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PubMed1995

Improvement of sperm motility by the addition of progesterone to the Percoll medium during sperm purification.

The Percoll centrifugation technique is widely used to select the most motile spermatozoa in connection with assisted reproduction techniques (ART). Progesterone is known to enhance the motility of spermatozoa in vivo and in vitro. This study evaluates whether the motility of spermatozoa can be enhanced by the presence of progesterone simultaneously with purification using a routine Percoll centrifugation technique. Motility is measured by computer-assisted sperm analysis. The 100% Percoll medium contained a progesterone concentration of 2 micrograms/ml, which is in the range of that found in pre-ovulatory follicular fluid and peritoneal fluid around ovulation. With a two-layer purification procedure (55/80% Percoll medium), exposure of the progesterone in the Percoll medium for only 25 min caused a highly significant improvement of motility in the spermatozoa isolated from the semen samples of 14 healthy men. It is concluded that the addition of progesterone to the Percoll purification medium can further enhance sperm motility without the need for a change in the routinely used semen purification technique in most assisted reproduction programmes.

Cell Separation↗

PubMed2005

[Clinical features & diagnostic and therapeutic strategies of congenital absence of the vas deferens].

OBJECTIVE: To investigate the clinical characteristics, diagnosis and therapeutic strategies of congenital absence of the vas deferens (CAVD). METHODS: We summarized the clinical data of 81 cases of CAVD and investigated clinical features, diagnosis and management of the disease. RESULTS: Seventy-nine cases of infertility were diagnosed as CAVD at the clinic, and 2 were diagnosed during surgical exploration. The population consisted of 40 cases of congenital bilateral absence of the vas deferens (CBAVD), 25 cases of congenital unilateral absence of the vas deferens (CUAVD), and 16 cases of segmental agenesis of the vas deferens. Seventy-four spouses received the treatment of assisted reproductive techniques, including intracytoplasmic sperm injection (ICSI) in 12 cases, and 4 of them achieved pregnancy. CONCLUSION: CAVD frequently presents with infertility. CBAVD may manifest as obstructive azoospermia, and CUAVD and segmental vasal agenesis as oligospermia, asthenospermia, or obstructive azoospermia. CAVD is usually not difficult to diagnose, but may be missed due to careless examination. Assisted reproductive technology (ART) plays a key role in the management of CAVD.

Adult↗

PubMed2001

The effects of assisted reproduction on the trends and zygosity of multiple births in England and Wales 1974-99.

Assisted reproductive techniques have led to an increase in the proportion of maternities that are multiple. Though predominantly dizygotic, they are at greater risk of monozygotic division than those spontaneously conceived. England and Wales data 1974-99 on stillbirths and livebirths were analysed for 4 periods: 1974-80 (pre-assisted reproduction; 1982-8; 1989-91 (pre-redefinition of stillbirth); 1993-9 (post-redefinition of stillbirth). For twin data, Weinberg's rule was applied to estimate the proportions that were mono- (MZ) and dizygotic (DZ). Compared with the period before assisted reproduction, the most recent period shows an increase in twin maternities of 3.81 per 1,000 comprised of 3.22 (95% CI 3.10 to 3.33; p < 0.0001) DZ and 0.60 (95% CI 0.51 to 0.68; p < 0.0001) MZ twins. It is estimated that 15.7% of assisted reproduction twins are MZ. Higher order multiple births showed an increase of 3.06 (95% CI 2.85 to 3.29; p < 0.0001) per 10,000 maternities. Stillbirth rates in MZ twins are of the same order of magnitude as those in higher order multiple births but higher than those in DZ twins. The improvement in stillbirth rates over the 26 year study period is of the same order magnitude in singletons, DZ and MZ twins and higher order multiples. Assisted reproduction has led to a significant increase in the proportion of MZ twins. These are at high risk of fetal death and this needs to be considered when local stillbirth and perinatal mortality rates are used in auditing obstetric services.

England↗

PubMed2004

Fertility after cancer: a prospective review of assisted reproductive outcome with banked semen specimens.

