Correction of disease-causing mutations in human embryos holds the potential to reduce the burden of inherited genetic disorders and improve fertility treatments for couples with disease-causing ...mutations in lieu of embryo selection. Here, we evaluate repair outcomes of a Cas9-induced double-strand break (DSB) introduced on the paternal chromosome at the EYS locus, which carries a frameshift mutation causing blindness. We show that the most common repair outcome is microhomology-mediated end joining, which occurs during the first cell cycle in the zygote, leading to embryos with non-mosaic restoration of the reading frame. Notably, about half of the breaks remain unrepaired, resulting in an undetectable paternal allele and, after mitosis, loss of one or both chromosomal arms. Correspondingly, Cas9 off-target cleavage results in chromosomal losses and hemizygous indels because of cleavage of both alleles. These results demonstrate the ability to manipulate chromosome content and reveal significant challenges for mutation correction in human embryos.
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•Cas9-mediated DSB induction and repair by end joining occurs within hours•End joining provides an efficient way to restore reading frames without mosaicism•Unrepaired DSBs persist through mitosis and result in frequent chromosome loss•Off-target effects of Cas9 cause indels as well as chromosome loss
CRISPR-Cas9 gene editing in early human embryos leads to frequent loss of the targeted chromosome, indicating that human germline gene editing would pose a substantial risk for aneuploidy and other adverse genetic consequences
Human cleavage-stage embryos frequently acquire chromosomal aneuploidies during mitosis due to unknown mechanisms. Here, we show that S phase at the 1-cell stage shows replication fork stalling, low ...fork speed, and DNA synthesis extending into G2 phase. DNA damage foci consistent with collapsed replication forks, DSBs, and incomplete replication form in G2 in an ATR- and MRE11-dependent manner, followed by spontaneous chromosome breakage and segmental aneuploidies. Entry into mitosis with incomplete replication results in chromosome breakage, whole and segmental chromosome errors, micronucleation, chromosome fragmentation, and poor embryo quality. Sites of spontaneous chromosome breakage are concordant with sites of DNA synthesis in G2 phase, locating to gene-poor regions with long neural genes, which are transcriptionally silent at this stage of development. Thus, DNA replication stress in mammalian preimplantation embryos predisposes gene-poor regions to fragility, and in particular in the human embryo, to the formation of aneuploidies, impairing developmental potential.
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•1-cell embryos show replication fork stalling, with replication extending into G2 phase•Incompletely replicated DNA is converted to chromosome breaks and aneuploidy in mitosis•Spontaneous chromosome breaks and G2 DNA synthesis occur in congruent gene-poor regions•Chromosome fragility in human embryos occurs independently of embryonic genome activation
In human preimplantation embryos, DNA replication in G2 phase results in chromosome breakage, segmental aneuploidies, and poor embryo quality.
Purpose
Advances in preimplantation genetic testing (PGT) have led to practice changes in assisted reproductive technologies (ART), enabling fertility centers to transfer single embryos while ...maintaining excellent ongoing pregnancy rates, reducing miscarriage rates, and dramatically reducing ART-associated multiple pregnancies. The introduction of next-generation sequencing (NGS) allows PGT laboratories to assess for embryo mosaicism—although the true incidence and reproductive potential of predicted mosaic embryos are controversial. Due to concern for genetic contamination from other spermatozoa, most reference laboratories require use of intracytoplasmic sperm injection (ICSI) for single gene preimplantation genetic diagnosis (PGT-M). However, in PGT for aneuploidy (PGT-A), conventional insemination (IVF) is typically permissible. The purpose of this study was to evaluate rates of euploid, aneuploid, and mosaic in trophectoderm biopsy samples from embryos in IVF versus ICSI PGT-A cycles. Secondary aims were to assess sex ratio, and subtypes of aneuploidy and mosaicism in IVF versus ICSI PGT-A cycles.
Methods
We performed a retrospective review of women undergoing PGT-A at a single academic fertility center from July 1, 2015, to September 1, 2017. In all cycles, PGT-A was performed via trophectoderm biopsy on day 5 or 6 and analyzed using NGS at a single reference lab. We collected and compared patient demographics, fertility testing, cycle characteristics, and PGT-A outcomes between IVF and ICSI cycles.
