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At least 433 records · Page 24Linked to original sources
PubMed2003

Birth after intracytoplasmic injection of epididymal sperm from a man with congenital bilateral absence of the vas deferens who had a robertsonian translocation.

OBJECTIVE: To present the first case of an infertile male with azoospermia related to a congenital bilateral absence of the vas deferens (CBAVD), in which mutations within the cystic fibrosis transmembrane conductance regulator (CFTR) gene coexist with a robertsonian translocation. DESIGN: Case report. SETTINGS: A university hospital. PATIENT(S): A 34-year-old male with a 2-year history of primary infertility. INTERVENTION(S): Lymphocytic karyotype, polymerase chain reaction (PCR) and allele oligonucleotide-specific hybridization (ASO), microsurgical epididymal sperm aspiration (MESA), and intracytoplasmic sperm injection (ICSI). MAIN OUTCOME MEASURE(S): Physical examination and semen analysis. RESULT(S): Semen analyses revealed azoospermia and a well-recognized obstructive phenotype. Analysis of the CFTR gene revealed a compound heterozygosity for a 2184 del A + 2183 A --> G mutation on one allele and the 5T variant within the polypyrimidine tract of intron 8 on the other allele. Cytogenetic analyses revealed a t(13;14)(q10;q10) robertsonian translocation in the same patient. Microsurgical epididymal sperm aspiration allowed retrieval of a million mature motile spermatozoa, excluding any spermatogenic impairment secondary to the genetic abnormalities found in this patient. Epididymal sperm was used for an intracytoplasmic sperm injection program, and a normal child was born at term. CONCLUSION(S): This case illustrates that two distinct genetic defects may coexist, with a variable effect on male fertility but with important implications for genetic counseling of the future pregnancy.

Adult↗
PubMed1999

Testicular sperm extraction: comprehensive analysis with simultaneously performed histology in 1418 biopsies from 766 subfertile men.

The introduction of intracytoplasmic sperm injection (ICSI) has revolutionized treatment of male-factor infertility. Even with a single spermatozoon a pregnancy can be achieved. In cases of azoospermia due to obstruction or highly impaired spermatogenesis, spermatozoa can be retrieved directly from testicular tissue recovered by testicular biopsy followed by sperm extraction. The predictive value of histology from semi-thin sections of testicular biopsies was assessed in relation to testicular sperm extraction (TESE) results, using 1418 biopsy samples from 766 subfertile men which were evaluated simultaneously using a modified Johnsen score and an ordinal classification system for spermatozoa in TESE samples. In 655 men bilateral samples were available. Based on histological findings and TESE results, the quality of spermatogenesis in the right testes was significantly better than that in the left testes. There was a difference between the two sides in 35.7% of all patients for histology and 32.7% for TESE results. When best results from either testis were used for analysis, 76.9% of all men revealed spermatozoa in TESE preparations, although during histological evaluation of semi-thin sections only 64% of all men had shown mature spermatids. In a core group of 250 azoospermic men without anamnestic hints to obstruction and most likely to benefit from ICSI, TESE was successful in 62.8% men. Subdivision of this group dependent on follicle stimulating hormone (FSH) serum concentrations revealed that even in cases of increased FSH concentration, between 39.1 and 64.7% of men showed mature spermatids in their TESE samples. A subset of 70 azoospermic men from the main sample with symptoms and history suggestive of an obstruction and considered as positive controls showed a positive TESE result in all patients. The histology had failed to predict this in 2.9% of all cases. Nevertheless, in five men an early stage of testicular tumour (carcinoma in situ = CIS) was detected. Two of these males suffered from bilateral CIS. This reflects a prevalence of 0.7% testicular malignancy in the group of patients without a history of excurrent duct obstruction. The data demonstrate that a trial TESE with histology based on the semi-thin sectioning technique is a powerful diagnostic and therapeutic procedure, which justifies the invasive nature of sperm retrieval for ICSI. In addition, the results stress the importance of bilateral biopsies to gain optimal diagnostic and therapeutic results.

Adult↗
PubMed1997

Azoospermic men with deletion of the DAZ gene cluster are capable of completing spermatogenesis: fertilization, normal embryonic development and pregnancy occur when retrieved testicular spermatozoa are used for intracytoplasmic sperm injection.

