S)

Equal halves of the same semen sample were evaluated for strict criteria sperm morphology before and after preparation by differential gradient centrifugation using Percoll (Pacific Andrology, Montrose, CA) and by the standard swim-up method.

MAIN OUTCOME MEASURE(S)

The percentage of morphologically normal sperm was assessed using strict criteria before and after the two methods of sperm preparation. Specific parameters studied were individual abnormalities of the head, midpiece, and tail.

RESULT(S)

Sperm preparation using differential gradient centrifugation with Percoll produced a significantly greater number of specimens with normal sperm morphology and also showed higher absolute quantitative improvement over the swim-up method. The two methods were comparable in regard to their effects on specific sperm abnormalities (i.e., head, midpiece, and tail defects).

CONCLUSION(S)

The differential gradient sperm separation method using Percoll is superior to the swim-up method for selecting sperm with normal morphology as assessed by strict criteria. Because sperm morphology as assessed by strict criteria is a good predictor of oocyte fertilization, this method can be recommended as the method of choice for assisted reproductive technology laboratories. Use of this method may help improve outcome by increasing fertilization rates.

The sperm deformity index: a reliable predictor of the outcome of oocyte fertilization in vitro

OBJECTIVE

To evaluate a novel expression of sperm morphological parameters, the sperm deformity index, as a predictor of fertilization in vitro.

DESIGN

Prospective blind clinical trial.

SETTING

Academic tertiary referral center.

INTERVENTION(S)

Detailed sperm morphological assessment applying strict morphological criteria and a multiple entry technique for an unselected male population undergoing IVF. The sperm deformity index, defined as the average number of deformities per sperm assessed, was calculated.

PATIENT(S)

One hundred fifty-eight patients undergoing IVF treatment. Females with conditions negatively influencing fertilization were excluded.

MAIN OUTCOME MEASURE(S)

Fertilization rates and pregnancy.

RESULT(S)

Seventy-three percent of patients achieved fertilization. Patients achieving fertilization had a significantly higher median proportion of normal forms and a significantly lower median sperm deformity index than the nonfertilizers. The receiver operator characteristic (ROC) curves identified cutoff points that maximized the sum of sensitivity and specificity at sperm deformity index 1.6 and normal forms 4%. The sperm deformity index had a greater sensitivity (96%), specificity (72%), positive predictive value (90%), and negative predictive value (86%) than the proportion of normal sperm morphology (87%, 69%, 89%, 66%, respectively) at the optimal cutoff points. The area under the ROC curve was greater for the sperm deformity index (0.875) than for the proportion of normal sperm morphology (0.622). Achieving pregnancy did not correlated with sperm morphology.

CONCLUSION(S)

The sperm deformity index is a more reliable predictor of the outcome of fertilization in vitro than the proportion of normal sperm morphology and can assist to identify patients who require techniques such as intracytoplasmic sperm injection.

Evaluation of the immunological cause of male infertility

The presence of antisperm antibodies was considered as one of the main causes of male infertility. This study was conducted on 776 semen samples of the male partners of infertile couples in order to evaluate the immunological factor. The detection of antisperm antibodies was performed by means of the direct Mixed Antiglobulin Reaction (MAR) test. A positive test was found in 35 samples. Hence, the prevalence of immunological infertility in this study is 4.5% among the male partners of infertile couples. Further explorations were performed on men with positive results, in order to detect the presence of antibodies in the sera by means of the indirect MAR tests, and sperm immobilization tests for quantitating the cytotoxic activity of the antibodies. The indirect MAR tests showed that 97% of the antibodies were present in sera, whereas 51% of the samples were cytotoxic. Routine semen analysis indicated that around 60% of the semen samples with antisperm antibodies were good. Semen culture showed that positive results were detected in 40% of samples. Clinical evaluations revealed that the presence of antisperm antibodies may have been the cause of long-standing infertility, on average 5 years, and were not all primary. Evaluations of all clinical and laboratory findings indicated that unilateral testis obstruction and male accessory gland infection were the main pathologies found.