Results
Three hundred two PGT-A cycles were included for analysis: 75 IVF and 227 ICSI cycles, resulting in 251 IVF and 724 ICSI biopsied blastocysts. Mean oocyte age of included cycles was 38.6 years (IVF) and 38.5 years (ICSI),
p
= 0.85. Baseline characteristics of IVF and ICSI PGT-A cycles were similar with the exception of semen parameters: IVF cycles had higher sperm concentration and total motility compared to ICSI cycles. PGT-A outcomes did not differ between IVF and ICSI cycles: euploid 27.9% (IVF) versus 30% (ICSI); aneuploid 45.4% (IVF) versus 43.1% (ICSI); no result 4.4% (IVF) versus 6.2% (ICSI). Though not significant, we identified a trend toward higher rate of mosaicism in IVF (25.9%) versus ICSI (20.9%). Among mosaic embryos, a lower percentage of simple mosaic embryos resulted from IVF (53.8%) versus ICSI (70.2%). Among aneuploid embryos, a non-significant higher percentage of complex aneuploidy resulted from IVF (16.3%) versus ICSI (9%). IVF resulted in a non-significant higher proportion of cycles with no transferrable embryos (42.7%) versus ICSI (36.6%). Numerical and sex chromosome involvement in mosaicism and aneuploidy were similar between IVF and ICSI cycles.
Conclusion
IVF and ICSI NGS PGT-A have similar rates of euploid, aneuploid, and no result embryos, though IVF may result in higher rates of mosaicism and demonstrates differences in proportions of mosaic and aneuploid subtypes compared to ICSI. ICSI may be preferable to conventional insemination to minimize the rate of mosaic results in NGS PGT-A cycles.
Ovarian hyperstimulation syndrome is a potentially life-threatening clinical condition.
The objective of this study was to evaluate risk factors for life-threatening complications for patients with ...severe ovarian hyperstimulation syndrome in a United States nationwide sample.
Ovarian hyperstimulation syndrome admissions from 2002 to 2011 from the Nationwide Inpatient Sample were included in this study. The association between patient and hospital factors and life-threatening complications (deep vein thrombosis/pulmonary embolism, acute respiratory distress syndrome, acute renal failure, intubation), nonroutine discharge (discharge to skilled nursing facility, transfer hospital), prolonged length of stay, and total hospital charges were analyzed. Survey-adjusted multivariable logistic regression analyses were performed for these outcomes, controlling for risk factors, with adjusted odds ratios with 95% confidence intervals as the measures of effect.
A total of 11,562 patients were hospitalized with severe ovarian hyperstimulation syndrome from 2002 to 2011. The majority were white (55.7%), with private insurance (87.7%), aged 25–39 years (84.6%), and hospitalized in an urban location (95%). In all, 19.3% of patients had medical comorbidities including hypertension, diabetes, obesity, hypothyroidism, and anemia. Life-threatening complications occurred in 4.4% of patients (deep vein thrombosis/pulmonary embolism, 2.2%; acute renal failure; acute respiratory distress syndrome, 0.9%; intubation, 0.5%). Patients ≥40 years old (odds ratio, 4.02; 95% confidence interval, 1.37, 11.76), those with comorbidities (odds ratio, 2.29; 95% confidence interval, 1.46, 3.57), and African American patients (odds ratio, 2.15; 95% confidence interval, 1.25, 3.70) were more likely to develop life-threatening conditions. Patients with medical comorbidities (odds ratio, 0.39; 95% confidence interval, 0.24, 0.63) were also less likely to be routinely discharged from the hospital. Adjusting for patient and hospital demographics, patients with comorbidities were more likely to develop deep vein thrombosis/pulmonary embolism (adjusted odds ratio, 2.44; 95% confidence interval, 1.28, 4.65) and acute renal failure (adjusted odds ratio, 2.26; 95% confidence interval, 1.21, 4.23). Patients who developed life-threatening complications had longer hospital length of stay (adjusted odds ratio, 3.72; 95% confidence interval, 2.28, 6.07) and higher hospital costs (adjusted odds ratio, 5.20; 95% confidence interval, 3.22,8.39).