Some men with non-obstructive azoospermia harbour fully formed spermatozoa within their testicular tissue that can be used to achieve pregnancy via intracytoplasmic sperm injection (ICSI). Recently, Reijo et al. (1995) provided compelling evidence that the DAZ gene cluster is a strong candidate for one of the elusive azoospermia factors (AZF) located on the long arm of the Y chromosome. The DAZ gene cluster is deleted in 13% of azoospermic men and a small percentage of severely oligozoospermic men. Vertical transmission from father to son of AZF region deletions has also been described. Presumably these fathers were oligozoospermic. This led us to ask whether the azoospermic male with deletions of the AZF/DAZ region can also complete minimal spermatogenesis and whether any spermatozoa found could participate in fertilization, embryo development and pregnancy. Three out of six (50%) of the azoospermic men with AZF/DAZ deletions had spermatozoa identified within their harvested testicular tissue. When these spermatozoa were used for ICSI, fertilization occurred in 36% of injected oocytes. This compared favourably with testicular spermatozoa retrieved from non-obstructive azoospermic men without AZF/DAZ gene deletions. In one case, a twin conception resulted, which represents the first term pregnancy reported using spermatozoa from an AZF/DAZ deleted azoospermic male. Therefore it is necessary to take the possibility of transmission of infertility or sterility to our patients' offspring seriously when utilizing today's reproductive technologies, as spermatogenesis in men with AZF/DAZ deletions is by no means an exceptional occurrence.

Chromosome Mapping↗
PubMed2001

Involvement of oviduct in sperm capacitation and oocyte development in pigs.

An overview is presented on the structure and function of the pig oviduct in relation to sperm capacitation and oocyte development in vivo. In pigs, a functional sperm reservoir is established in the uterotubal junction-isthmus when sperm deposition occurs before ovulation. Capacitation is assumed to occur in this location, and spermatozoa progress towards the ampullary-isthmic junction at about the time of ovulation as a consequence of capacitation and hyperactivation. Preliminary data from our laboratory on viable spermatozoa retrieved from the sperm reservoir and the ampullary-isthmic junction of mated sows at pre- and periovulation oestrus showed that the largest subpopulation (60-90%) was of uncapacitated spermatozoa (using merocyanine-540), whereas 6-37% of the gated cells were capacitated spermatozoa. Incubation in a capacitation-inducing medium (bicarbonate-containing modified Brackett-Oliphant medium; mBO) for < 30 min effected capacitation readily, more markedly in ampullary-isthmic junction samples than in samples from the uterotubal junction, thereby indicating that uncapacitated spermatozoa responded to the addition of the effector bicarbonate at concentrations similar to those recorded in the periovulatory ampullary-isthmic junction in vivo. Addition of preovulatory isthmic oviductal fluid and hyaluronan under a similar incubation regimen maintained tubal sperm viability without obvious induction of capacitation. This finding indicates that, before ovulation, the intraluminal fluid of the sperm reservoir might delay sperm capacitation, perhaps because of its hyaluronan content. Evidence is presented that the sperm population in the oviduct undergoes capacitation under particular conditions in the upper tubal compartments. The diverse response of spermatozoa to capacitation stimuli helps to ensure full rates of fertilization in vivo. Data are also provided on the importance of final zona pellucida maturation in the pig oviduct to warrant proper zona pellucida reaction after sperm penetration, which would address in part the abnormal occurrence of polyspermy in in vitro fertilization of pigs.

Animals↗
PubMed2006

The effects of oxidative stress on outcomes of assisted reproductive techniques.

PURPOSE: To investigate the impact of oxidative stress on pregnancy success by monitoring malondialdehyde levels in follicular fluid. METHODS: Forty five couples were enrolled in this prospective study. Following long protocol of GnRH analogues and r-FSH treatment, oocyte retrieval and intracytoplasmic sperm injection were performed. Malondialdehyde levels were assayed by thiobarbutiric acid reacting substances test. Student's t-test and chi(2) test were used for statistical analysis. RESULTS: Patients were divided into two groups; group I (pregnancy positive, n = 20), group II (pregnancy negative, n = 25). There was no statistical significant difference in terms of age, infertility period, FSH levels on the third day, number of oocytes retrieved and fertilization rates between the two groups. Pregnancy rates were found to be decreasing in higher malondialdehyde levels. CONCLUSION: Malondialdehyde can be used as a marker of oxidative stress and a potential marker in predicting assisted reproductive techniques outcome.

