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PubMed2002

New frontiers in the treatment of male sterility.

Male factor responsibility in couple infertility has been exponentially increasing in recent years, due both to improved diagnostic techniques and to the important role of lesive factors, mainly environmental, on reproductive male function. Therefore, male infertility therapy is one of the most challenging topics of modern clinical medicine. Unfortunately, however, 30% of cases of male infertility must still be classified as "idiopathic." In these cases, no "causal" treatments can be used but only empiric treatments. These are lacking of an etiopathogenetic basis, and often result from theoretical concepts without a proven statistical effectiveness. These facts have somehow allowed the explosive development of the assisted reproduction techniques (ART). Andrologist's therapeutic strategies have so changed and are no longer aimed, as in the past, to achieve an increase in the spermatozoa number, but rather to improve the "quality" of semen, that is, the "fertility potential."

Bacterial Infections↗

PubMed2004

Antisperm antibodies modify plasma membrane functional integrity and inhibit osmosensitive calcium influx in human sperm.

BACKGROUND: The hypo-osmotic swelling (HOS) test evaluates the ability of the functional sperm plasma membrane to stretch following cell swelling when exposed to hypo-osmotic solutions. Sperm samples with low HOS scores show low fertilization and pregnancy rates during assisted reproductive techniques, though data are controversial. The aim of this study was to compare the results of the HOS test in a group of normozoospermic men with those in a group of subjects affected by autoimmune infertility due to the presence of antisperm antibodies (ASA) bound to the sperm surface. METHODS: Sperm from normozoospermic and from infertile subjects affected by autoimmune infertility were exposed to hypo-osmolar conditions to verify the effects on intracellular calcium concentrations and acrosome reaction. RESULTS: Sperm samples from infertile men with ASA showed HOS test scores that were significantly lower than those of normozoospermic subjects despite similar sperm viability percentages. Sperm with ASA bound to their plasma membrane showed a reduced rise in intracellular calcium concentrations and acrosome reaction after hypo-osmotic challenge with respect to sperm from normozoospermic subjects without ASA. CONCLUSIONS: Infertile subjects with ASA have a reduced sperm plasma membrane functional integrity that could explain, at least in part, the low fertilization and pregnancy rates observed in these subjects during assisted reproductive procedures. Evaluation for the presence of ASA in all sperm samples showing low HOS test scores in the presence of normal sperm viability percentages is suggested.

Acrosome Reaction↗

PubMed2006

[Endometrial receptivity: numerical classification to successful prognosis in assisted reproduction programs].

BACKGROUND: Currently, the most precise way of predicting uterine receptivity is the histopathological study through endometrial biopsy. Endometrial morphology and thickness are the factors most strongly associated with better pregnancy rates. OBJECTIVE: To evaluate the prediction value of a numerical grade to predict pregnancy in patients exposed to assisted reproductive techniques. PATIENTS AND METHODS: 22 cycles of in vitro fertilization were made at the Instituto para el Estudio de la Concepción Humana in Monterrey, Nuevo León, from June 2003 to January 2004. We evaluated and categorized: endometrial thickness and morphology, vascularity, miometrial ecogenicity, and uterine artery blood flow (including pulsatility and resistance indexes, presence of protodyastolic nicks, and telediastolic flow). The final numerical grade result from the sum of the individual values obtained for each factor. RESULTS: We included 22 cycles of 20 patients. The general pregnancy and implantation rate was of 40 (8/20) and 26% (17/65) per cycle, respectively. The most common diagnosis was tube occlusion (28%), followed by masculine sex (24%), endometriosis (14%), anovulation (14%), and inexplicable (14%). There were no statistical differences among the pregnant and non-pregnant groups regarding: age, hormonal profile (FSH and estradiol, basal and at the tenth day), total of recombinant FSH unities, follicles > or = 14 mm the day of applying human chorionic gonadotropin, aspired eggs, fertilization index, and transferred embryos. CONCLUSIONS: Endometrial maturity is essential for implantation during an assisted reproductive procedure.

