Preimplantation genetic diagnosis for advanced maternal age and other indications

Diminished Ovarian Reserve Chemotherapy-Induced Mouse Model: A Tool for the Preclinical Assessment of New Therapies for Ovarian Damage

Diminished ovarian reserve (DOR) and primary ovarian insufficiency (POI) are primary factors leading to infertility. However, there is a lack of appropriate animal models of DOR usable for assessing new therapeutic strategies. In this study, we aimed to evaluate whether chemotherapy treatment in mice could reproduce features similar of that observed in women with DOR. Twenty-one Nonobese diabetic/severe combined immunodeficiency (NOD/SCID) female mice were allocated to 3 groups (n = 7/group): control, single dose of vehicle (Dimethyl Sulfoxide [DMSO]); DOR, single reduced chemotherapy dose; and POI, single standard chemotherapy dose. After 21 days, mice underwent ovarian hyperstimulation and mating. Part of the animals were harvested to analyze ovarian reserve, ovulation and fertilization rates, and morphology, apoptosis, and vascularization of the ovarian stroma. The remaining mice underwent multiple matings to assess pregnancy rates and litter sizes. The DOR and POI mice showed an impaired estrous cyclicity and a decrease in ovarian mass, number of follicles, Metaphase II (MII) oocytes, and embryos as well as in ovarian stroma vascularization. Mice in both models showed also an increase in the percentage of morphologically abnormal follicles, stromal degeneration, and apoptosis. Similar to that observed in DOR and POI patients, these impairments were less severe in DOR than in POI mice. None of the POI females were able to achieve a pregnancy. Meanwhile, DOR females achieved several consecutive pregnancies, although litter size was decreased when compared to controls. In conclusion, a mouse model which displayed most of the ovarian characteristics and fertility outcomes of women with DOR has been established using a single dose of chemotherapy.

Impact of Ovarian Aging in Reproduction: From Telomeres and Mice Models to Ovarian Rejuvenation

The trend in our society to delay procreation increases the difficulty to conceive spontaneously. Thus, there is a growing need to use assisted reproduction technologies (ART) to form a family. With advanced maternal age, ovaries not only produce a lower number of oocytes after ovarian stimulation but also a lower quality-mainly aneuploidies-requiring further complex analysis to avoid complications during implantation and pregnancy. Although there are different options to have a child at advanced maternal age (like donor eggs), this is not the preferred choice for most patients. Unless women had cryopreserved their eggs at a younger age, reproductive medicine should try to optimize their opportunities to become pregnant with their own oocytes, when chances of success are reasonable. Aging has many causes, but telomere attrition is ultimately one of the main pathways involved in this process. Several reports link telomere biology and reproduction, but the molecular reasons for the rapid loss of ovarian function at middle age are still elusive. This review will focus on the knowledge acquired during the last years about ovarian aging and disease, both in mouse models of reproductive senescence and in humans with ovarian failure, and the implication of telomeres in this process. In addition, the review will discuss recent results on ovarian rejuvenation, achieved with stem cell therapies that are currently under study, or ovarian reactivation by tissue fragmentation and the attempts to generate oocytes in vitro.

Male factor infertility impacts the rate of mosaic blastocysts in cycles of preimplantation genetic testing for aneuploidy

PURPOSE

In this study, we tested the hypothesis that, in PGT-A cycles, decreased semen quality is associated with increased rates of mosaic blastocysts.

METHODS

In a retrospective analysis, three hundred and forty PGT-A cycles are divided into study groups according to semen quality. Cycles were initially divided into two groups, discerning couples with absence of male factor of infertility (non-male factor: NMF; N = 146 cycles) from couples with a male factor of infertility (MF; N = 173 cycles). Couples with severe male factor (SMF) infertility (n = 22) were assessed separately. Embryos were cultured to the blastocyst stage and chromosomally assessed by array comparative genomic hybridization (aCGH). The study did not involve specific interventions.

RESULTS

The reproductive outcome of MF and NMF groups did not indicate statistically significant differences. However, while no differences were found between MF and NMF groups in terms of euploid or aneuploid blastocysts rates, a significantly higher rate of mosaic blastocysts was observed in the MF group (3.6% vs. 0.5%, respectively; P = 0.03). A similar pattern of results was observed in the SMF group when compared with those of the other PGT-A cycles taken together (no SMF). In particular, a significantly higher rate of mosaic blastocysts was observed in the SMF group (7.7% and 1.8%, respectively; P = 0.008).

CONCLUSIONS

The study outcome strongly suggests that compromised semen quality is associated with increased rates of mosaic blastocysts analysed in PGT-A cycles. Sperm assessment appears therefore as an important factor in the determination of embryo development and for a more precise prognostic assessment of PGT-A cases.

Diminished Ovarian Reserve Chemotherapy-Induced Mouse Model: A Tool for the Preclinical Assessment of New Therapies for Ovarian Damage

Diminished ovarian reserve (DOR) and primary ovarian insufficiency (POI) are primary factors leading to infertility. However, there is a lack of appropriate animal models of DOR usable for assessing new therapeutic strategies. In this study, we aimed to evaluate whether chemotherapy treatment in mice could reproduce features similar of that observed in women with DOR. Twenty-one Nonobese diabetic/severe combined immunodeficiency (NOD/SCID) female mice were allocated to 3 groups (n = 7/group): control, single dose of vehicle (Dimethyl Sulfoxide [DMSO]); DOR, single reduced chemotherapy dose; and POI, single standard chemotherapy dose. After 21 days, mice underwent ovarian hyperstimulation and mating. Part of the animals were harvested to analyze ovarian reserve, ovulation and fertilization rates, and morphology, apoptosis, and vascularization of the ovarian stroma. The remaining mice underwent multiple matings to assess pregnancy rates and litter sizes. The DOR and POI mice showed an impaired estrous cyclicity and a decrease in ovarian mass, number of follicles, Metaphase II (MII) oocytes, and embryos as well as in ovarian stroma vascularization. Mice in both models showed also an increase in the percentage of morphologically abnormal follicles, stromal degeneration, and apoptosis. Similar to that observed in DOR and POI patients, these impairments were less severe in DOR than in POI mice. None of the POI females were able to achieve a pregnancy. Meanwhile, DOR females achieved several consecutive pregnancies, although litter size was decreased when compared to controls. In conclusion, a mouse model which displayed most of the ovarian characteristics and fertility outcomes of women with DOR has been established using a single dose of chemotherapy.