Adult↗
PubMed2006

Development of neonatal mouse and fetal human testicular tissue as ectopic grafts in immunodeficient mice.

AIM: To investigate the stepwise development and germ cell gene expression in allografted neonatal mouse testes and the differentiation of immature human testicular cells in xenografted human testes. METHODS: Immunodeficient nude mice were used as hosts for allografting of neonatal mouse testes and xenografting of human fetal testicular tissues. Stepwise development and stage-specific gene expression of germ cells in allografts were systematically evaluated and parallel compared with those in intact mice by periodically monitoring the graft status with measurement of graft weight, histological analysis and determination of five stage-specific genes. Human testicular tissues from 20 and 26 weeks fetuses were used for the xenografting study. Histological analysis of xenografts was performed 116 and 135 d after the grafting procedure. RESULTS: In the allografting study, progressive increase in tissue volume and weight as well as in tubule diameter in grafts was observed; the appearance time of various germ cells in seminiferous tubules, including spermatogonia, spermatocytes, round and elongate spermatids and sperm, was comparable with that in intact donors; the initiation of gene transcription in grafts showed a similar trend as in normal mice. Graft weight ceased to increase after 7-8 weeks and degradation of grafts was observed after 5 weeks with progressive damage to seminiferous epithelium. In the xenografting study using immature human testicular tissues, graft survival and development was indicated by increasing graft weight, Sertoli cells differentiation into advanced stage, germ cells migration and location to the basal lamina and formation of a niche-like structure. CONCLUSION: The developmental course and gene expression pattern of germ cells in allografts were similar to those in intact mice. The best time point for retrieval of mouse sperm from grafts was 5-7 weeks after grafting procedure. An accelerated development of immature human testicular cells could be achieved by ectopic xenografting of human testes.

Animals↗
PubMed2001

Comparison of the outcome of intracytoplasmic sperm injection using fresh and frozen-thawed epididymal spermatozoa obtained by percutaneous epididymal sperm aspiration.

The study was conducted to compare the outcome of intracytoplasmic sperm injection (ICSI) between fresh and frozen-thawed epididymal spermatozoa retrieved by percutaneous epididymal sperm aspiration (PESA) from obstructive azoospermic men. Overall, 53 PESA procedures were performed in 42 obstructive azoospermic men, followed by ICSI procedures with either fresh (n = 40) or frozen-thawed (n = 13) epididymal spermatozoa. Comparing all ICSI cycles with fresh and frozen-thawed epididymal spermatozoa, the fertilization rates (77.4 vs 86.8%) and the cleavage rate (91.3 vs 95.1%) were not statistically different. A total of 64 embryo transfers were performed: 48 embryo transfers after the use of fresh epididymal spermatozoa and 16 embryo transfers after the use of frozen-thawed spermatozoa. The overall pregnancy rate per embryo transfer was also similar between both groups (40.8 vs 40%). The implantation rate per embryo (18.2 vs 12.7%), clinical pregnancy per embryo transfer (36.7 vs 33.3%) and delivery/ongoing pregnancy rate (36.7 vs 33.3%) were not statistically different. In conclusion, there were no significant differences of the outcome of intracytoplasmic sperm injection using fresh and frozen-thawed epididymal spermatozoa obtained by PESA.

Adult↗
PubMed1998

Assisted reproduction for the treatment of azoospermia.

Azoospermia, the most severe form of male infertility, is caused by obstructions in the genital tract or by testicular failure. Microsurgical techniques are available for the correction of some of these obstructions but no effective treatment is available for testicular failure. In recent years, methods have been developed for direct surgical sperm sampling from either the epididymis or the testis to be used by intracytoplasmic sperm injection. The main approach proven to be effective for the retrieval of spermatozoa from the epididymis in patients with obstructive azoospermia is microsurgical epididymal sperm aspiration, although recently the retrieval of spermatozoa by fine needle aspiration was shown to be equally effective. Recovery of spermatozoa is also now performed in patients with severely deficient spermatogenesis using testicular open biopsy as well as aspiration by fine needle. The ultimate choice of sperm retrieval method in these patients will depend not only on sperm availability, but also on the physiological consequences of the different techniques on testicular function. This article summarizes the recent advances achieved in the treatment of azoospermic patients using these assisted reproduction surgical techniques.

