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1.
Fertil Steril ; 113(5): 1080-1089.e2, 2020 05.
Article in English | MEDLINE | ID: mdl-32276763

ABSTRACT

OBJECTIVE: To determine whether human oocytes possess a checkpoint to prevent completion of meiosis I when DNA is damaged. DESIGN: DNA damage is considered a major threat to the establishment of healthy eggs and embryos. Recent studies found that mouse oocytes with damaged DNA can resume meiosis and undergo germinal vesicle breakdown (GVBD), but then arrest in metaphase of meiosis I in a process involving spindle assembly checkpoint (SAC) signaling. Such a mechanism could help prevent the generation of metaphase II (MII) eggs with damaged DNA. Here, we compared the impact of DNA-damaging agents with nondamaged control samples in mouse and human oocytes. SETTING: University-affiliated clinic and research center. PATIENT(S): Patients undergoing ICSI cycles donated GV-stage oocytes after informed consent; 149 human oocytes were collected over 2 years (from 50 patients aged 27-44 years). INTERVENTIONS(S): Mice and human oocytes were treated with DNA-damaging drugs. MAIN OUTCOME MEASURE(S): Oocytes were monitored to evaluate GVBD and polar body extrusion (PBE), in addition to DNA damage assessment with the use of γH2AX antibodies and confocal microscopy. RESULT(S): Whereas DNA damage in mouse oocytes delays or prevents oocyte maturation, most human oocytes harboring experimentally induced DNA damage progress through meiosis I and subsequently form an MII egg, revealing the absence of a DNA damage-induced SAC response. Analysis of the resulting MII eggs revealed damaged DNA and chaotic spindle apparatus, despite the oocyte appearing morphologically normal. CONCLUSION(S): Our data indicate that experimentally induced DNA damage does not prevent PBE in human oocytes and can persist in morphologically normal looking MII eggs.


Subject(s)
DNA Damage , Meiosis , Oocytes/pathology , Adult , Animals , Carbazoles/toxicity , Cells, Cultured , Etoposide/toxicity , Female , Histones/metabolism , Humans , Mice , Oocytes/drug effects , Oocytes/metabolism , Polar Bodies/pathology , Pyrimidines/toxicity , Species Specificity , Spindle Apparatus/pathology , Thiones/toxicity , Time Factors
3.
J Obstet Gynaecol Can ; 40(1): 94-114, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29274714

ABSTRACT

OBJECTIVE: The objective of the Canadian HIV Pregnancy Planning Guidelines is to provide clinical information and recommendations for health care providers to assist Canadians affected by HIV with their fertility, preconception, and pregnancy planning decisions. These guidelines are evidence- and community-based and flexible and take into account diverse and intersecting local/population needs based on the social determinants of health. INTENDED OUTCOMES: EVIDENCE: Literature searches were conducted by a librarian using the Medline, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase databases for published articles in English and French related to HIV and pregnancy and HIV and pregnancy planning for each section of the guidelines. The full search strategy is available upon request. VALUES: The evidence obtained was reviewed and evaluated by the Infectious Diseases Committee of the SOGC under the leadership of the principal authors, and recommendations were made according to the guidelines developed by the Canadian Task Force on Preventive Health Care and through use of the Appraisal of Guidelines Research and Evaluation instrument for the development of clinical guidelines. BENEFITS, HARMS, AND COSTS: Guideline implementation should assist the practitioner in developing an evidence-based approach for the prevention of unplanned pregnancy, preconception, fertility, and pregnancy planning counselling in the context of HIV infection. VALIDATION: These guidelines have been reviewed and approved by the Infectious Disease Committee and the Executive and Council of the SOGC. SPONSOR: Canadian Institutes of Health Research Grant Planning and Dissemination grant (Funding Reference # 137186), which funded a Development Team meeting in 2016.