Mitochondria as a tool for oocyte rejuvenation

Ovarian aging leads to a decrease in the quantity and quality of oocytes. Aged oocytes have significantly reduced amounts of mitochondria, the energy factories of cells, leading to lower fertilization rates and poor embryonic development. Various techniques have tried to use heterologous or autologous sources of mitochondria to reestablish oocyte health by providing more energy. However, heterologous sources are no longer used owing to the known risk of heteroplasmy. Although autologous methods have recently been tested in humans, they have not shown a clear improvement in embryo quality. In this review, we describe the techniques that have been tested in recent years to provide a state of the art on oocyte rejuvenation through extra injection of mitochondria.

Autologous stem cell ovarian transplantation to increase reproductive potential in patients who are poor responders

OBJECTIVE

To evaluate effects of autologous stem cell ovarian transplant (ASCOT) on ovarian reserve and IVF outcomes of women who are poor responders with very poor prognosis.

DESIGN

Prospective observational pilot study.

SETTING

University hospital.

PATIENT(S)

Seventeen women who are poor responders.

INTERVENTION(S)

Ovarian infusion of bone marrow-derived stem cells.

MAIN OUTCOME MEASURE(S)

Serum antimüllerian hormone levels and antral follicular count (AFC), punctured follicles, and oocytes retrieved after stimulation (controlled ovarian stimulation) were measred. Apheresis was analyzed for growth factor concentrations.

RESULT(S)

The ASCOT resulted in a significant improvement in AFC 2 weeks after treatment. With an increase in AFC of three or more follicles and/or two consecutive increases in antimüllerian hormone levels as success criteria, ovarian function improved in 81.3% of women. These positive effects were associated with the presence of fibroblast growth factor-2 and thrombospondin. During controlled ovarian stimulation, ASCOT increased the number of stimulable antral follicles and oocytes, but the embryo euploidy rate was low (16.1%). Five pregnancies were achieved: two after ET, three by natural conception.

CONCLUSION(S)

Our results suggest that ASCOT optimized the mobilization and growth of existing follicles, possibly related to fibroblast growth factor-2 and thrombospondin-1 within apheresis. The ASCOT improved follicle and oocyte quantity enabling pregnancy in women who are poor responders previously limited to oocyte donation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02240342.

Predictors of live birth and pregnancy success after in vitro fertilization in infertile women aged 40 and over

Objective

The aim of this study was to evaluate pregnancy outcomes and the live birth rate at 1-year age increments in women aged ≥40 years undergoing fresh non-donor in vitro fertilization (IVF) and embryo transfer (ET), and to identify predictors of success in these patients.

Methods

This retrospective study was performed among women ≥40 years of age between 2004 and 2011. Of the 2,362 cycles that were conducted, ET was performed in 1,532 (73.1%).

Results

The clinical pregnancy rate and live birth rate in women ≥40 years significantly decreased with each year of increased age (p<0.001). Maternal age (odds ratio [OR], 0.644; 95% confidence interval [CI], 0.540–0.769; p<0.001), basal follicle-stimulating hormone (FSH) levels (OR, 0.950; 95% CI, 0.903–0.999; p=0.047), the number of high-quality embryos (OR, 1.258; 95% CI, 1.005 –1.575; p=0.045), and the number of transferred embryos (OR, 1.291; 95% CI, 1.064 –1.566; p=0.009) were significant predictors of live birth. A statistically significant increase in live birth rates was seen when ≥3 embryos were transferred in patients 40 to 41 years of age, whereas poor pregnancy outcomes were seen in patients ≥43 years of age, regardless of the number of transferred embryos. Moreover, the cumulative live birth rate increased in patients 40 to 42 years of age with repeated IVF cycles, but the follicle-stimulating hormone in those ≥43 years of age rarely showed an increase.

Conclusion

IVF-ET has acceptable outcomes in those <43 years of age when a patient's own oocytes are used. Maternal age, basal FSH levels, and the number of high-quality embryos and transferred embryos are useful predictors of live birth.

A simple, less invasive stripper micropipetter-based technique for day 3 embryo biopsy

BACKGROUND

Preimplantation genetic screening (PGS) is an important procedure for in vitro fertilization (IVF). A key step of PGS, blastomere removal, is abundant with many technical issues. The aim of this study was to compare a more simple procedure based on the Stipper Micropipetter, named S-biopsy, to the conventional aspiration method.

METHODS

On Day 3, 368 high-quality embryos (>7 cells on Day3 with <10% fragmentation) were collected from 38 women. For each patient, their embryos were equally separated between the conventional method (n = 188) and S-biopsy method (n = 180). The conventional method was performed using a standardized protocol. For the S-biopsy method, a laser was used to remove a significantly smaller portion of the zona pellucida. Afterwards, the complete embryo was aspirated with a Stripper Micropipetter, forcing the removal of the blastomere. Selected blastomeres went to PGS using CGH microarrays. Embryo integrity and blastocyst formation were assessed on Day 5. Differences between groups were assessed by either the Mann-Whitney test or Fisher Exact test.

RESULTS

Both methods resulted in the removal of only one blastomere. The S-biopsy and the conventional method did not differ in terms of affecting embryo integrity (95.0% vs. 95.7%) or blastocyst formation (72.7% vs. 70.7%). PGS analysis indicated that aneuploidy rate were similar between the two methods (63.1% vs. 65.2%). However, the time required to perform the S-biopsy method (179.2 ± 17.5 s) was significantly shorter (5-fold) than the conventional method.

CONCLUSION

The S-biopsy method is comparable to the conventional method that is used to remove a blastomere for PGS, but requires less time. Furthermore, due to the simplicity of the S-biopsy technique, this method is more ideal for IVF laboratories.

The origin, mechanisms, incidence and clinical consequences of chromosomal mosaicism in humans

BACKGROUND

Chromosomal mosaicism, the presence of two or more distinct cell lines, is prevalent throughout human pre- and post-implantation development and can lead to genetic abnormalities, miscarriages, stillbirths or live births. Due to the prevalence and significance of mosaicism in the human species, it is important to understand the origins, mechanisms and incidence of mosaicism throughout development.