Adult↗

PubMed2006

Somatic cytogenetic and azoospermia factor gene microdeletion studies in infertile men.

The objective of the present study was to determine the frequency of somatic chromosomal anomalies and Y chromosomal microdeletions (azoospermia factor genes, AZF) in infertile males who seek assisted reproduction. These studies are very important because the assisted reproduction techniques (mainly intracytoplasmic sperm injection) bypass the natural selection process and some classical chromosomal abnormalities, microdeletions of AZF genes or some deleterious genic mutations could pass through generations. These genetic abnormalities can cause in the offspring of these patients male infertility, ambiguous external genitalia, mental retardation, and other birth defects. We studied 165 infertile men whose infertility was attributable to testicular problems (60 were azoospermic, 100 were oligospermic and 5 were asthenospermic). We studied 100 metaphases per patient with GTG banding obtained from temporary lymphocyte culture for chromosomal abnormality detection and performed a genomic DNA analysis using 28 Y chromosome-specific sequence-tagged sites for Y AZF microdeletion detection. Karyotyping revealed somatic anomalies in 16 subjects (16/165 = 9.6%). Of these 16, 12 were in the azoospermic group (12/60 = 20%) and 4 were in the oligospermic group (4/100 = 4%). The most common chromosomal anomaly was Klinefelter syndrome (10/165 = 6%). Microdeletions of AZF genes were detected in 12 subjects (12/160 = 7.5%). The frequencies detected are similar to those described previously. These results show the importance of genetic evaluation of infertile males prior to assisted reproduction. Such evaluation can lead to genetic counseling and, consequently, to primary and secondary prevention of mental retardation and birth defects.

Chromosome Deletion↗

PubMed1990

Comparison of different ovarian stimulation protocols for gamete intrafallopian transfer in patients with minimal and mild endometriosis.

Three different stimulation protocols were tested in patients affected by stage I and II endometriosis with no other causes of infertility, and scheduled for the gamete intrafallopian transfer technique. In two protocols a gonadotropin hormone-releasing hormone analog was used. The analog was started 6 months before stimulation in the former and along with the exogenous gonadotropin in the latter. Patients receiving only gonadotropin served as controls. Sixty patients were selected for this study; 55 reached laparoscopy. Whereas patients receiving either gonadotropin alone or simultaneous analog and gonadotropin had similar pregnancy rates, this was much higher in the patients undergoing a prolonged, medically induced hypoestrogenism. Prolonged analog pretreatment before ovarian stimulation may give better chances of success in endometriosis patients undergoing assisted reproduction techniques.

Adult↗

PubMed1998

Case-based reasoning in IVF: prediction and knowledge mining.

In vitro fertilization (IVF) is a medically-assisted reproduction technique, enabling infertile couples to achieve successful pregnancy. Given the unpredictability of the task, we propose to use a case-based reasoning system that exploits past experiences to suggest possible modifications to an IVF treatment plan in order to improve overall success rates. Once the system's knowledge base is populated with a sufficient number of past cases, it can be used to explore and discover interesting relationships among data, thereby achieving a form of knowledge mining. The article describes the TA3IVF system--a case-based reasoning system which relies on context-based relevance assessment to assist in knowledge visualization, interactive data exploration and discovery in this domain. The system can be used as an advisor to the physician during clinical work and during research to help determine what knowledge sources are relevant for a treatment plan.

Artificial Intelligence↗

PubMed2000

Laparoscopy in the "normal" infertile patient: a question revisited.