Subject(s)
Family Planning Services , HIV Infections , Preconception Care , Anti-Retroviral Agents/therapeutic use , Disease Transmission, Infectious/prevention & control , Female , Humans , Pregnancy , Reproductive Techniques, Assisted
4.
Hum Reprod ; 32(6): 1293-1303, 2017 06 01.
Article in English | MEDLINE | ID: mdl-28449121

ABSTRACT

STUDY QUESTION: What are the chromosome segregation errors in human oocyte meiosis-I that may underlie oocyte aneuploidy? SUMMARY ANSWER: Multiple modes of chromosome segregation error were observed, including tri-directional anaphases, which we attribute to loss of bipolar spindle structure at anaphase-I. WHAT IS KNOWN ALREADY: Oocyte aneuploidy is common and associated with infertility, but mechanistic information on the chromosome segregation errors underlying these defects is scarce. Lagging chromosomes were recently reported as a possible mechanism by which segregation errors occur. STUDY DESIGN, SIZE, DURATION: Long-term confocal imaging of chromosome dynamics in 50 human oocytes collected between January 2015 and May 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Germinal vesicle (GV) stage oocytes were collected from women undergoing intracytoplasmic sperm injection cycles and also CD1 mice. Oocytes were microinjected with complementary RNAs to label chromosomes, and in a subset of oocytes, the meiotic spindle. Oocytes were imaged live through meiosis-I using confocal microscopy. 3D image reconstruction was used to classify chromosome segregation phenotypes at anaphase-I. Segregation phenotypes were related to spindle dynamics and cell cycle timings. MAIN RESULTS AND THE ROLE OF CHANCE: Most (87%) mouse oocytes segregated chromosomes with no obvious defects. We found that 20% of human oocytes segregated chromosomes bi-directionally with no lagging chromosomes. The rest were categorised as bi-directional anaphase with lagging chromosomes (20%), bi-directional anaphase with chromatin mass separation (34%) or tri-directional anaphase (26%). Segregation errors correlated with chromosome misalignment prior to anaphase. Spindles were tripolar when tri-directional anaphases occurred. Anaphase phenotypes did not correlate with meiosis-I duration (P = 0.73). LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Oocytes were recovered at GV stage after gonadotrophin-stimulation, and the usual oocyte quality caveats apply. Whilst the possibility that imaging may affect oocyte physiology cannot be formally excluded, detailed controls and justifications are presented. WIDER IMPLICATIONS OF THE FINDINGS: This is one of the first reports of live imaging of chromosome dynamics in human oocytes, introducing tri-directional anaphases as a novel potential mechanism for oocyte aneuploidy. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by grants from Fondation Jean-Louis Lévesque (Canada), CIHR (MOP142334) and CFI (32711) to GF. JH is supported by Postdoctoral Fellowships from The Lalor Foundation and CIHR (146703). The authors have no conflict of interest.


Subject(s)
Anaphase , Aneuploidy , Chromosome Segregation , Oocytes/pathology , Oogenesis , Animals , Animals, Outbred Strains , Cells, Cultured , Female , Humans , Imaging, Three-Dimensional , Infertility, Female/pathology , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Mice , Microinjections , Microscopy, Confocal , Microscopy, Fluorescence , Oocytes/cytology , Oocytes/metabolism , RNA Interference , RNA, Complementary/metabolism , Recombinant Fusion Proteins/metabolism , Specific Pathogen-Free Organisms , Spindle Apparatus/metabolism , Spindle Apparatus/pathology , Time-Lapse Imaging
5.
Fertil Steril ; 104(6): 1419-25, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26361207

ABSTRACT

OBJECTIVE: To compare the outcomes of controlled ovarian stimulation/in vitro fertilization cycles using 450 IU and 600 IU gonadotropin per day in women at risk of poor ovarian response. DESIGN: Prospective randomized controlled nonblinded study. SETTING: University-affiliated private IVF center. PATIENT(S): Women considered to be at risk of poor ovarian response: aged <41 years with basal FSH >10 IU/L, antimüllerian hormone <1 ng/mL, antral follicle count ≤ 8, or a previous IVF cycle with ≥ 300 IU/d gonadotropin that resulted in a cancellation, <8 follicles, or <5 oocytes. INTERVENTION(S): A total of 356 patients underwent a microdose GnRH agonist flare-up IVF/intracytoplasmic sperm injection protocol with a fixed daily dose of either 450 IU FSH (n = 176) or 600 IU FSH (n = 180) equally divided between Menopur and Bravelle. MAIN OUTCOME MEASURE(S): Number of mature oocytes retrieved. RESULT(S): The two groups were similar in terms of age, ovarian reserve, cause of infertility, duration of stimulation, and cycle cancellation rate. There were no significant differences in the number of metaphase II oocytes retrieved (4 [range 0-6] vs. 4 [range 2-7]), fertilization rate (62.4% vs. 57.0%), biochemical pregnancy rate (20.5% vs. 22.9%), clinical pregnancy rate (16.4% vs. 18.3%), and implantation rate (29.8% vs. 30.4%) between the 450 IU and 600 IU groups, respectively. CONCLUSION(S): Gonadotropin of 600 IU/d does not improve outcome of IVF cycles compared with 450 IU/d in women at risk of poor ovarian response. CLINICAL TRIAL REGISTRATION NUMBER: NCT00971152.