The combination of two semen preparation techniques (glass wool filtration and swim-up) and their effect on the morphology of recovered spermatozoa and outcome of IVF-ET

The aim of this prospective study was to relate sperm quality, especially sperm morphology, to the outcome of IVF results, when glass wool filtration (GWF) and swim-up were used in combination for the preparation of spermatozoa. A total of 60 ejaculates were analysed. GWF was compared with glass wool filtration/swim-up (GWF-SU) by using aliquots from the same semen samples to increase the precision of the comparison and to establish the cumulative effect of these two semen preparation methods on the morphology of the recovered spermatozoa. Sperm parameters were examined in native semen, in semen preparation samples after GWF and GWF-SU. The mean percentages for motility, morphology and velocity were improved significantly over those in fresh semen only when GWF-SU was used. GWF alone resulted only in a significantly higher recovery of motile spermatozoa. In semen preparation, 10% of spermatozoa with normal morphology appeared to be the cut-off point as there was a significantly higher recovery in fresh semen samples containing > 10% morphologically normal spermatozoa after GWF-SU. Outcome of IVF-ET following preparation with GWF-SU showed better results in comparison to the swim-up procedure alone, though this difference was not statistically significant. The cut-off point was also > 10% morphologically normal spermatozoa. Improvement in all aspects of IVF-ET occurred when native semen contained > 10% morphologically normal spermatozoa. It is concluded that GWF alone did not produce significantly better results but, in combination with swim-up, it resulted in significantly better sperm morphology and in an improved outcome of IVF-ET for fresh semen samples with > 10% morphologically normal spermatozoa.

The value of semen characteristics and tests of sperm function in selecting couples for intra-uterine insemination

In order to improve the selection of couples for intrauterine insemination (IUI) because of longstanding primary infertility of alleged male origin, we have performed a prospective study measuring conventional and advanced analysis of sperm characteristics, the hypoosmotic swelling test, the Shorr stain, the acidified aniline blue stain and alpha-glucosidase activity in seminal plasma, of 89 couples with no demonstrable abnormality of the female partner. Twenty-four couples attained spontaneous conception, 23 were successful within six cycles of IUI, and 42 remained without conception in spite of IUI during six unstimulated cycles. The proportion and concentration of spermatozoa with progressive motility was significantly lower (P < 0.01) in the successful IUI cases than in the couples attaining spontaneous conception, and the lower quartile value was lower in the former than in the latter. There were less pregnancies among IUI treated couples when sperm concentration and motility were within the range of normal fertile men, or when the concentration of white blood cells was elevated. More pregnancies occurred when markers of epididymal function, namely the result of the Shorr stain and alpha-glucosidase measurement, were normal. Total progressive motility and the result of the Shorr stain were the only independent variables selected by logistic regression to discriminate between successful and failed IUI cases. It is concluded that only a limited group of couples may benefit from IUI.

Strict criteria for the evaluation of human sperm morphology and its impact on assisted reproduction

Sperm morphology abnormalities can be identified in a large proportion of patients with failed and delayed fertilization when assessing this parameter with strict criteria. Statistical analyses of a large IVF population confirm that, in patients with severe teratozoospermia, fertilization rates can be enhanced in many cases by increasing insemination concentration. However, implantation rates are impaired, thereby affecting the ability of these patients to establish a viable pregnancy. Data from couples undergoing controlled ovarian stimulation/intrauterine insemination seem to support the use of strict morphology as a predictor of outcome in this setting, too. Although a descriptive parameter, sperm morphology assessed by strict criteria can be used as a biomarker of sperm dysfunction(s). These dysfunctions are multiple and include abnormalities of motion parameters, poorer capacity to bind to homologous zona pellucidae and penetrate zona-free eggs, and low incidence of spontaneous and induced acrosome reaction. At a cellular level, poor morphology is associated with a higher content of creatine kinase and impaired capacity to undergo appropriate changes in intracellular calcium concentration. Whether nuclear/DNA abnormalities are present still remains to be fully determined. A definitively objective evaluation of morphology based on these criteria may allow all centres specializing in assisted reproduction to analyse semen in a homogeneous fashion.

Value of sperm morphology assessed by strict criteria for prediction of the outcome of artificial (intrauterine) insemination

The purpose of this study was to investigate the relationship between sperm parameters and the outcome of artificial (intrauterine) insemination (IUI). One hundred and twenty-six patients undergoing 395 consecutive IUI cycles in a 1-year period in our institution were studied. In all cases, controlled ovarian stimulation and hCG-timed IUI were performed, followed by progesterone supplementation of the luteal phase. In 86 patients, (243 cycles) the husband's sperm was utilized, whereas in 40 couples (152 cycles), donor sperm was used due to severe male factor infertility. Among the sperm parameters of the original ejaculate, % normal morphology (assessed by strict criteria) was the most significant predictor of pregnancy (stepwise regression analysis, P = 0.003). Using logistic regression, morphology was the best predictor of pregnancy (r = 0.12); linearity of movement significantly enhanced the predictive value of morphology alone (r = 0.17, P = 0.004). Overall, the pregnancy rates were significantly higher (P = 0.01) in cases with > or = 14% normal morphology (15% per cycle) compared to cases with < 14% normal morphology (7% per cycle). This threshold level for morphology is in agreement with previously published IVF results. These results underscore the significance of sperm morphology assessed by strict criteria as a predictor of pregnancy outcome in the IUI setting.