STUDY OBJECTIVE: To determine the prevalence of reproductive pathology in a group of infertile women thought to be at low risk for altered pelvic anatomy. DESIGN: Retrospective chart review and follow-up (Canadian Task Force classification II-2). SETTING: Academic-affiliated, private reproductive endocrinology practice. PATIENTS: One hundred infertile women. INTERVENTION: Diagnostic and/or therapeutic laparoscopy. MEASUREMENTS AND MAIN RESULTS: Of 100 patients with a negative reproductive work-up up to the point of laparoscopy, 68 had pathology of reproductive significance: intrinsic tubal disease 24, peritubal adhesive disease 34, and endometriosis 43, some in combination. Laparoscopy was especially helpful in establishing treatment protocols for older women, who were referred for assisted reproductive techniques earlier than otherwise might have been the case. Women conceived after hormone therapy and after operative intervention. Although the hysterosalpingogram was read as normal in all women, tubal disease was diagnosed laparoscopically, independent of endometriosis, in 27 patients, with 2 having complete obstruction. Endometriosis stage I-II was found in 22 patients, stage III in 13, and stage IV in 6. CONCLUSION: Even in women thought to be at low risk for significant pelvic pathology affecting reproduction, the yield was high. Although some pregnancies were achieved after operative intervention, frequently laparoscopy was helpful in making a decision to go to assisted reproductive technology, particularly when infertility had been of long duration and in older women. Frequently the degree of pathology was such that a full operating suite was necessary to provide adequate instrumentation and anesthesia for operative intervention, which would not have been the case with office laparoscopy.

Adult↗

PubMed1993

Psychological considerations of anonymous oocyte donation.

This study involved 50 patients interviewed in conversations with a psychologist. It was found that it was possible to characterize the kind of couples using assisted reproductive techniques in terms of diagnostic and psychological profile. Other observations included the repercussions of this action on the couples' stability in case of failure or success, the desire for children and the plans concerning them, the secrecy theme and questions arising from the practice of anonymous or non-anonymous oocyte donation. The relationship between recipients and donors, as well as the specific relationship between couples and their consultants, were also examined. It is concluded that the problems encountered differ according to the infertility diagnosis. Donor anonymity allows oocyte recipients to impose their own identity patterns onto the future child and to introduce him/her in an unbiased way to their own lives. Artificial techniques to assist in the conception of a child do not appear to interfere with the couple's relationship and their desire for a child, which remains constant for each member of the couple.

Antineoplastic Agents↗

PubMed2004

Inter-sample variability in post-thaw human spermatozoa.

Semen cryopreservation is a useful tool for preserving fertility in men who have been diagnosed with cancer and will undergo chemotherapy, radiotherapy or testicular surgery. Semen is also commonly cryopreserved prior to its use in assisted reproductive techniques such as in vitro fertilization and intracytoplasmic sperm injection. The post-thaw quality of banked sperm can vary, which may negatively affect fertilization rates. The objective of our study was to assess the pre-freeze and post-thaw variability of sperm parameters in patients who used our sperm banking services. Multiple samples obtained after a short period of sexual abstinence were examined for variation in sperm characteristics. Semen samples showed a high degree of post-thaw inter-sample variability in sperm motility, motion characteristics, and percentage cryosurvival rate compared with the pre-freeze inter-sample variability. Further research is necessary to understand the mechanism(s) responsible for this variability. This may also assist clinicians utilize semen samples with optimum semen quality in ART procedures.

Cell Survival↗

PubMed2006

[Young women with atypical endometrial hyperplasia or endometrial adenocarcinoma stage I: will conservative treatment allow pregnancy? Results of a French multicentric survey].

OBJECTIVES: To analyse the carcinological and obstetrical results of young women with atypical endometrial hyperplasia or endometrial adenocarcinoma, treated in a conservative way to allow pregnancy. PATIENTS AND METHODS: A retrospective analysis of 13 cases (5 adenocarcinomas and 8 atypical hyperplasias) followed in 8 French centers between 1997 and 2004. RESULTS: After 4.6 months of conservative treatment, there were no residual lesions in 61.5% of the cases. Progestatives seem to be the most effective treatment. Tumoral regression makes it possible to plan a pregnancy, with childbirth in 25% of the cases. In these frequently infertile patients, all the techniques of assisted reproduction can be used. Recurrences are not rare after hormonal treatment (37.5%), so, total hysterectomy is justified after delivery. DISCUSSION AND CONCLUSION: Conservative treatment for young women with atypical endometrial hyperplasia or endometrial adenocarcinoma stage I can be considered in some cases to enable pregnancy.