Humans↗
PubMed2005

Seminal plasma inhibin-B level is a useful predictor of the success of conventional testicular sperm extraction in patients with non-obstructive azoospermia.

AIM: The value of serum inhibin-B as a predictor of the presence of testicular spermatozoa is still controversial. The purpose of this study is to evaluate the predictive value of the seminal plasma inhibin-B level, which might more directly reflect the secretion by Sertoli cells, and to discriminate between successful and failed testicular sperm extraction (TESE) in non-obstructive azoospermia. METHODS: Sixty-two patients with non-obstructive azoospermia were examined at the Department of Obstetrics and Gynecology at Niigata University Hospital, Niigata, Japan. The level of inhibin-B was measured using a two-site enzyme-linked immunoassay. RESULTS: Testicular sperm were successfully retrieved in 17 of 62 patients (27.4%). The serum levels of follicle-stimulating hormone (FSH) were significantly lower and the serum and seminal inhibin-B concentrations were significantly higher in the successful TESE group compared with the failed TESE group. According to the receiver operating characteristics (ROC) curve analysis, the best discriminating seminal plasma inhibin-B level was 27.0 pg/mL (sensitivity 88.2%, specificity 93.3%). The best discriminating serum inhibin-B level was 34.0 pg/mL (sensitivity 70.6%, specificity 95.6%). The area under the ROC curve for seminal plasma inhibin-B was significantly larger than that for FSH and testicular volume. Using multivariate logistic regression analysis, only seminal plasma inhibin-B was an independent predictor of the presence of spermatozoa on TESE. CONCLUSION: Seminal plasma inhibin-B level is a useful predictor of the presence of testicular sperm in men with non-obstructive azoospermia.

Adult↗
PubMed1999

Clinical application of intracytoplasmic sperm injection using in vitro cultured testicular spermatozoa obtained the day before egg retrieval.

OBJECTIVE: To study the effect of in vitro culture on the quality of human testicular sperm and the efficiency of intracytoplasmic sperm injection with in vitro cultured testicular sperm. DESIGN: Clinical study. SETTING: A private IVF center. PATIENT(S): Twenty consecutively seen IVF patients undergoing testicular biopsies for ICSI. INTERVENTION(S): The testicular specimens were cultured in vitro for 24 hours and the isolated spermatozoa were microinjected. MAIN OUTCOME MEASURE(S): Preincubation and postculture sperm motility, and fertilization, implantation, and pregnancy rates after intracytoplasmic sperm injection. RESULT(S): Motility increased from initial nonmotile or twitching sperm to free motile sperm in 18 of 20 cases. The injection of in vitro cultured testicular sperm resulted in a fertilization rate of 58%, an implantation rate of 20%, and a pregnancy rate of 45%. CONCLUSION(S): A testicular biopsy procedure can be performed the day before egg retrieval. Despite the low initial sperm quality, a high percentage of the prepared testicular sperm showed increased motility after 24 hours of culture. The injection of in vitro cultured testicular sperm into matured oocytes resulted in fertilization, implantation, and pregnancy rates comparable to those obtained with ejaculated sperm.

Adult↗
PubMed2002

Five years experiences with microinjection of testicular spermatozoa into oocytes in Hungary.

The aim of the study was to summarize our five years experience (1996-2000) of testicular spermatozoa for intracytoplasmic sperm injection in Hungary. The influence of sperm count, maternal age, number of transferred embryos, and application of assisted hatching on outcome was investigated. Testicular spermatozoa were retrieved by microsurgical testicular sperm extraction. Samples were classified depending on the number of spermatozoa. Indication for testicular sperm extraction in conjunction with intracytoplasmic sperm injection was severe azoospermia or azoospermia combined with tubal origin infertility. Ovarian stimulation was carried out using an ultrashort protocol with GnRH agonist and gonadotrophin. Intracytoplasmic sperm injection was performed without PVP. Embryos were cultured for 48 or 72 h before embryo transfer. Indications for assisted hatching included elevated maternal age, increased zona thickness or at least two previous unsuccessful IVF cycles. Testicular spermatozoa were successfully retrieved in 218 out of 273 cases. Extreme low sperm count was found more frequently in cases of nonobstructive azoospermia. No significant differences were observed in fertilization rate (61.1% vs. 51.7%) or clinical pregnancy rate (29.0% vs. 26.7%) between patients with obstructive or nonobstructive azoospermia. Maternal age, number of transferred embryos and application of assisted hatching had a significant effect on outcome. A total of 55 clinical pregnancies were achieved, including 14 sets of twins, three sets of triplets and two sets of quadruplets. It is concluded that testicular sperm extraction is an efficient way of obtaining testicular spermatozoa, allowing not only successful fertilization by ICSI, but also freezing of testicular spermatozoa for use in subsequent cycles.