METHODS

Literature searches were conducted utilizing Pubmed, with emphasis on human pre- and post-implantation mosaicism.

RESULTS

Mosaicism persists in two separate forms: general and confined. General mosaicism is routine during human embryonic growth as detected by preimplantation genetic screening at either the cleavage or blastocyst stage, leading to mosaicism within both the placenta and fetus proper. Confined mosaicism has been reported in the brain, gonads and placenta, amongst other places. Mosaicism is derived from a variety of mechanisms including chromosome non-disjunction, anaphase lagging or endoreplication. Anaphase lagging has been implicated as the main process by which mosaicism arises in the preimplantation embryo. Furthermore, mosaicism can be caused by any one of numerous factors from paternal, maternal or exogenous factors such as culture media or possibly controlled ovarian hyperstimulation during in vitro fertilization (IVF). Mosaicism has been reported in as high as 70 and 90% of cleavage- and blastocyst-stage embryos derived from IVF, respectively.

CONCLUSIONS

The clinical consequences of mosaicism depend on which chromosome is involved, and when and where an error occurs. Mitotic rescue of a meiotic error or a very early mitotic error will typically lead to general mosaicism while a mitotic error at a specific cell lineage point typically leads to confined mosaicism. The clinical consequences of mosaicism are dependent on numerous aspects, with the consequences being unique for each event.

Evaluation of ovarian reserve in infertile patients

Diminished ovarian reserve is a more common occurrence as more women postpone childbearing in modern societies due to social and demographic trends. Diminished ovarian reserve is one of the primary reasons for poor ART outcome. Due to high costs, side effects and heavy burden on patients on ART treatments, patient selection and counseling for prognosis is an important aspect before starting ART. Proper prediction of ovarian reserve before initiation of the treatment can decrease cycle cancellations, help clinicians to establish alternative treatment options (i.e.oocyte donation) for poor prognosis patients. However, indicators of ovarian reserve are not fully successful in predicting the outcome of the treatment. In this review, our aim was to discuss the efficacy of ovarian reserve tests on predicting poor ovarian response and treatment outcome in ART patients.

Meiotic recombination in human oocytes

Studies of human trisomies indicate a remarkable relationship between abnormal meiotic recombination and subsequent nondisjunction at maternal meiosis I or II. Specifically, failure to recombine or recombination events located either too near to or too far from the centromere have been linked to the origin of human trisomies. It should be possible to identify these abnormal crossover configurations by using immunofluorescence methodology to directly examine the meiotic recombination process in the human female. Accordingly, we initiated studies of crossover-associated proteins (e.g., MLH1) in human fetal oocytes to analyze their number and distribution on nondisjunction-prone human chromosomes and, more generally, to characterize genome-wide levels of recombination in the human female. Our analyses indicate that the number of MLH1 foci is lower than predicted from genetic linkage analysis, but its localization pattern conforms to that expected for a crossover-associated protein. In studies of individual chromosomes, our observations provide evidence for the presence of "vulnerable" crossover configurations in the fetal oocyte, consistent with the idea that these are subsequently translated into nondisjunctional events in the adult oocyte.

Intracytoplasmic sperm injection outcome of women over 39: an analysis of 668 cycles

PURPOSE

To evaluate intracytoplasmic sperm injection (ICSI) outcome of women over age 39 and to determine when to discourage such couples to undergo IVF using their own oocytes.

METHODS

Four hundred ninety-five consecutive women (n=668 cycles) over age 39 were evaluated by year-by-year age increments to discriminate the independent prognostic factors for the achievement of pregnancy.

RESULTS

Although the ovarian hyperstimulation performance (COH) and embryological data were not too diverse, the clinical pregnancy rates per embryo transfer decreased from 26 to 13% from age 40 to 44. According to logistic regression, the female age seems to be the only variable in order to predict an ongoing pregnancy. The miscarriage rate increased with advancing female age. It was 33% at age 40 but increased to 100% by age 45.

CONCLUSIONS

The performance of COH and embryological data is not discouraging among women over 39 years in ICSI cycles. However, increased miscarriages as well as decreased implantation rate are mainly responsible for the poor performance of patients with advanced female age. Irrespective of the ovarian reserve testing, ICSI may be refused at age 45 and thereafter.

Quality management system in PGD/PGS: now is the time

PURPOSE

Governments and international authorities require an accreditation of the PGD/PGS laboratories in order to ensure the safety and reproducibility of these analytical procedures. The implementation of a Quality Management System is the first mandatory step prior to accreditation. Our aim is to offer a detailed guidance to the PGD/PGS community that would like to implement this system in the future.

METHODS

The certification was based on the norm ISO 9001:2000 and requires the identification of procedures, definition of the flowchart, documentation of the processes, recognition of the critical control points, establishment of quality controls, performance of validation and audit system.

RESULTS

The achievement of ISO certification with the specific scope of "preimplantation genetic diagnosis".

CONCLUSION

Certification of PGD/PGS allows to achieve evaluation of the efficiency to ensure the sensitivity and a continuous improvement of the genetic diagnosis of embryonic single cells.

A prospective randomized controlled trial of preimplantation genetic screening in the "good prognosis" patient

OBJECTIVE

To determine whether the routine use of preimplantation genetic screening (PGS) in "good prognosis" women improves in vitro fertilization (IVF) cycle outcome.

DESIGN

Randomized, controlled, prospective clinical study.

SETTING

Private infertility clinic.

PATIENT(S)

Infertile women predicted to have a good prognosis as defined by: age <39 years, normal ovarian reserve, body mass index <30 kg/m(2), presence of ejaculated sperm, normal uterus, <or=2 previous failed IVF cycles.

INTERVENTION(S)

Patients were randomized to the PGS group or the control group on day 3 after oocyte retrieval; 23 women underwent blastomere biopsy on day 3 after fertilization (PGS group), and 24 women underwent routine IVF (control group). All embryos were transferred on day 5 or 6 after fertilization.

MAIN OUTCOME MEASURE(S)

Pregnancy, implantation, multiple gestation, and live birth rates.

RESULT(S)

No statistically significant differences were found between the PGS and control groups with respect to clinical pregnancy rate (52.4% versus 72.7%). However, the embryo implantation rate was statistically significantly lower for the PGS group (31.7% versus 62.3%) as were the live birth rate (28.6% versus 68.2%) and the multiple birth rate (9.1% versus 46.7%).