Adenocarcinoma↗

PubMed1999

Clinical aspects of ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome (OHSS) is characterized by massive transudation of protein-rich fluid (mainly albumin) from the vascular space into the peritoneal pleural and to a lesser extent to the pericardial cavities. The intensity of the syndrome is related to the degree of the follicular response in the ovaries to the ovulation inducing agents. OHSS is still a threat to every patient undergoing ovulation induction. The pathophysiology of OHSS is of extreme importance in the face of the increased use of ovulation induction agents as well as the development of sophisticated assisted reproductive techniques. The correlation found between plasma cytokine activities and the severity of OHSS suggests that plasma cytokines may be involved in the pathogenesis of OHSS and may serve as a means of monitoring the syndrome during the acute phase and throughout convalescence. The interactions between cytokine and non-cytokine mediators of the syndrome, such as the renin-angiotensin system and vascular endothelial growth factor were recently clarified. Awareness of possible mechanisms and factors in the pathophysiology of OHSS will hopefully provide opportunities to design specific treatment regimens effective for both prevention and treatment of this potentially fatal iatrogenic condition. Among IVF patients with severe and critical OHSS, pregnancy rates, multiple gestations, miscarriage, preterm premature rupture of the membranes, prematurity, and low birth weight rates are significantly higher than those reported previously for pregnancies after assisted conception. The incidence of other obstetrical complications, as well as congenital malformations and Cesarean section rates are not significantly different.

Adult↗

PubMed2006

Y chromosome and male infertility: update, 2006.

Male factor infertility accounts for about half the cases of couple infertility and in around 50% of cases its etiology remains unknown. Molecular genetic techniques have unveiled a number of etiopathogenetic factors, including microdeletions of the Yq. Y chromosome microdeletions removing the AZoospermia Factor (AZF) regions are the most frequent molecular genetic causes of oligo/azoospermia. The intense effort of many laboratories contributed to a better understanding of the clinical significance of this genetic anomaly and to the identification of fertility candidate genes in the AZF regions. Important progress has been made on the structure of the Y chromosome and the mechanism of deletion. Studies aimed to define a predisposing genetic background for Yq deletions were not successful, perhaps due to the low number of patients analyzed so far. The screening for Yq deletions became a routine diagnostic test that provides an etiology for spermatogenic disturbances, and assess in the prognosis for testicular sperm retrieval according to the type of deletion. Assisted reproductive techniques represent an efficient symptomatic therapy for men bearing Y microdeletions, however, this genetic defect is transmitted to the male offsprings, affecting their fertility. Future studies should focus on understanding the biological function of AZF genes which is an essential step for the development of more appropriate and knowledge-based therapies.

Chromosome Deletion↗

PubMed2001

Twinning rate in a sample from a Brazilian hospital with a high standard of reproductive care.

CONTEXT: Epidemiological studies on twin births have been motivated mostly by the positive correlation between twinning rate and human fertility, prematurity, low birth weight, increased risk of infant death and long term risk for morbidity. OBJECTIVE: This paper intends to estimate the incidence of multiple births in a private hospital in Brazil with a high standard of reproductive care, and to evaluate the effects of maternal age, gestation order and assisted fertilization on twinning rate. DESIGN: Retrospective analysis. SETTING: First-class tertiary private hospital, São Paulo, Brazil. PARTICIPANTS: The multiple birth rate was investigated among 7,997 deliveries from 1995 to 1998, including 7,786 singletons, 193 twins, 17 triplets and one quadruplet. RESULTS: The rates per 1,000 dizygotic and monozygotic pairs and for triplets were estimated as 19.51, 4.50 and 2.13, respectively. The dizygotic and triplet rates were the highest observed in Brazil up to the present day. The twinning rate among primigravidae older than 30 years was very high (45.02 per 1,000) and was due to a disproportionately high frequency of dizygotic pairs. The triplet rate was also very high among the mothers of this age group (5.71 per 1,000). These facts are strong indicators that these women were the ones most frequently submitted to assisted reproductive techniques. The mean maternal age of the studied population was about six years higher than that estimated for mothers in the general population of southeastern Brazil. Primigravidae aged under 30 years as well as multigravidae showed similar twinning rates, which were almost 20 per 1,000. Among the deliveries of multigravidae older than 30 years, an unusually high frequency of monozygotic twins was observed (7.04 per 1,000), probably as a consequence of the residual effect of long-term use of oral contraceptives. CONCLUSIONS: The dizygotic twinning rate increased from 13.51 to 28.98 per 1,000 over the four years studied, with the twinning rate for primigravidae over 30 years old in 1998 being twice that observed in 1995. The mean maternal age was also high during this period, but the extremely high increase in twinning rate observed cannot be attributed solely to this variable. Assisted fertilization seems to be the most probable cause of this unusually high twinning rate.