Female↗
PubMed1999

Assisted reproduction technology for patients with congenital bilateral absence of vas deferens.

PURPOSE: We investigate the frequency of cystic fibrosis transmembrane conductance regulator gene mutations in Japanese patients with congenital bilateral absence of the vas deferens, and assess treatment outcomes of assisted reproduction interventions. MATERIALS AND METHODS: In 10 Japanese patients with bilateral congenital absence of the vas deferens genetic analysis was performed for known frequent mutations of the cystic fibrosis transmembrane conductance regulator gene using polymerase chain reaction amplification followed by dot-blot hybridization with the allele-specific oligonucleotide probes and direct sequencing. Intracytoplasmic sperm injection using spermatozoa retrieved from the testes was performed in 7 of the couples. RESULTS: No known mutations of the gene were detected in the patients. However, analysis of the polythymidine tract polymorphism in intron 8 revealed 30% allele frequency of 5T. Pregnancy was achieved in 7 cycles of intracytoplasmic sperm injection using spermatozoa retrieved from the testes. CONCLUSION: The 5T variant in intron 8 polythymidine tract was identified with high allelic frequency in Japanese patients with congenital bilateral absence of the vas deferens, suggesting that the disease in Japan is also partially caused by this particular mutation of the cystic fibrosis transmembrane conductance regulator gene. Modern assisted reproduction technology offers an important option for patients with congenital bilateral absence of the vas deferens.

Adult↗
PubMed2005

Expression and immunolocalization of the calpain-calpastatin system in the human oocyte.

OBJECTIVE: To investigate the expression of the calpain-calpastatin system in the human oocyte. DESIGN: The expression of the calpain-calpastatin system was determined by immunohistochemistry and immunoblot analysis. SETTING: Academic research laboratory. PATIENT(S): Twenty Israeli women who underwent IVF for fertility problems. INTERVENTION(S): Oocytes that had no pronuclei 24 hours after insemination by either conventional IVF or intracytoplasmic sperm injection were retrieved for the study. MAIN OUTCOME MEASURE(S): Analysis of calpain isoforms (m, mu) and calpastatin distribution within the human oocyte. RESULT(S): Western blot analysis confirmed the expression of calpain and calpastatin. Immunohistochemistry of fixed, permeabilized oocytes exhibited localization of both calpains to the cortical region of the oocyte, as well as the cytosol. Calpastatin seemed to be distributed throughout the cytosol, with a marked accumulation in the cell membrane. We have demonstrated a negative correlation between the occurrence of cortical granule exocytosis and the stability of the metaphase plate. CONCLUSION(S): A complete calpain-calpastatin system is expressed in the human oocyte and might play a role in the various calcium-mediated processes occurring during activation of human oocytes.

Blotting, Western↗
PubMed1994

Correlation between epididymal length and fertilization rate in men with congenital absence of the vas deferens.

OBJECTIVE: To investigate whether the variable length of the epididymides in men with congenital absence of the vas deferens might have a correlation with IVF and pregnancy rate results. DESIGN: Microsurgical retrieval of epididymal sperm from men with congenital absence of the vas deferens and their use for IVF. SETTING: Center for Reproductive Health, University of California, Irvine, California. PATIENTS: One hundred eight men with confirmed diagnosis of congenital absence of the vas deferens enrolled in the microsurgical epididymal sperm aspiration and IVF program. INTERVENTIONS: Measurement in centimeters of the epididymal length at the time of the sperm aspiration procedure. MAIN OUTCOME MEASURE: Rates of fertilization and pregnancy according to the epididymal length. RESULTS: Three groups were identified: group I (n = 29), epididymal length between 0.5 and 1.9 cm; group II (n = 66), length between 2.0 and 4.0 cm; and group III (n = 13), length in excess of 4.0 cm. Although the aspiration site was the proximal caput for each case, patients of group III had the highest fertilization and pregnancy rate (24% and 43%, respectively). Patients with the shortest epididymis (group I) had the worst IVF outcome (fertilization rate 7% and pregnancy rate 7%) whereas in group II the fertilization rate was 13% and the pregnancy rate was 18%. CONCLUSION: This study demonstrates that epididymal sperm from men with congenital absence of the vas deferens having a longer epididymis have a better IVF rate. A long epididymis can allow [1] the arrival of more frequent waves of fresh sperm whereas in a short epididymis the system is completely congested and occupied by old and senescent sperm, [2] less obstructive damages, and [3] a back flow of biochemical factors produced in the more distal segments that could ultimately enhance the fertilization capacity of proximal epididymal sperm.