Subject(s)
Fertility Agents, Female/administration & dosage , Follicle Stimulating Hormone/administration & dosage , Infertility/therapy , Menotropins/administration & dosage , Ovary/drug effects , Ovulation Induction/methods , Ovulation/drug effects , Urofollitropin/administration & dosage , Adult , Embryo Implantation , Embryo Transfer , Female , Fertility Agents, Female/adverse effects , Fertilization in Vitro , Follicle Stimulating Hormone/adverse effects , Humans , Infertility/diagnosis , Infertility/physiopathology , Menotropins/adverse effects , Oocyte Retrieval , Ovary/physiopathology , Ovulation Induction/adverse effects , Pregnancy , Pregnancy Rate , Prospective Studies , Quebec , Sperm Injections, Intracytoplasmic , Treatment Outcome , Urofollitropin/adverse effects
6.
J Obstet Gynaecol Can ; 33(12): 1248-52, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22166279

ABSTRACT

OBJECTIVE: Intrauterine insemination (IUI) is a commonly used treatment for infertility. Optimal timing of insemination is achieved either by ultrasound monitoring of follicular growth followed by the administration of human chorionic gonadotropin (hCG) or by the detection of a luteinizing hormone (LH) surge through urinary LH testing (uLH). However, in cycles where follicular growth is monitored, there is a possibility of a premature LH rise which may affect the outcome of treatment. The objective of the current study was to determine the frequency of spontaneous LH surges in ultrasound-monitored IUI cycles. METHODS: One hundred IUI cycles were followed for this prospective cohort study. In combination with ultrasound monitoring, uLH testing was performed twice daily. A serum LH test was performed in the case of an inconclusive uLH test result. IUI was performed either on the day after a positive LH test or, if the diameter of the dominant follicle reached 18 mm and the LH test was still negative, 36 hours after ovulation triggering by administration of hCG. RESULTS: Of the 87 analyzed cycles, 19 (21.8%) exhibited a premature LH surge as detected by urine testing. Eleven further cycles had an inconclusive urine result, and in six of these (6.9% of cycles) the result was confirmed positive by serum LH testing, giving a total of 25 cycles (28.7%) experiencing a premature LH surge. CONCLUSION: A considerable proportion of patients undergoing ultrasound-monitored IUI cycle had a spontaneous LH surge before ovulation triggering was scheduled. This could affect pregnancy rates following IUI.


Subject(s)
Algorithms , Infertility/therapy , Insemination, Artificial/methods , Luteinizing Hormone/urine , Ovarian Follicle/diagnostic imaging , Chorionic Gonadotropin/administration & dosage , Cohort Studies , Female , Humans , Luteinizing Hormone/blood , Male , Ovulation Induction , Pregnancy , Prospective Studies , Time Factors , Ultrasonography
7.
Fertil Steril ; 90(3): 546-50, 2008 Sep.
Article in English | MEDLINE | ID: mdl-17904128

ABSTRACT

OBJECTIVE: To compare rates of pregnancy loss after oocyte maturation in vitro (IVM), after IVF, and after intracytoplasmic sperm injection (ICSI). DESIGN: Retrospective comparative study. SETTING: University tertiary-care center for infertility. PATIENT(S): Women undergoing assisted reproductive technology in a single center. INTERVENTION(S): Oocyte maturation in vitro, IVF, or ICSI, as indicated. MAIN OUTCOME MEASURE(S): Biochemical pregnancy, clinical miscarriage, ectopic pregnancy, and late fetal loss. RESULT(S): There were 1,581 positive pregnancy tests (120 IVM, 849 IVF, and 612 ICSI). The biochemical pregnancy loss rate did not statistically significantly differ among the groups: 17.5% (21/120) after IVM, 17.0% (144/849) after IVF, and 18.0% (110/612) after ICSI. The clinical miscarriage rate after IVM was 25.3% (25/99), which was statistically significantly different compared with 15.7% (111/705) after IVF and 12.6% (63/502) after ICSI. However, the clinical miscarriage rates in women with polycystic ovary syndrome were statistically similar, at 24.5% (24/98) after IVM and 22.2% (18/81) after IVF. The ectopic pregnancy rates also were statistically similar: 1.0% (1/99) after IVM, 2.3% (16/705) after IVF, and 1.8% (9/502) after ICSI. The late fetal loss rates were similar as well: 1.0% (1/99) after IVM, 2.7% (19/705) after IVF, and 2.9% (14/502) after ICSI. There were no chromosomal abnormalities in the IVM group. CONCLUSION(S): There is a higher rate of clinical miscarriage after IVM when compared with IVF and ICSI. This appears to be related to polycystic ovary syndrome rather than to the IVM procedure.