Adult↗

PubMed1998

[The ICSI (Intracytoplasmic Sperm Injection)].

ICSI (Intracytoplasmic Sperm Injection) is the latest known assisted reproduction technique (ART) and it already appears to be mature. In fact the analysis of the results presented by the researchers over the years has shown that the most specific indication for this ART is the sterility of the couple with serious male pathology, up to ejaculatory azoospermia where it is possible to perform MESA, PESA or TESE. Any kind of sterility could be solved with ICSI whose only limit presently known is the high technology and therefore high costs involved. The percentage of oocytes that undergo ICSI without being damaged varies from 87% to 94% and the percentage of fertilization varies from 33% to 71%. The transfer rate is 59-100%. The rate of pregnancies per couple ranges from 12% to 40% of the couples, from 11% to 41% for the transfers. Since abortions are similar to the values of the normal population (10-15%), ICSI is actually the assisted fertilization technique with the highest incidence of pregnancies and "take home babies". The percentage incidence of the two sexes, of the malformations and the typologies of malformations corresponds to those observed in the population with spontaneous pregnancies. Since there is no natural selection of the gametes in ICSI, one may be sure that when spermatozoa with any kind of pathology are injected, the pregnancy does not take place at all.

Cytoplasm↗

PubMedDate not supplied

Rethinking gamete/embryo isolation and culture with microfluidics.

IVF remains one of the most exciting modern scientific developments and continues to have a tremendous impact on people's lives. Since its beginnings, scientists have studied and critically analysed the techniques in order to find ways to improve outcomes; however, little has changed with the actual technology and equipment of IVF. Semen is still processed in test tubes and fertilization and culture still occurs in culture dishes. New technological possibilities exist with the burgeoning advancement of microfluidic technology. Microfluidics is based on the behaviour of liquids in a microenvironment. Although a young field, many developments have occurred which demonstrate the potential of this technology for IVF. In this review, we briefly discuss the physical principles of microfluidics and highlight some previous utilizations of this technology, ranging from chemical analysis to cell sorting. We then present the designs and outcomes for microfluidic devices utilized thus far for each step in IVF: gamete isolation and processing, fertilization, and embryo culture. Finally, we discuss and speculate on the ultimate goal of this technology--development of a single, integrated unit for in-vitro assisted reproduction techniques.

Cell Culture Techniques↗

PubMed1995

A method of human semen centrifugation to minimize the iatrogenic sperm injuries caused by reactive oxygen species.