CONCLUSION(S)

In a "good prognosis" population of women, PGS does not appear to improve pregnancy, implantation, or live birth rates.

Clinical pregnancy and delivery of a healthy baby by a 44-year-old woman after a successful in vitro fertilization frozen cycle using her own oocytes

OBJECTIVE

To present a successful IVF frozen-embryo replacement cycle in a 44-year-old woman, using her own oocytes.

DESIGN

Case report.

SETTING

Assisted reproduction unit in a university hospital.

PATIENT(S)

A 44-year-old woman underwent IVF frozen-embryo replacement cycle after three unsuccessful IVF fresh cycles with her own oocytes. The couple were unable to achieve pregnancy for 4 years and were advised to have IVF because of the long duration of subfertility and woman's age.

INTERVENTION(S)

In vitro fertilization.

MAIN OUTCOME MEASURE(S)

Pregnancy, live birth, baseline FSH on day 3, and IVF outcome.

RESULT(S)

The woman achieved pregnancy through a frozen-embryo replacement cycle and gave birth to a healthy girl who weighed 3,330 g.

CONCLUSION(S)

Pregnancy is difficult to achieve for women >40 years of age and especially so for a woman at the age of 44 years. In vitro fertilization cycles may not lead to the desired result, but the availability of a frozen embryo replacement cycle is associated with better prognosis.

A new approach to ovarian reserve testing

OBJECTIVE

To critically examine ovarian reserve testing before assisted reproduction.

DESIGN

A PUBMED computer search to identify relevant literature.

SETTING

Multiple sites.

PATIENT(S)

Patients undergoing assisted reproduction.

INTERVENTION(S)

Testing for ovarian reserve.

MAIN OUTCOME MEASURE(S)

Assisted reproductive technology (ART) and pregnancy outcomes.

RESULT(S)

The prevalence of ovarian insufficiency varies significantly for women aged 30-45 years. Generalization or averaging of threshold values across different aged women leads to very poor sensitivity, specificity, and positive predictive value for all tests of ovarian reserve. Because of the changing prevalence of ovarian insufficiency, there is no single, suitable threshold value for any screening test of ovarian reserve. Our analysis supports dividing impaired ovarian reserve into two groups: age-dependent ovarian aging (physiologic) and premature (nonphysiologic) reductions in the oocyte pool. Interpretation of any screening test used requires that age is considered as a variable. To guide clinical interpretation of test results, we suggest using a nomogram of FSH values versus expected delivery rate-per-cycle-start with ART for a given age.

CONCLUSION(S)

Proper interpretation of screening tests for ovarian insufficiency in couples considering ART is important as the presence of impaired ovarian reserve is associated with a low likelihood of pregnancy. The condition of premature (nonphysiologic) ovarian insufficiency warrants additional research.

Preimplantation genetic screening: "established" and ready for prime time?

Unless attempts to improve pregnancy rates and/or diminish miscarriage rates through preimplantation genetic screening (PGS) are applied to only carefully selected patients, they will fail. Because specific PGS indications have remained undefined, PGS should be considered an experimental procedure.

Live birth following preimplantation genetic screening for trisomy 21. Should aneuploidy screening be offered to all older patients undergoing IVF?

A 42-year-old female patient with history of secondary infertility was referred to our assisted conception unit for in vitro fertilization (IVF). Before her referral, she had two cycles of IVF at another centre; the first was unsuccessful and, after conceiving at the second attempt, the pregnancy was terminated at 14 weeks' gestation following a positive nuchal translucency scan and a diagnosis of trisomy 21 (Down syndrome) by a chorionic villous biopsy performed in the first trimester. The screening tests for trisomy 21 were offered to the patient in view of her advanced age. Subsequent karyotyping revealed that both partners had a normal chromosomal complement. Following genetic counselling, the couple were offered IVF treatment along with preimplantation genetic screening for trisomy 21. Four of the five embryos were suitable for biopsy, and one blastomere from each embryo was analyzed using fluorescent in situ hybridization for chromosome 21. The analysis revealed that two embryos had trisomy 21, one had monosomy 21, and only one embryo was diploid for chromosome 21. The single diploid embryo was transferred to the uterus on day 3, and resulted in an uneventful pregnancy and delivery of a healthy live-born male.

Pregnancy loss in the first in vitro fertilization cycle is not predictive of subsequent delivery in women over 40 years

OBJECTIVE

To determine if there is an association between first IVF cycle outcome and subsequent delivery rate for women over 40 years.

DESIGN

Retrospective data analysis.

SETTING

Large, private academically affiliated IVF center.

INTERVENTION(S)

Patients over 40 years of age undergoing IVF.

MAIN OUTCOME MEASURE(S)

Delivery rate compared between patients with a pregnancy loss versus a negative beta-hCG in their first cycle. Additional factors including subsequent pregnancy losses, total number of IVF cycles, and delivery rates per cycle were also analyzed.

RESULT(S)

Among women who underwent their first IVF cycle over age 40, 8% of women had a pregnancy loss and 82% had a negative beta-hCG in their initial IVF cycle. In the pregnancy loss and negative beta-hCG groups, 17.9% and 21.9%, respectively, had a successful delivery in a future cycle. There were no further pregnancies leading to delivery after the fourth treatment cycle for the pregnancy loss group and the sixth treatment cycle for the negative beta-hCG group. The average number of cycles and the number of subsequent pregnancy losses were similar in both groups.

CONCLUSION(S)

Outcome of initial IVF cycle is not prognostic of future delivery for women over the age of 40 years.

A simplified technique for embryo biopsy for preimplantation genetic diagnosis

OBJECTIVE

To report a simplified embryo biopsy method for preimplantation genetic diagnosis (PGD).

DESIGN

Technique and method.

SETTING

A regional hospital in vitro fertilization (IVF) laboratory and private reproductive medicine clinic.

PATIENT(S)

Women undergoing IVF and PGD.

INTERVENTION(S)

Blastomeres were successfully isolated from day-3 embryos at various stages.

MAIN OUTCOME MEASURE(S)

Blastomere integrity after biopsy, time of biopsy procedure, and subsequent blastocyst developmental rate.