Epididymis↗
PubMed2005

Polar body morphology and spindle imaging as predictors of oocyte quality.

It has been suggested that first polar body (PBI) morphology reflects oocyte competence. Oocytes with an intact normal-sized PBI have been described as generating better day 2 embryos, higher blastocyst yield, and increased pregnancy and implantation rates. In other studies, PBI morphology was found to be unrelated to fertilization rate, embryo quality, and blastocyst formation. In a prospective analysis, the predictive value of the PBI was investigated by comparing the development of oocytes retrieved from intracytoplasmic sperm injection patients and displaying different PBI morphology, classified according to the following characteristics: normal size and smooth surface (I), fragmented (II), rough surface (III), or large size (IV). Fertilization rates were 59, 57, 64 and 60% respectively. No significant differences were found between the various groups. The proportions of high quality (grade A) day 2 embryos were also comparable among groups I-III (14, 12 and 17% respectively), while the low number of grade A embryos in group IV (two embryos) did not allow comparison with the other classes. These data do not suggest that PBI selection can contribute to identification of embryos with high developmental ability. In order to establish alternative criteria for oocyte selection, a metaphase II (MII) spindle analysis was also conducted via Polscope. In oocytes of patients of different age, spindle retardance (which reflects the high order and density of microtubules) was compared with parameters of embryo development. In aged patients, a trend was observed between low retardance and poor embryo quality, although in general the association between retardance and oocyte developmental performance did not reach statistical significance.

Adult↗
PubMed2001

The extended role of the nurse--opportunity or threat?

Nursing practice is undergoing changes that are both exciting and controversial. The UKCC Scope of Professional Practice has encouraged nurses to re-evaluate their practice and, as a result, nurses from various fields have expanded their roles to meet the changing needs of patients and the profession. Published evidence shows that nurses can be as effective as doctors within these expanded roles, but that there is a danger that gender issues will cloud the debate because of the assumption that all nurses are female and all doctors are male. This problem is especially evident when female nurses perform an extended role involving male patients, although female doctors are in a similar position and work with the same patients without undue comment. The roles of doctors and nurses should complement each other, and all practitioners should work for the benefit of patients in their care, rather than defending traditional roles and hierarchy. There is confusion surrounding accountability of nurses who work in an extended role between the medical and the nursing profession, and both the Royal College of Nursing and the British Medical Association need to clarify the situation. This article looks at the arguments for and against the extended role of the nurse specialist and discusses current opinions within the nursing and medical fields. The article also describes how nurses at Midland Fertility Services have successfully extended their role to encompass ultra-sound-guided oocyte retrieval and surgical sperm recovery.

Education, Nursing↗
PubMed1995

Natural cycles for in-vitro fertilization: cost-effectiveness analysis and factors influencing outcome.

Improvements in oocyte culture technique, sperm preparation, oocyte retrieval method and ovarian stimulation regimens have produced higher pregnancy rates with in-vitro fertilization (IVF) treatment. However, because ovarian stimulation is expensive and not without risk, there is increasing interest in the option of using natural cycles for IVF. This study was performed to document the experience and outcome in 240 natural cycles. Cancellation occurred in 28 cycles (12%), and LH surge was observed in 56 (23%), leaving 156 (65%) cycles which progressed to oocyte retrieval. No oocytes were retrieved in 26 cycles. Among the successful oocyte retrievals, the majority yielded one oocyte. There was no evidence of fertilization in 26 cases, and triploid fertilization was observed in 12 cases. Embryos suitable for transfer were available in 92 cycles in which 11 (12%) clinical pregnancies were confirmed. Despite the high failure rate at each step in the process, natural cycles are more cost-effective than stimulated cycles which incur an incremental cost per live birth of $48,000. Natural cycles offer a low-cost alternative that may be more accessible to patients.

Adult↗