OBJECTIVE: To examine the outcome of assisted reproduction techniques (ART) using cryopreserved semen from patients with cancer. DESIGN: Prospective. SETTING: Therapeutic semen banking program at a tertiary healthcare center. PATIENT(S): Twenty-nine men with cancer who cryopreserved their sperm before treatment at our facility from 1982 to 2001 and withdrew their samples for assisted reproduction (IUI, IVF, or intracytoplasmic sperm injection [ICSI]). INTERVENTION(S): Sperm bank records were used to identify the patients. Information on fertility potential indices was obtained from medical records and through interviews. Of the 29 patients, 9 had testicular cancer, 12 had Hodgkin's disease, and 8 had other types of cancer. MAIN OUTCOME MEASURE(S): Pregnancy and live births. RESULT(S): A total of 87 ART cycles (42 IUI, 26 IVF, and 19 ICSI) was performed. Of those cycles, 18.3% resulted in pregnancy (7% IUI, 23% IVF, and 37% ICSI), and 75% of the pregnancies resulted in a live birth (100% IUI, 83% IVF, and 57% ICSI). There was no significant difference in the outcomes when the results were stratified by type of ART and malignancy. None of the 11 infants who were born had congenital anomalies. CONCLUSION(S): Our findings emphasize the need for physicians to discuss the issue of semen cryopreservation with all men of reproductive age who have cancer before antineoplastic therapy is started.

Antineoplastic Agents↗

PubMedDate not supplied

Cryopreservation of spermatozoa: a 1996 review.

Both the ability to freeze human spermatozoa and the possibility of pregnancy following intrauterine insemination have existed for >40 years. There have been a number of improvements during that time concerning the methods of freezing and thawing human spermatozoa. Initially, the use of the cryoprotective properties of glycerol allowed a major improvement; subsequently, changes were mainly empirical. It was a long time before specific cryobiological studies were undertaken. However, the necessity for these became apparent with the partial recovery or sometimes loss of motility after freezing either subfertile semen before chemotherapy or radiotherapy, or spermatozoa collected from non-physiological situations (epididymal or testicular spermatozoa). The main trends in improvement have defined end-points other than the percentage of motility recovery or the assessment of ultrastructural damage. More sensitive criteria of the objective assessment of motility, energy status, damage to the plasma membrane or to subcellular elements, chromatin stability and chromosomal damage have been proposed as complementary end-points to better assess sperm cryopreservation. A different approach was related to the biochemical environment and physical conditions imposed on spermatozoa during the freezing and thawing process. Biochemical changes were assessed following different combinations of various extenders which attempted either to better preserve some parameter or to avoid the tendency towards drastic increase in osmotic pressure. Analysis of physical conditions was linked to the rate of cooling, freezing and warming, and was based on cryobiological studies. Finally, even though such improvements are not negligible, many questions remain unanswered. The extensive use of frozen spermatozoa during assisted reproductive techniques, together with the development of assisted fertilization using surgically collected spermatozoa, creates the need for additional studies to improve the cryopreservation of human spermatozoa.

Cryopreservation↗

PubMed2004

What is the most relevant standard of success in assisted reproduction? Singleton live births should also include preterm births.

An intensive debate is ongoing in this journal concerning the most appropriate endpoint after assisted reproduction techniques. The endpoint suggested by the first authors was Birth Emphasizing a Successful Singleton at Term (BESST). We have evaluated the most appropriate endpoint from different perspectives: patients, public, health authorities, obstetric and IVF clinics. We find singleton live birth highly relevant as an outcome parameter as multiple pregnancies are the main factor responsible for the overall poorer obstetric and neonatal outcome in IVF pregnancies, and multiple pregnancies are mostly an avoidable iatrogenic complication. However, our proposal is that both preterm and term singletons should be included since the prematurity rate is an outcome that is largely uninfluenced by the IVF clinics. In conclusion, we propose singleton live birth per cycle initiated as the most appropriate main outcome after assisted reproduction. Prematurity should in addition be reported separately as a secondary outcome.

Congenital Abnormalities↗

PubMed2004

The effect of sperm DNA damage on assisted reproduction outcomes. A review.

The quality of sperm DNA is very important in maintaining the reproductive potential of men. Sperm DNA is resistant to many types of insults that occur during its journey from the testis to time it reaches the oocyte for fertilization. During natural conception, a selection process occurs that allows only sperm with intact DNA to fertilize an oocyte. When assisted reproductive techniques (ART) are used, some or all of this selection process is bypassed. As a result, sperm with damaged DNA may fertilize an oocyte. Damage to sperm nuclear DNA negatively affects assisted and natural fertility. Increasingly, sperm DNA is being recognized as an independent measure of sperm quality that may have better diagnostic and prognostic capabilities than standard sperm parameters. This review summarizes the available evidence for the role of sperm DNA damage in assisted fertility. Two important facts are obvious from the available evidence: 1) men with spermatozoal DNA damage appears to have a decreased ability to father offspring, 2) spermatozoa with abnormal DNA can fertilize an oocyte, which may progress to a live birth. Infertile men who are planning to undergo ART procedures with their partner should have their sperm evaluated for DNA damage. The results of this evaluation may be used to counsel the couple about their chances for live birth and for genomic abnormalities in their offspring.