RESULT(S)

Twenty embryos derived from abnormally fertilized oocytes (one pronucleus or three pronuclei) were used for biopsy at four-cell to 10-cell stages (day 3) by a laser zona drilling and assisted hatching micropipette delivery of culture medium inside the zona to push one blastomere out. Biopsies of all embryos using this method were successful. In two cases for PGD, fourteen 6-9-cell and four 3-4-cell stage embryos were successfully biopsied by this method. Ten out of 14 embryos from the 6-9-cell stage developed to hatching or hatched blastocysts. When two hatched blastocysts were vitrified, warmed, and cultured, both reexpanded, showing normal morphologic features.

CONCLUSION(S)

This technique is easy to learn, less damaging to the embryos, and less time consuming. It can be used for all stages of embryos without damage to either embryos or isolated blastomeres. It is an alternative method for embryo biopsy in PGD.

Prise en charge en Assistance médicale à la procréation des femmes de 38 ans et plus: résultats d'une enquête à propos de 84 couples

OBJECTIVE

More and more young women are delaying childbearing until the fourth decade of life: thus, Assisted Reproductive Techniques centres receive more and more requests from ageing women. The aim of the study is to analyse the purpose of these requests, the biological and clinical features of these patients and the results in our infertility centre.

PATIENTS AND METHODS

A retrospective study was carried out at the CHU of Saint-Etienne from 01.01.01 to 31.12.04. We analysed the social, clinical and biological features of 84 couples when the woman's age was equal or superior to 38 years, representing 218 cycles. A questionnaire was used to collect social data.

RESULTS

Several factors can explain the increasing number of ageing women consulting for infertility: extend university time and professional career, professional stability, contraception and late meeting of the partner, false reassuring information concerning progress in ART, second child desire after a late first pregnancy, but also second marital unions and child desire in the redefined couple. In our study, above 40 years old, the pregnancy (19.4 versus 10.5%) and delivery rates (16.7 versus 5.8%) clearly decreased in IUI. Thus, most of the clinicians propose, in first choice, an IVF cycle to a 40 year-old woman. The ultrasound measurement of antral follicle count can accurately evaluate the prognosis in terms of pregnancy (P<0.01) and delivery rate (P=0.03). For patients with unfavourable prognosis, oocyte donation, embryo donation, or adoption can be considered.

DISCUSSION AND CONCLUSION

ART cannot compensate for the natural decrease in pregnancy rates and the increase in early miscarriages in ageing women. Therefore, it is essential to inform young women of the negative effects of age on their potential fertility.

Preimplantation genetic diagnosis

Preimplantion genetic diagnosis (PGD) is now used for identification of gene and chromosomal defects in embryos. In this article we describe its use primarily for identification of chromosomal defects in women with recurrent abortions, repeated in vitro fertilization (IVF) failure, and advanced maternal age. In all these situations there is increase in chromosomal defects. The identification of normal embryos and the elimination of abnormal embryos are argued to be helpful in increasing implantation and pregnancy rates in these women.

Preimplantation genetic diagnosis in assisted reproduction

Despite its novelty, preimplantation genetic diagnosis has become an alternative to traditional prenatal diagnosis, allowing the establishment of only unaffected pregnancies and avoiding the risk of pregnancy termination. In addition, preimplantation genetic diagnosis is presently applied for much wider indications than prenatal diagnosis, including common diseases with genetic predisposition and preimplantation human leukocyte antigen typing, with the purpose of establishing potential donor progeny for stem cell treatment of siblings. Many hundreds of apparently healthy, unaffected children have been born after preimplantation genetic diagnosis, presenting evidence of its accuracy, reliability and safety. Preimplantation genetic diagnosis appears to be of special value for avoiding age-related aneuploidies in patients of advanced reproductive age, improving reproductive outcome, particularly obvious from their reproductive history, and is presently an extremely attractive option for carriers of balanced translocations to have unaffected children of their own.

Screening oocytes by polar body biopsy

Preimplantation genetic aneuploidy screening performed by polar body biopsy has become a frequently used method, especially as in several countries only preconceptional genetic diagnosis is allowed. To penetrate the zona pellucida, mechanical, chemical and laser-assisted techniques have been introduced. In this paper, the advantages, disadvantages, efficacy and safety of these techniques are elucidated.

Safety of drugs used in assisted reproduction techniques

Infertility may affect one in six couples; however, the development of the assisted reproduction technique (ART) created the opportunity for a large proportion of the infertile population to bear children. Pharmacological agents are routinely used in ART, and new ones are introduced regularly, with the aim of retrieving multiple oocytes to increase the prospect of pregnancy. The combinations of drugs that are used have specific adverse effects, but it is mostly the combined action of more than one agent that causes the greatest concern. The matter is complicated by the suspicion that some techniques in ART, for example intracytoplasmic sperm injection for severe male infertility problems (including azoospermia), may also contribute to the increase in adverse effects, especially congenital malformation. Gonadotropin releasing hormone (GnRH) agonists are widely used in controlled ovarian hyperstimulation. It may give rise to a short period of estradiol withdrawal symptoms and it may also lead to luteal phase deficiency. Similarly GnRHa antagonists, which have been recently introduced to control ovarian hyperstimulation, can lead to luteal phase deficiency and may cause some local injection site reactions. The more pure form of gonadotropin leads to less local injection site reactions and their main adverse effects are associated with the consequences of multiple ovulations. It has been proposed that gonadotropins may be a factor in the increasing risk of ovarian cancer and possibly breast cancer, but this has not been substantiated. Prion infection is another potential hazard, although no cases have been reported. Ovarian hyperstimulation syndrome is a well recognised complication of controlled ovarian hyperstimulation in ART. It is usually a result of recruitment of a large number of ovarian follicles. Efforts to minimise the incidence of this syndrome and its severity are now well developed. Congenital malformations are another possible adverse effect of fertility drugs, but it is more probable that the increase in congenital abnormality that is reported in ART is because of the population studied, i.e. patients already at high risk of congenital malformation, rather than the fertility drugs used or the technique employed. High order multiple pregnancy and its sequela is a well established complication of controlled ovarian hyperstimulation. This could be a result of multiple ovulations or more than one embryo replacement. Reducing the number of embryos transferred can reduce this more serious adverse effect for expectant mothers and for children conceived from ART.