Subject(s)
Abortion, Spontaneous/epidemiology , Fertilization in Vitro/statistics & numerical data , Infertility/epidemiology , Infertility/therapy , Risk Assessment/methods , Sperm Injections, Intracytoplasmic/statistics & numerical data , Adult , Female , Humans , Incidence , Pregnancy , Quebec/epidemiology , Retrospective Studies , Risk Factors , Treatment Outcome
8.
Fertil Steril ; 86(1): 98-105, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16716318

ABSTRACT

OBJECTIVE: To elucidate the timing and variability of CTG repeat expansion within the human dystrophia myotonica protein kinase (DMPK) gene in early development. DESIGN: Triplet-primed polymerase chain reaction was used to amplify the expanded CTG repeat in oocytes and embryos obtained from myotonic dystrophy 1 (DM1) patients, and a heminested polymerase chain reaction approach was used to amplify the normal CTG repeats in supernumerary IVF embryos. SETTING: University hospital laboratory. PATIENT(S): Two DM1-affected females undergoing preimplantation genetic diagnosis who carried different CTG repeats. Also, 61 IVF patients who carried a (CTG)(5-18) and (CTG)(19-37) normal DMPK repeat. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The degree of expansion of the repeat in the oocytes and embryos compared with the DM1-affected maternal repeat and the size of the (CTG)(19-37) repeat compared with the parental size in IVF embryos. RESULT(S): The degree of repeat expansion was greater than the DM1 maternal lymphocyte for two of four oocytes, including a germinal vesicle-stage oocyte and 17 of 20 three-cell to blastocyst stage embryos. A change in the (CTG)(19-37) repeat was seen in 7 (7%) of 95 paternal transmissions but in no maternal transmissions. CONCLUSION(S): Because the repeat was already expanded in the immature oocyte, the initial expansion most likely occurs during oogenesis. A variable degree of DMPK(CTG)(n) expansion in the embryo is seen from different mothers. In addition, instability in paternal transmission of normal-range (CTG)(19-37) repeats occurs at the level of the embryo.


Subject(s)
Blastocyst/physiology , Muscular Dystrophies/congenital , Muscular Dystrophies/genetics , Oocytes/physiology , Protein Serine-Threonine Kinases/genetics , Trinucleotide Repeat Expansion/genetics , Adult , Cells, Cultured , Chromosome Mapping , DNA Mutational Analysis , Female , Genetic Predisposition to Disease/genetics , Genetic Variation/genetics , Genomic Instability/genetics , Humans , Myotonin-Protein Kinase , Pregnancy , Prenatal Diagnosis
9.
Eur J Hum Genet ; 14(3): 299-306, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16391559

ABSTRACT

One form of myotonic dystrophy, dystrophia myotonica 1 (DM1), is caused by the expansion of a (CTG)(n) repeat within the dystrophia myotonica-protein kinase (DMPK) gene located in chromosome region 19q13.3. Unaffected individuals carry alleles with repeat size (CTG)(5-37), premutation carriers (CTG)(38-49) and DM1 affected individuals (CTG)(50-6,000). Preferential transmission both of expanded repeats from DM1-affected parents and larger DMPK alleles in the normal-size range have been reported in live-born offspring. To determine the moment in development when transmission ratio distortion (TRD) for larger normal-size DMPK alleles is generated, the transmission from heterozygous parents with one repeat within the (CTG)(5-18) range (Group I repeat) and the other within the (CTG)(19-37) range (Group II repeat) to human preimplantation embryos was analysed. A statistically significant TRD of 59% (95% confidence interval of 54-64) in favour of Group II repeats from both mothers and fathers was observed in preimplantation embryos, which remained significant when female embryos were considered separately. In contrast, no significant TRD was detected for repeats from informative Group I/Group I parents. Our analysis showed that Group II repeats specifically were preferentially transmitted in human preimplantation embryos. We suggest that TRD, in Group II repeats at the DMPK locus, is likely to result from events occurring at or around the time of fertilisation.