Development of an objective and manual technique to study the human sperm morphology

The aim of the present paper is to present results of sperm morphology using an objective and manual technique by video image. Experiment 1:252 spermatozoa heads were measured in a microscope and in a monitor by each of three independent observers. The results allowed the calibration of an acetate overlay according to the WHO guideline and following the strict criteria. Experiment 2: 10 morphology slides from normal and abnormal patients were studied. These slides were evaluated by three independent observers, each counting at least 200 cells using the calibrate acetate overlay. In the first experiment the calculation of the regression out-put was: constant: 0.24, standard error of Yc: 0.04, R squared: 0.96, X coefficient: 0.36, and standard error of the coefficient: 0.03. In the second experiment, it can be seen that the differences among the operators are not statistically significant and therefore the experiment is independent from the operator. In conclusion, the methodology developed in this paper for the evaluation of morphology would be a good tool for the evaluation of human sperm morphology.

Morphometric analysis of human sperm morphology

Fourteen morphological forms of human spermatozoa were analysed morphometrically using semi-automated image analysis techniques. Five basic (area, perimeter, length, width and mass) and five derived (ratio, length minus width, ellipticity, form and total mass) parameters were considered. Statistical analysis showed differences among all 14 types of human sperm heads. Basic parameters describing the size and shape were enough to distinguish most of the categories, whereas derived parameters as well as parameters dependent on stain intensity, were demonstrated to be useful for the discrimination of some morphological categories. The fact that statistical analysis showed differences among all 14 sperm types provides evidence for the reliability of our morphological classification. These results show that morphometry can be used for the fine study of sperm morphology and may serve as a database for future work dealing with sperm classification. As this is a pilot study to assess methodology, further studies will be required to validate the method in terms of its application and usefulness in assessing the fertilizing potential of human spermatozoa.

Sperm morphology as diagnosed by strict criteria: probing the impact of teratozoospermia on fertilization rate and pregnancy outcome in a large in vitro fertilization population

OBJECTIVE

To investigate the predictive value of sperm morphology assessed by strict criteria on IVF outcome.

DESIGN

Retrospective analysis of all IVF cycles (January 1987 to December 1992).

MAIN OUTCOME MEASURES

All patients were assigned to one of three groups based on sperm morphology: P-pattern (< 4% normal forms), G-pattern (4% to 14% normal forms), and N-pattern (> 14% normal forms). Morphology pattern was related to other semen characteristics and IVF outcome.

RESULTS

Despite corrective measures at oocyte insemination, the fertilization rate was significantly different among the three morphology groups, P < G < N. N-pattern sperm produced a mean fertilization rate over 85% regardless of low motility or concentration. In a cohort study, P-pattern cycles produced a lower implantation rate and lower ongoing pregnancy rate, independent of the lower fertilization rate.

CONCLUSIONS

Strict morphology is an excellent biomarker of sperm fertilizing capacity, independent of motility and concentration. P-pattern sperm may denote a poorer prognosis for establishing a pregnancy, even after a satisfactory fertilization rate is achieved.

Sperm function and its manipulation for microassisted fertilization

Comprehension of the intricate complexities of sperm function is clearly crucial to the success of attempts to manipulate it for the purposes of assisted conception. This is particularly important when considering various procedures for microassisted fertilization since these bypass critical physiological events that are mandatory for normal fertilization, to varying degrees. Methylxanthine derivatives such as pentoxifylline are useful agents for the management of oligoasthenozoospermic patients. This is particularly so for procedures such as SUZI where adequate motility of spermatozoa injected into the perivitelline space is crucial for fusion with the vitelline membrane to achieve fertilization. The generation of minute concentrations of reactive oxygen species in vitro may prove to be a valuable technique in this respect, in the light of recent evidence for their involvement in capacitation and hyperactivation. Induction of the acrosome reaction by non-invasive, non-toxic agents should markedly improve success rates for microassisted fertilization. Acrosin appears to play a central role in this and, therefore, it would seem prudent to monitor levels of acrosin activity in samples of spermatozoa used in assisted conception procedures. With respect to microassisted fertilization, the potential to select recently acrosome-reacted spermatozoa coated by activated acrosin promises to be a major improvement. Current methods employed for determination of the fertilization potential of spermatozoa are clearly inadequate (Polansky and Lamb, 1988; Aitken, 1990). In fact, the prevailing evidence suggests that no single parameter of sperm function reflects this potential (Zaneveld and Jeyendran, 1988). Therefore, we have both a scientific and a moral responsibility to investigate these processes further. Subsequently, we should be in a position to identify individual gametes with the potential for fertilization and so utilize procedures that result in maximal fertilization rates with minimal risk of polyploidy or abnormality.