The importance of aneuploidy screening in reciprocal translocation carriers

The purpose of this study is to investigate the aneuploidy rate and the mosaicism of chromosomes not involved in reciprocal translocations. Aneuploidy screening (AS) (13, 16, 18, 21 and 22) was performed as a re-analysis on fixed blastomeres from 126 embryos already analysed in preimplantation genetic diagnosis (PGD) cycles of eight female and five male reciprocal translocation carriers who had not achieved a pregnancy. A successful diagnosis for AS was achieved in 91.3% of embryos; 30.9% were euploid and 60.3% were aneuploid for the five chromosomes analysed. Of the embryos, 8.7% were euploid for AS and normal-balanced for the translocation and 22.2% were euploid for AS but unbalanced for the translocation; 8% of the embryos were aneuploid for AS but normal-balanced for the translocation and 52.4% were aneuploid for AS and also unbalanced for the translocation. At least 58.7% of the embryos were mosaic regarding mosaicism for the chromosomes involved and not involved in the translocations. Six of the 16 embryos transferred in the PGD cycles were aneuploid for the AS study; four of them were also mosaics. AS should be performed in reciprocal translocation carriers after segregation analysis in PGD.

Aneuploidy screening in a coelomic sample from a missed abortion using sequential fluorescence in situ hybridization

OBJECTIVE

To investigate the incidence of aneuploidy by using sequential interphase fluorescence in situ hybridization (FISH) in an uncultured coelomic fluid sample from a missed abortion.

DESIGN

Case report.

SETTING

Fetal medicine and gynecology departments of two university hospitals.

PATIENT(S)

A 33-year-old woman with a missed abortion.

INTERVENTION(S)

Molecular cytogenetic analysis was performed on coelomic fluid cells and placental tissue by applying a multicolor probe for chromosomes 13, 16, 18, 21, and 22 in a first layer of hybridization, followed by a triple-color probe for chromosomes X, Y, and 18.

MAIN OUTCOME MEASURE(S)

Analysis of limited number of coelomic cells by using sequential FISH.

RESULT(S)

The results showed trisomy 13 in 92% of nuclei. Diploid cells were observed at low levels (4%), but these were caused by maternal cell contamination, as revealed after reprobing with the X,Y,18 triple-color probe set. The result also was confirmed in the placental tissue.

CONCLUSION(S)

We conclude that sequential FISH analysis can overcome problems associated with limited cell numbers, accurately detect aneuploidy, and distinguish between maternal cell contamination and genuine mosaicism in coelomic cells and placental tissue from missed abortions. It also has the potential to be applied for rapid aneuploidy screening in clinical cases after coelocentesis and to be used for follow-up analysis of pregnancies established after preimplantation genetic screening.

IVF results: optimize not maximize

The desire to improve in vitro fertilization (IVF) results has led clinicians to replace more than 1 embryo in the uterus. As a result, multiple births have increased over the last 2 decades to epidemic proportions, exposing the field of assisted conception to justified criticism. This review aims to ensure that physicians involved in the field of fertility treatment are aware of the risks and complications related to multiple pregnancies, and to explore possible strategies such as blastocyst culture, preimplantation genetic screening, and embryo cryopreservation, which can help to control and reverse the tide of multiple pregnancies without reducing the good success rate that modern IVF treatment enjoys. A brief overview of the respective UK legislative system is also presented.

Ambivalent attitudes towards pre-implantation genetic diagnosis in Germany

BACKGROUND

Pre-implantation genetic diagnosis (PGD) is a modern technique in reproductive medicine which can be used to diagnose genetic disorders of an embryo. PGD is currently not legal in Germany, still there are debates being held regarding the issue of legalization. Both the internationally "accepted" indications and new or alternative approaches can lead to complex ethical dilemmas. The attitudes towards PGD have rarely been assessed in the general population.

METHODS

In our study, 2110 persons aged 18-50 years were interviewed about their attitudes towards PGD and related topics. We assumed that religion, world views and the evaluation of PGD would influence the attitude a person has towards this procedure.

RESULTS AND CONCLUSIONS

In our survey, the majority of respondents would agree to a restricted legalization of PGD in Germany. Our results also confirmed some of our assumptions but religion did not have the expected influence. The evaluation of costs and benefits of PGD and the feelings associated with this technique explained more of the final attitude whether PGD should remain prohibited in Germany or not. The agreement to a restricted legalization may be connected to an overall rejection of prohibitions made by the state concerning the individual reproductive autonomy.

Strategies and clinical outcome of 250 cycles of Preimplantation Genetic Diagnosis for single gene disorders

BACKGROUND

We report on our experience with preimplantation genetic diagnosis (PGD) for single gene disorders (SGDs), from 1999 to 2004, describing strategies and overall clinical outcome of 250 cycles in 174 couples for 23 different genetic conditions.

METHODS

PGD cycles included 15 for autosomal dominant, 148 for autosomal recessive and 19 for X-linked SGDs. In addition, 68 cycles of PGD for SGDs were performed in combination with HLA matching. The strategy in each case used an initial multiplex PCR, followed by minisequencing to identify the mutation(s) combined with multiplex PCR for closely linked informative markers to increase accuracy. Linkage analysis, using intragenic and/or extragenic polymorphic microsatellite markers, was performed in cases where the disease-causing mutation(s) was unknown or undetectable.

RESULTS

In 250 PGD cycles, a total of 1961 cleavage stage embryos were biopsied. PCR was successful in 3409 out of 3149 (92.4%) biopsied blastomeres and a diagnosis was possible in 1849 (94.3%) embryos. Four hundred and twenty-seven embryos were transferred in 211 cycles, resulting in 71 pregnancies (33.6% per embryo transfer), including 15 biochemical pregnancies, six spontaneous miscarriages, two ectopic pregnancies, which were terminated, and nine pregnancies which are still ongoing. The remaining pregnancies were confirmed to be unaffected and went to term without complications, resulting in the birth of 35 healthy babies.

CONCLUSIONS

Minisequencing for mutation detection combined with multiplex fluorescence PCR for linkage analysis is an efficient, accurate and widely applicable strategy for PGD of SGDs. Our experience provides a further demonstration that PGD is an effective clinical tool and a useful option for many couples with a high risk of transmitting a genetic disease.

One last chance for pregnancy: a review of 2,705 in vitro fertilization cycles initiated in women age 40 years and above

OBJECTIVE

To describe live birth rates and predictors of success in 1-year age increments for women > or =40 years when initiating assisted reproductive technologies (ART).