Subject(s)
Blastocyst , Mutation , Myotonic Dystrophy/genetics , Alleles , Chromosome Mapping , Chromosomes, Human, Pair 19 , Embryo, Mammalian/metabolism , Fathers , Female , Fertilization , Fertilization in Vitro , Gene Frequency , Genotype , Heterozygote , Humans , Male , Mothers , Myotonin-Protein Kinase , Protein Serine-Threonine Kinases/genetics , Repetitive Sequences, Nucleic Acid , Spermatozoa/metabolism , Trinucleotide Repeat Expansion
10.
Mol Hum Reprod ; 9(10): 631-8, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12970401

ABSTRACT

To perform preimplantation genetic diagnosis for women carrying heteroplasmic mitochondrial DNA (mtDNA) mutations, it is necessary to ensure that the proportion of mutant mtDNA diagnosed in the biopsied cell gives an accurate indication of the mutant load in the remaining embryo. A heteroplasmic mouse model, carrying NZB and BALB mtDNA genotypes, was used to study the relative proportions of each mtDNA genotype in the ooplasm and first polar body of mature oocytes, and between blastomeres of early cleavage stage embryos. The levels of heteroplasmy varied widely in the gametes compared with the maternal genotype. However, the distribution of the two mtDNA genotypes was virtually identical between the ooplasm and polar body of a mature oocyte, and also between the blastomeres of each 2-, 4- and 6-8-cell embryo. Therefore, the level of heteroplasmy diagnosed from the polar body of an unfertilized oocyte or from a single blastomere of an embryo is representative of the level in the embryo as a whole. Reliable results were obtained from both polar bodies and blastomeres, but the efficiency of diagnosis was greater with blastomeres. We conclude that preimplantation genetic diagnosis is feasible for mtDNA diseases, although it should be approached with caution, as it is possible that transmission of some pathogenic mutations could behave in a different manner.


Subject(s)
DNA, Mitochondrial/genetics , Mitochondrial Diseases/congenital , Mitochondrial Diseases/genetics , Preimplantation Diagnosis/methods , Animals , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Female , Genotype , Mice , Oocytes/cytology , Oocytes/metabolism , Polymerase Chain Reaction , Pregnancy
11.
J Assist Reprod Genet ; 20(11): 461-4, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14714825

ABSTRACT

PURPOSE: To investigate whether the consecutive embryo transfer of day 3 embryos and of blastocyst protects against failure to reach embryo transfer and provides additional pregnancies. METHODS: An embryo transfer was performed on day 3 following which all remaining embryos were cultured to the blastocyst stage for a possible second transfer. RESULTS: One hundred and forty-two patients were selected for extended culture. Thirty-two of these patients did not develop blastocysts in culture, however, there were 12 pregnancies achieved in this group. CONCLUSIONS: The consecutive transfer of day 3 embryos and blastocysts can prevent the total loss of a cycle when embryos fail to develop to the blastocyst stage in culture and thereby provide additional pregnancies.


Subject(s)
Blastocyst/physiology , Embryo Implantation , Embryo Transfer , Embryo, Mammalian/cytology , Pregnancy/physiology , Adult , Culture Techniques , Embryo, Mammalian/physiology , Female , Fertilization in Vitro , Humans , Male , Pregnancy Rate
12.
Expert Rev Neurother ; 2(4): 561-72, 2002 Jul.
Article in English | MEDLINE | ID: mdl-19810954

ABSTRACT

This review examines the history, present status and future of genetic antenatal diagnosis for the trinucleotide repeat disorders, including Huntington's disease, Fragile X syndrome and myotonic dystrophy. Conventional prenatal diagnosis and the relatively new field of preimplantation genetic diagnosis, which can diagnose an affected embryo before a pregnancy is established, are described. Genetic diagnosis for these late onset diseases has inherent difficulties and many controversies. However, antenatal diagnosis is an important service for an individual with one of these mutations, who wishes to prevent the birth of an affected child.

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