Influence of three different preparation techniques on the results of human sperm morphology analysis

Using 158 unselected semen samples the present study has analysed how the results of sperm morphology assessment were influenced by different techniques for preparing the slides for microscopic assessment. All three techniques compared, the Papanicolaou stain (PAP), the Shorr stain (SHO) and the 'wet preparations' protocol (WET) are currently recommended by the World Health Organization for use in andrology laboratories. Mean percentages of morphologically normal spermatozoa were identical on PAP and SHO slides (31.1%), but were significantly lower in wet preparations (12.3%). Wide divergence of results obtained with the three different methods was also found with respect to the percentage of sperm with head, midpiece and tail defects and two 'indices of teratozoospermia'. For the majority of parameters assessed, linear regression analysis revealed a poor correlation between evaluations of PAP, SHO and WET slides (r values ranging from 0.01 to 0.87). We conclude that only one standard method should be recommended for the preparation of morphology slides in order to ensure inter-laboratory comparability of results and to enhance the value of sperm morphology analysis for predicting fertility.

Effect of semen characteristics on pregnancy rate in a gamete intrafallopian transfer program

The aim of this study was to evaluate the influence of sperm morphology, swim-up concentration, and insemination volume on pregnancy outcome in patients undergoing gamete intrafallopian transfer (GIFT) treatment in whom the male partner had a morphology of less than 14%. Only patients who received four oocytes were entered into this study (n = 103). In all cases the swim-up procedure time was standardized to 1 h and the insemination concentration was standardized to 500,000 per oviduct. There was no significant difference in pregnancy rate when normal morphology, swim-up concentration, or insemination volume were used as predictors. In the P pattern group (< 4% normal forms) only four of the 28 (14%) patients had ongoing pregnancies, whereas in the G pattern group (5% to 14% normal forms) 16 out of 75 (21%) had ongoing pregnancies (P vs G, p > 0.05; not significant). The fertilization rate among excess oocytes in the P pattern group was 18% but was 39% (p < .0001) in the G pattern group. When an attempt was made to compensate for low morphology by increasing insemination concentration no significant difference in the pregnancy rate between the P and G pattern groups in the GIFT program was recorded. This was not the case when the in vitro fertilization rate was used as an endpoint. Insemination volume and swim-up concentration played no role in pregnancy rate.

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 of the hypo-osmotic swelling test in relation with advanced methods of semen analysis

The hypo-osmotic swelling test was claimed to assess an independent functional characteristic of human spermatozoa bearing relevance to their fertilizing capacity. To test this claim, we have studied the relationship between the result of the hypo-osmotic swelling test with that of conventional semen analysis and sperm motility patterns, the semen content of adenosine triphosphate, the staining pattern to acidified aniline blue, and the zona-free hamster oocyte test. The result of the HOS test is significantly correlated with all sperm characteristics except for the aniline blue stainability and the hamster oocyte test. The capacity of spermatozoa to react in a hypo-osmotic environment expresses the same functional information as the viability test using eosine staining. It is concluded that the hypo-osmotic swelling test does not add relevant information to that obtained by routine sperm analysis with regards to the fertilizing potential of semen.

Correlations between follicular fluid steroid analysis and maturity and cytogenetic analysis of human oocytes that remained unfertilized after in vitro fertilization

OBJECTIVE

Is there any correlation between follicular fluid (FF) steroid levels and the occurrence of cytogenetic abnormalities in unfertilized human oocytes?

DESIGN

Cytogenetic analysis was carried out on 397 oocytes, and the steroid content of 104 corresponding FF was analyzed using high-pressure liquid chromatography. Ovarian stimulation was performed by clomiphene citrate and human menopausal gonadotropin (hMG) or by hMG combined with a gonadotropin-releasing hormone agonist (GnRH-a) pretreatment.

RESULTS

Oocyte maturity was correlated with an increasing FF progestin content and a significant decrease of androstenedione (A) levels. Chromosomal analysis revealed 84 of all oocytes to be abnormal (polyploid or aneuploid and/or prematurely condensed chromosomes present). In this group, A levels and A to estradiol ratios were significantly higher. Although progestin levels were higher in GnRH-a/hMG cycles, the incidence of oocyte normality was not different between the two stimulation schemes. More abnormal oocytes were found in patients with good sperm morphology.

CONCLUSIONS

Oocyte abnormality correlates with higher A levels in the corresponding FF. Oocyte fertilization is also determined by intrinsic oocytic factors other than maturity.