DESIGN

Retrospective database analysis.

SETTING

A large university-affiliated infertility center.

PATIENT(S)

One thousand two hundred sixty-three women undergoing 2,705 ART cycles at age 40 or above.

INTERVENTION(S)

Couples undergoing ART.

MAIN OUTCOME MEASURE(S)

Pregnancy and live birth rates per cycle start were determined based on 1-year increments in women aged > or =40. Predictors of success, including number of embryos transferred, number of fetal heartbeats, availability of embryos for cryopreservation, and cycle day 3 FSH levels, were analyzed.

RESULT(S)

The overall live birth rate per cycle start was 9.7%. Cumulative live birth rates in women ranged from 28.4% if starting ART at age 40 to 0 by age 46. The overall spontaneous abortion rate was 32.6% (range, 23.9%-66.7%). Higher pregnancy rates were predicted by the greater number of embryos available for transfer, by the availability of excess embryos for cryopreservation, and by the presence of two fetal heartbeats on ultrasound. The outcome of the first IVF cycle did not predict the outcome of subsequent cycles.

CONCLUSION(S)

Assisted reproductive technology has a reasonable chance for success (>5%) up until the end of the forty-third year. Twins on initial ultrasound, large numbers of embryos available for transfer, and the presence of excess embryos for cryopreservation predict higher live birth rates.

Place of preimplantation diagnosis in genetic practice

Preimplantation genetic diagnosis (PGD) is currently one of the practical options available for couples at-risk to avoid the birth of children with genetic and chromosomal disorders. Despite its novelty, PGD has already become an alternative to traditional prenatal diagnosis, allowing establishing only unaffected pregnancies avoiding the risk for pregnancy termination. Indications for PGD have currently expanded beyond those practices in prenatal diagnosis, such as late-onset diseases with genetic predisposition, and preimplantation HLA typing with the purpose of establishing potential donor progeny for stem cell treatment of siblings, which makes PGD also an important compliment to prenatal diagnosis. The fact that more than 1,000 apparently healthy unaffected children have been born after PGD suggests its accuracy, reliability, and safety. PGD is presently an excellent option for carriers of balanced translocations, and appears to be of special value for avoiding age-related aneuploidies in patients of advanced reproductive age. The accumulated experience of thousands of PGD cycles for poor prognosis in vitro fertilization (IVF) patients provides strong evidence of the improvement of clinical outcome, particularly obvious from the reproductive history of patients. This makes of practical relevance to inform couples at-risk about availability of PGD option, so they make their own choice in avoiding the birth of affected offspring and having healthy children of their own.

Fertility preservation in breast cancer patients: a prospective controlled comparison of ovarian stimulation with tamoxifen and letrozole for embryo cryopreservation

PURPOSE

To develop safe ovarian stimulation methods to perform in vitro fertilization (IVF) in breast cancer patients who wish to preserve their fertility via embryo cryopreservation before chemotherapy.

PATIENTS AND METHODS

Sixty women (age range, 24 to 43 years) with breast cancer were prospectively studied. Twenty-nine patients underwent 33 ovarian stimulation cycles with either tamoxifen 60 mg/d alone (Tam-IVF) or in combination with low-dose follicle-stimulating hormone (TamFSH-IVF) or letrozole 5 mg in combination with FSH (Letrozole-IVF). After IVF, all resultant embryos were cryopreserved to preserve fertility. Recurrence rates were compared with controls (n = 31) who elected not to undergo IVF.

RESULTS

Compared with Tam-IVF, both TamFSH-IVF and Letrozole-IVF patients had greater numbers of follicles (2 +/- 0.3 v 6 +/- 1 and 7.8 +/- 0.9, respectively; P < .0001), mature oocytes (1.5 +/- 0.3 v 5.1 +/- 1.1 and 8.5 +/- 1.6, respectively; P < .001), and embryos (1.3 +/- 0.2 v 3.8 +/- 0.8 and 5.3 +/- 0.8, respectively; P < .001). Peak estradiol (E2) levels were lower with Letrozole-IVF and Tam-IVF compared with TamFSH-IVF. After 554 +/- 31 days (range, 153 to 1,441 days) of follow-up, cancer recurrence rate was similar between IVF and control patients (three of 29 v three of 31 patients, respectively; hazard ratio, 1.5; 95% CI, 0.29 to 7.4), and this estimate was not affected by cancer stage.

CONCLUSION

The combination of low-dose FSH with tamoxifen (TamFSH-IVF) or letrozole (Letrozole-IVF) results in higher embryo yield compared with Tam-IVF. Recurrence rates do not seem to be increased, but the letrozole protocol may be preferred because it results in lower peak E2 levels.

Preimplantation diagnosis: a realistic option for assisted reproduction and genetic practice

PURPOSE OF REVIEW

Preimplantation genetic diagnosis (PGD) allows genetically disadvantaged couples to reproduce, while avoiding the birth of children with targeted genetic disorders. By ensuring unaffected pregnancies, PGD circumvents the possible need and therefore risks of pregnancy termination. This review will describe the current progress of PGD for Mendelian and chromosomal disorders and its impact on reproductive medicine.

RECENT FINDINGS

Indications for PGD have expanded beyond those used in prenatal diagnosis, which has also resulted in improved access to HLA-compatible stem-cell transplantation for siblings through preimplantation HLA typing. More than 1000 apparently healthy, unaffected children have been born after PGD, suggesting its accuracy, reliability and safety. PGD is currently the only hope for carriers of balanced translocations. It also appears to be of special value for avoiding age-related aneuploidies in in-vitro fertilization patients who have a particularly poor prognosis for a successful pregnancy; the accumulated experience of thousands of PGD cycles strongly suggests that PGD can improve clinical outcome for such patients.

SUMMARY

PGD would particularly benefit poor prognosis in-vitro fertilization patients and other at-risk couples by improving reproductive outcomes and avoiding the birth of affected offspring.

Spindle abnormalities in normally developing and arrested human preimplantation embryos in vitro identified by confocal laser scanning microscopy

BACKGROUND

Despite recent technical improvements, many human preimplantation embryos fail to develop to the blastocyst stage or implant after transfer to the uterus. A possible cause for this developmental arrest is the high incidence of nuclear and postzygotic chromosomal abnormalities observed during cleavage, including chaotic chromosome complements, suggestive of defects in mitotic chromosomal segregation. The underlying mechanisms are largely unknown, but similarities with chromosome instability in human cancers led to the proposal that cell cycle checkpoints may not operate at these early stages.