DNA Damage↗

PubMed2004

Sperm DNA damage and its clinical relevance in assessing reproductive outcome.

The routine examination of semen, which assesses sperm concentration, percentage motility and morphology, does not identify subtle defects in sperm chromatin architecture. The focus on the genomic integrity of the male gamete has intensified recently due to the growing concern that genetic diseases may be transmitted via assisted reproductive techniques (ART). Accordingly, the intent of this review is to describe the details of the information pertaining to mitochondrial/nuclear sperm DNA damage with an emphasis on its clinical significance and its relationship with male infertility. Assessment of sperm DNA damage appears to be a potential tool for evaluating semen samples prior to their use in ART. Testing DNA integrity may help select spermatozoa with intact DNA or with the least amount of DNA damage for use in assisted conception. In turn, this may alleviate the financial, social and emotional problems associated with failed ART attempts.

Adult↗

PubMed2006

Exploiting LH in ovarian stimulation.

During intermediate-late phases of human folliculogenesis, LH plays a key role in promoting steroidogenesis and growth of the leading follicle. Ovarian stimulation for assisted reproduction techniques usually consists of administering exogenous FSH in a low LH environment. Although an impairment in LH-dependent paracrine activities would be expected, multiple follicular growth is efficiently achieved in almost all patients. Thus, there appears to be a discrepancy between classical folliculogenesis models and data from IVF. This study examines the 'interface' between basic endocrinological and clinical evidence, in an attempt to answer two questions: is there an LH therapeutic window, and if there is, how can this be exploited in the practice of assisted reproduction? It also reviews the evidence that specific subgroups of women may benefit from LH supplementation during ovarian stimulation.

Adult↗

PubMed1998

Lower risks of adverse outcome in twins conceived by artificial reproductive techniques compared with spontaneously conceived twins.

The outcomes of twins conceived by 136 women after medical assistance (MA) such as ovulation induction with or without assisted reproductive techniques, and twins conceived spontaneously (SP) by 72 women were compared. All 208 women were monitored from < 20 weeks gestation; they all delivered at > or = 24 weeks gestation. The chorionicity of the placenta was diagnosed antenatally and confirmed after delivery. There were 10 perinatal deaths; the physical and neurological status of the remaining 406 infants was assessed at 1 year of corrected age. There were no differences in gestational age at birth, the birth weights of the larger and smaller twins, the birth weight discordance, or the incidence of life-threatening major malformations between groups. Adverse infant outcomes, such as death, cerebral palsy and mental retardation occurred in nine (3.3%) of 272 MA twins compared with 12 (8.3%) of 144 SP twins (P < 0.05). The placenta was monochorionic in only three (2.2%) of 136 MA twin pregnancies compared with 41 (57%) of 72 SP twin pregnancies (P < 0.001). Of the 21 infants with adverse outcomes, nine had monochorionic placentas. Thus, the risk of an adverse outcome was 2.8-fold higher (95% confidence interval (CI) 1.2-6.4) in monochorionic twins than in dichorionic twins (10 versus 3.7%; P < 0.05). There was no difference in the incidence of adverse infant outcomes between SP (4.8%) and MA (3.4%) twins with dichorionic placentas. These findings suggest that ovulation induction in itself was not associated with an adverse outcome of twin pregnancies. The lower frequency of monochorionic placentas in MA twins may have been responsible for the lower risk of an adverse outcome in MA twins.

Birth Weight↗

PubMed2004

Assisted reproduction in the treatment of polycystic ovarian syndrome.