Current techniques of sperm preparation for in vitro fertilization or intrauterine insemination require centrifugation of human semen to separate spermatozoa from the seminal plasma. Centrifugation increases reactive oxygen species (ROS) formation in semen. Moreover, high levels of ROS are associated with sperm membrane injury through spontaneous lipid peroxidation, which may alter sperm function. We investigated the relationship between centrifugation variables (time and g-force) and ROS production to establish an optimal centrifugation protocol for sperm preparation techniques. Semen from 38 men (24 patients and 14 normal volunteers) was evaluated for the formation of ROS before centrifugation and after centrifugation at 200 g for 2 or 10 min and after 500 g for 2 or 10 min. The absence of white blood cells in semen which can also produce ROS was determined with the myeloperoxidase technique (Endtz test). All specimens were negative (< 1 x 10(6)/ml) by the Endtz test. The formation of ROS was measured by chemiluminescence. ROS formation was regarded as high (positive) when the chemiluminescence response was at least 10 x 10(4) counted photons/min (cpm). The sperm concentration in each sample was adjusted to 15-20 x 10(6) cells/ml before analysis. Eight specimens (7 patients and 1 donor) exhibited high levels of ROS before centrifugation. All 8 showed further, significant increases in ROS formation regardless of g-force or time. The increase in ROS was significantly less when semen was centrifuged for 2 as compared to 10 min (p < 0.001). Six specimens previously ROS-negative became ROS-positive after centrifugation for 10 min at 200 and 500g. We conclude that the time of centrifugation is more important than g-force for inducing ROS formation in semen. Based on these results, we recommend a shorter centrifugation period in the preparation of sperm for assisted reproductive techniques.

Centrifugation↗

PubMedDate not supplied

[Microdeletion of chromosome Y in male infertility: role of the DAZ gene].

Microdeletions of the Y chromosome represent the most frequent cause of male infertility, being responsible for 10-15% of cases of azoospermia or severe oligozoospermia. Such mutations localize in one or more loci named azoospermia factor (AZF) a, b and c. Mutations more frequently involve the DAZ gene in AZFc, and could determine both azoospermia and severe oligozoospermia. It is therefore difficult to find a clear relationship between genotype and phenotype. DAZ is present in multiple copies in AZFc, and this causes the gene to be difficult to analyze. In fact, polymerase chain reaction, the principal technique utilized for detection of the deletions, cannot distinguish among the different copies of the gene. Furthermore, it is not clear if all the DAZ copies are expressed in the testis, and other genes, such as CDY1, map in AZFc; therefore their alteration may play a role in determining the phenotype. In this review we report the current knowledge on the function of the Y chromosome in human spermatogenesis. In particular we analyze some of our experimental studies on the role of the DAZ gene family. Expression studies allowed us to clarify that an altered expression of DAZ might cause infertility in patients with severe testiculopathies. Furthermore, we describe for the first time a deletion not involving all the DAZ copies in a patient with severe hypospermatogenesis and we clarify that CDY1 is not involved in the testicular damage observed in patients with deletions of DAZ. These studies elucidate the role of DAZ and have important clinical consequences in the diagnostic and therapeutic approach of the infertile patient, above all when he is a candidate for assisted reproduction techniques, due to the possibility of transmitting the genetic alteration to the offspring.

Chromosome Deletion↗

PubMed1995

The use of hemizona assay in the evaluation of the optimal sperm preparation technique.

The objective of the study was to evaluate the benefit of different sperm preparation methods by using the hemizona assay. A total of 58 men admitted to the male infertility clinic for evaluation were tested by routine semen analysis and hemizona assay. Five different techniques (swim-up, TEST-yolk buffer, Percoll, pentoxifylline and progesterone) were used for preparation of sperm suspensions. The effect of these treatments on the sperm-binding capacity using the hemizona assay was assessed. The routine swim-up preparation was used as the reference method. Of the four preparation methods, only the TEST-yolk buffer and pentoxifylline exhibited an overall statistically significant improvement in sperm-binding capacity in comparison with the swim-up preparation method (P = 0.01 and 0.001 respectively). Following preparation with Percoll and progesterone there was no change in the mean value of binding capacity, compared with swim-up. However, examination of the effect of the four treatments on each specimen individually yielded a diversity in the response, e.g. having the capability to enhance, damage or be ineffective in sperm binding capacity. The results support the conclusion that in-vitro sperm preparation methods can affect sperm binding to the zona pellucida. Since there is a diversity in the response of sperm samples to different treatments, the hemizona assay can be used in selecting the optimal sperm preparation method prior to its use for assisted reproductive techniques. This is advocated mainly for the 'male factor' group.

Cell Separation↗