METHODS

To investigate this and to examine whether spindle abnormalities contribute to chromosome malsegregation, we have used fluorescence and confocal laser scanning microscopy, following immunolabelling with antibodies specific for alpha-tubulin, gamma-tubulin, or acetylated tubulin, combined with a DNA fluorochrome to visualize nuclei, spindle and chromosome configurations in normal and arrested human embryos, from cleavage to blastocyst stages.

RESULTS

In addition to frequent interphase nuclear abnormalities, we identify for the first time various spindle abnormalities including abnormal shape and chromosome loss and multipolar spindles at cleavage and blastocyst stages.

CONCLUSIONS

We propose that a major pathway leading to postzygotic chromosomal abnormalities is the formation of binucleate blastomeres with two centrosomes which result either in a bipolar spindle and division to two tetraploid blastomeres, or in a multipolar spindle, chromosome malsegregation and chromosomal chaos.

Preimplantation diagnosis (PGD)--a European clinician's point of view

This paper describes the current status of preimplantation diagnosis from the viewpoint of an experienced clinician specialized in reproductive medicine. Current progress and international experiences with different applications and techniques are being reviewed on the basis of the literature. Particular interest is focused on possible advantages of routinely diagnosing major chromosome aneuploidies in preimplantation-embryos of patients undergoing in vitro fertilization and embryo transfer. Last but not least, a short survey of the international guidelines and legislation is compared to the situation in the author's country, Austria, where it is currently unclear whether preimplantation diagnosis is allowed or not.

Preimplantation genetic diagnosis

Preimplantation genetic diagnosis (PGD) was introduced at the beginning of the 1990s as an alternative to prenatal diagnosis, to prevent termination of pregnancy in couples with a high risk for offspring affected by a sex-linked genetic disease. At that time, embryos obtained in vitro were tested to ascertain their sex, and only female embryos were transferred. Since then, techniques for genetic analysis at the single-cell level, involving assessment of first and second polar bodies from oocytes or blastomeres from cleavage-stage embryos, have evolved. Fluorescence in-situ hybridisation (FISH) has been introduced for the analysis of chromosomes and PCR for the analysis of genes in cases of monogenic diseases. In-vitro culture of embryos has also improved through the use of sequential media. Here, we provide an overview of indications for, and techniques used in, PGD, and discuss results obtained with the technique and outcomes of pregnancies. A brief review of new technologies is also included.

Thirteen years' experience of preimplantation diagnosis: report of the Fifth International Symposium on Preimplantation Genetics

Preimplantation genetic diagnosis (PGD) has been further developed into a practical option for avoiding the birth of affected children, representing an important complement to traditional prenatal diagnosis. More than 1000 unaffected children have been born after PGD, suggesting the accuracy and safety of the procedure, which is currently also used with the establishment of potential donor progeny for stem cell treatment of siblings. Together with progress in the establishment of embryonic stem (ES) cells, this may contribute to the development and application of stem cell therapy. The accumulated experience of thousands of PGD cycles for poor prognosis IVF patients provides further evidence of the improvement of clinical outcome, particularly obvious from the reproductive history of PGD patients. A high prevalence of aneuploidies in oocytes and embryos may affect the accuracy of PGD for single gene disorders, making aneuploidy testing an important part of PGD for causative genes and preimplantation human leukocyte antigen (HLA) typing. A sequential sampling of both oocytes and the resulting embryos may improve accuracy of aneuploidy testing and may also allow the detection and avoidance of transfer of embryos with uniparental disomies. Current developments and application of nuclear transfer and sperm duplication techniques, and microarray technology, may also contribute to the improvement of PGD and help in the development of PGD for genetic expression disorders.

Factors that determine discordant outcome from shared oocytes

OBJECTIVE

To investigate the factors that may be related to pregnancy in oocyte recipients who shared oocytes from the same donor and showed discordant pregnancy outcome.

DESIGN

Matched pair analysis.

SETTING

IVF academic center.

PATIENT(S)

Five hundred forty-two oocyte donation cycles that shared oocytes from 197 donors with discordant outcome.

INTERVENTION(S)

Egg donation and embryo transfer.

MAIN OUTCOME MEASURE(S)

Pregnancy rate and implantation rate.

RESULT(S)

Three hundred sixty-five matched-paired discordant outcome oocyte recipients were analyzed. Pregnant and nonpregnant recipients were similar in terms of age, serum E(2) levels, endometrial thickness, indications for oocyte donation, and abnormal sperm parameters. No differences were found in the number of oocytes received per patient, fertilization rate, IVF/intracytoplasmic sperm injection (ICSI) distribution, embryo quality, or on embryo transfer difficulty.

CONCLUSION(S)

Discordant pregnancy outcome could not be explained by the different egg recipients and cycle factors studied. In addition to chance, other factors must be investigated that could explain discordant outcome in egg recipients sharing oocytes from single donors.

The role of preimplantation genetic diagnosis in women of advanced reproductive age

PURPOSE OF REVIEW

More than half of in-vitro fertilization patients are of advanced reproductive age and at risk for producing offspring with age-related aneuploidies, which contribute significantly to spontaneous abortions and implantation failure.

RECENT FINDINGS

Fluorescent in-situ hybridization analysis of thousands of oocytes and preimplantation embryos obtained from these patients revealed an aneuploidy rate of over 50%, suggesting practical relevance of preimplantation genetic diagnosis for aneuploidy to women of advanced reproductive age. The overall preimplantation genetic diagnosis experience for age-related aneuploidies comprising more than 3000 clinical cycles indicates the positive impact of preselection and transfer of aneuploidy-free embryos on implantation and pregnancy rates and outcome of pregnancies in women of advanced reproductive age.

SUMMARY

These patients will need to be informed about preimplantation genetic diagnosis availability, in order use this option to improve their relatively poor chances of becoming pregnant, especially with the current tendency of limiting the number of transferred embryos to avoid complications due to multiple pregnancies. This may contribute significantly to improving standards of assisted reproduction technology, substituting the current practice of selection of embryos for transfer using morphological parameters with the preselection of aneuploidy-free embryos with a higher potential to result in pregnancy.