Treatment of patients with polycystic ovary syndrome (PCOS) with assisted reproductive techniques is a great challenge for the infertility specialist. Patients with PCOS demonstrate many problems, such as excessive body weight and hyperinsulinaemia, that render management more complex. Prior to treatment with IVF, the PCOS patient should be thoroughly evaluated for disclosure of endometrial neoplasia, hyperinsulinaemia, and other general health related problems. Ovarian stimulation for IVF carries the risks of overstimulation and severe hyperstimulation, which should be avoidable in most cases with preventive measures. The outcome in terms of pregnancy and implantation rates is similar for patients with PCOS when compared with patients undergoing IVF for other indications. There are some questions regarding oocyte and embryo quality in women with PCOS. This manifests itself in lower fertilization rate and decreased embryo quality in some studies. However, increased numbers of oocytes available for insemination or ICSI compensate for decreased fertilization rates and embryo quality. More recent studies suggest higher cumulative conception rates in women with PCOS when compared with controls. In-vitro maturation (IVM) of oocytes retrieved from non-stimulated or minimally stimulated cycles represents a viable option that should be considered seriously when assisted conception is attempted. Results of IVM, however, should be improved further and generalized before the technique can be advocated as the initial treatment approach in these patients.

Cellular Senescence↗

PubMed1992

Male factor infertility and assisted reproductive technologies.

Male infertility has many facets that need to be evaluated in an initial screening. Once these are known, recommendations become clearer for aggressively pursuing assisted reproductive techniques. Progress has been made in defining more clearly the severe male factor: concentration less than 5 x 10(6) sperm/mL, motility less than 10%, morphology less than 4% normal forms (by strict criteria), and recovered swim-up sperm less than 1.5 x 10(6). Sperm preparation techniques may be improved by use of Percoll separation medium, and morphology may be used in prediction of cleavage rate in in vitro fertilization. Hopefully, these techniques will lead to more specific guidelines for successful use of assisted reproductive technology in male factor patients.

Female↗

PubMed2005

Perinatal outcome of 12,021 singleton and 3108 twin births after non-IVF-assisted reproduction: a cohort study.

Perinatal outcome of pregnancies caused by assisted reproduction technique (ART) is substantially worse when compared with pregnancies following natural conception. We investigated the possible risks of non-IVF ART on perinatal health. We conducted a retrospective cohort study with two exposure groups: a study group of pregnancies after controlled ovarian stimulation (COS), with or without artificial insemination (AI), and a naturally conceived comparison group. We used the data from the regional registry of all hospital deliveries in the Dutch-speaking part of Belgium during the period from January 1993 until December 2003 to investigate differences in perinatal outcome of singleton and twin pregnancies. 12 021 singleton and 3108 twin births could be selected. Naturally conceived subjects were matched for maternal age, parity, fetal sex and year of birth. The main outcome measures were duration of pregnancy, birth weight, perinatal morbidity and perinatal mortality. Our overall results showed a significantly higher incidence of prematurity (<32 and <37 weeks), low and very low birth weight, transfer to the neonatal intensive care unit and most neonatal morbidity parameters for COS/AI singletons. Twin pregnancies resulting from COS/AI showed an increased rate of neonatal mortality, assisted ventilation and respiratory distress syndrome. After excluding same-sex twin sets, COS/AI twin pregnancies were at increased risk for extreme prematurity and very low birth weight. In conclusion, COS/AI singleton and twin pregnancies are significantly disadvantaged compared to naturally conceived children.

Adult↗

PubMed1996

The effect of various ovulation induction protocols on pregnancy rates following intracytoplasmic sperm injection.

In the last two years intracytoplasmic sperm injection (ICSI) has become frequently employed as an assisted reproductive technique primarily to treat male factor infertility.' In order to achieve high pregnancy rates, all assisted reproductive technologies including ICSI require sufficient number and quality oocytes. In our practice we use three different ovulation induction regimens (CC/hMG, GnRH-a/hMG, and GnRH-a/FSH) to maximize the number of oocytes available for fertilization. In this present report, we retrospectively com- pared pregnancy rates with ICSI following the use of these protocols.

Journal Article↗

PubMed2005

Influence of global sperm DNA methylation on IVF results.

BACKGROUND: In cases of male infertility, routine analysis for sperm characteristics is a poor predictive factor for the segmentation rate and embryo development in assisted reproductive technologies. It is assumed that epigenetic factors could have an influence on the embryo's quality. The aim of this work was to determine the relationship between sperm DNA methylation level and fertilization and pregnancy rates according to the assisted reproduction technique performed. METHODS: A prospective study was undertaken. Ejaculates were obtained from men (n = 63) undergoing an assisted reproduction procedure. 5-Methylcytosine was immunostained with a polyclonal antibody and revealed by fluorescein isothiocyanate. The DNA methylation level was then quantified by flow cytometry. RESULTS: Sixty-three conventional IVF cycles were performed, 760 oocytes were retrieved, an average of 8.1 +/- 4.8 embryos was obtained, and 2.4 embryos were transferred. Neither the fertilization rate nor the rate of good quality embryos was correlated with the DNA methylation level (r = -0.1 and r = -0.08 respectively; not significant). When sperm DNA methylation was >555 arbitrary units, the pregnancy rate was 33.3% compared with 8.3% in the lower (<555) group (P<0.05). CONCLUSION: DNA methylation level in human sperm could represent a new approach to study the ability of sperm to lead to pregnancy in an assisted reproduction procedure, especially when sperm samples with normal characteristics are used.

5-Methylcytosine↗

PubMedDate not supplied

Apoptosis in human ejaculated spermatozoa.

After the introduction of assays determining apoptosis in human ejaculated spermatozoa, several studies have been published about the relationship between apoptosis in spermatozoa and semen quality. Apoptosis in spermatozoa is significantly correlated with conventional semen quality parameters, but also with the outcome of assisted reproductive techniques. The apoptotic process is probably set in motion before ejaculation. Determining apoptosis in spermatozoa can improve selection criteria in assisted reproduction.

Annexin A5↗

PubMed1999

The current status of equine embryo transfer.

The use of embryo transfer in the horse has increased steadily over the past two decades. However, several unique biological features as well as technical problems have limited its widespread use in the horse as compared with that in the cattle industry. Factors that affect embryo recovery include the day of recovery, number of ovulations, age of the donor and the quality of sire's semen. Generally, embryo recoveries are performed 7 or 8 d after ovulation unless the embryos are to be frozen, in which case recovery is performed 6 d after ovulation. Most embryos are recovered from single-ovulating mares. Because there is no commercially available hormonal preparation for inducing multiple ovulation in the horse, equine pituitary extract has been used to increase the number of ovulations in treated mares, but FSH of ovine or porcine origin is relatively ineffective in inducing multiple ovulation in the mare. Factors shown to affect pregnancy rates after embryo transfer include method of transfer, synchrony of the donor and recipient, embryo quality, and management of the recipient. One of the major improvements in equine embryo transfer over the last several years is the ability to store embryos at 5 degrees C and thus ship them to a centralized station for transfer into recipient mares. Embryos are collected by practitioners on the farm, cooled to 5 degrees C in a passive cooling unit and shipped to an embryo transfer station without a major decrease in fertility. However, progress in developing techniques for freezing equine embryos has been slow. Currently, only small, Day-6 equine embryos can be frozen with reasonable success. Additional studies are needed to refine the techniques for freezing embryos collected from mares 7 or 8 d after ovulation. Demand for the development of assisted reproductive techniques in the horse has increased dramatically. Collection of equine oocytes by transvaginal, ultrasound-guided puncture and the transfer of these oocytes into recipients is now being used to produce pregnancies from donors that had previously been unable to provide embryos. In vitro fertilization, however, has been essentially unsuccessful in the horse. One alternative to in vitro fertilization that has shown promise is intracytoplasmic sperm injection. However, culture conditions for in vitro-produced embryos appear to be inadequate. The continued demand for assisted reproductive technology will likely result in the further development of techniques that are suitable for use in the horse.

Animals↗

PubMed2005

[Laser assisted intracytoplasmic sperm injection: a more effective and faster technique of immobilization of spermatozoa than traditional one].

AIM: Intracytoplasmic sperm injection (ICSI) is employed routinely in the assisted reproductive technique, in particular in case of male factor infertility. Recently, some options have been introduced in the micromanipulation system employed in ICSI, improving the performance of this technique. One of these is a no-contact laser, mostly used for the assisted hatching and the blastomere biopsy in preimplantation genetic diagnosis. One of the most important step of the ICSI technique is the sperm immobilization. Normally, this is performed by the operator and needs some time. METHODS: A one-year perspective-comparative study has been carried out and the results obtained with the traditional technique of immobilization of spermatozoa have been compared with those obtained with the laser technique (spermatozoa previously immobilized by no-contact laser). We have evaluated 3 parameters: 1) fertilization rate; 2) cleavage rate and 3) time needed to immobilize sperm. RESULTS: Some interesting findings have been observed: the embryo quality, fertilization rate and cleavage rate seem the same in both groups. The most interesting finding is the drastic reduction of the time needed for microinjection when the laser technique is used. CONCLUSIONS: This technique will reduce the total time needed to perform the ICSI, decreasing the time of exposure of the gametes outside the incubator and reducing the possibility of irreversible damage.

Adult↗