Patients with common medical comorbidities are at higher risk for life-threatening complications in the setting of severe ovarian hyperstimulation syndrome. Furthermore, these complications are associated with high hospital costs and hospital burden. Given the increasing number of in vitro fertilization patients with medical comorbidities, closer monitoring of at-risk patients may be indicated. As assisted reproductive technology practice changes in recent years with strategies designed to reduce ovarian hyperstimulation syndrome risk, future studies are needed to assess the impact of these changes on hospitalization and complication risk.
The objective of the study was to determine the rates and predictors of fertility preservation services among reproductive-aged women with common cancers in the United States.
We used the MarketScan ...database to identify women 18–45 years of age with lung, breast, colorectal, or cervical cancer who underwent surgery and chemotherapy from 2009 through 2016. Services from 3 months before to 3 months after chemotherapy for evaluation for fertility preservation, laboratory testing for fertility evaluation, and fertility-preserving procedures were captured. Multivariable models were used to assess the factors associated with the use of fertility-preservation services.
A total of 18,781 women, including 386 cervical, 1372 colorectal, 246 lung, and 16,777 with breast cancer, were identified. In women 18–35 years old, 11.7% underwent evaluation for fertility preservation, 13.7% underwent laboratory testing, and 6.3% pursued fertility-preserving procedures. The rates of office evaluation, laboratory testing, and performance of procedure were 3.3%, 7.5%, and 1.9 % in women aged 36–40 years and 0.5%, 7.2%, and 0.3% in those aged 41–45 years, respectively. The rate of fertility preservation evaluation rose from 1.0% in 2009 to 5.5% in 2016 (risk ratio, 4.66, 95% confidence interval, 2.38–9.11) while use of fertility-preserving procedures increased from 1.0% to 4.6% (risk ratio, 3.84, 95% confidence interval, 1.94–7.59) during the same time period. In a multivariable model, use of any fertility-preserving interventions were more common in patients with breast cancer (adjusted risk ratio, 2.30, 95% confidence interval, 1.30–4.06), those in the Northeast (adjusted risk ratio, 1.24, 95% confidence interval, 1.10–1.40), and in younger women (18–35 years) (adjusted risk ratio, 2.59, 95% confidence interval, 2.32–2.89).
Although limited by lack of information regarding cancer stage and desire for future fertility, only a small fraction of reproductive-aged female cancer patients receiving chemotherapy are evaluated in a nationwide sample for fertility preservation or undergo fertility-preserving procedures.
Purpose
To examine the effect of low and very low estradiol responses in oocyte donors receiving gonadotropins on clinical outcomes of donor in vitro fertilization (IVF) cycles and to identify ...possible mechanisms responsible for low estradiol response.
Methods
This is a retrospective cohort study of oocyte donors undergoing antagonist IVF cycles with progression to oocyte retrieval between January 2010 and December 2016 at a single urban academic fertility center. Oocyte yield, fertilization rate, blastocyst rate, percentage of normal embryos on preimplantation genetic screening (PGS), pregnancy outcomes, and follicular fluid steroid profiles were compared between donors with normal estradiol response and those with low estradiol response.
Results
Three hundred sixty-six antagonist oocyte donor IVF cycles were identified: 42 cycles had a normal estradiol response (NE2), defined as peak serum estradiol (E2) of over 200 pg/mL per retrieved oocyte; 140 cycles had an intermediate estradiol response (iE2), defined as peak serum E2 between 100 and 200 pg/mL per retrieved oocyte; 110 cycles had a low estradiol response (LE2), defined as peak serum E2 between 50 and 100 pg/mL per retrieved oocyte; and 74 cycles had a very low estradiol response (vLE2), defined as peak serum E2 less than 50 pg/mL per retrieved oocyte. LE2 cycles resulted in a greater number of mature oocytes (22.4 vs. 13.6,
p
< 0.017), and fertilizations versus NE2 donors (18.5 vs. 10.7,
p
< 0.017), although the number of transferred or cryopreserved blastocysts were similar between groups (8.6, 6.9 vs. 4.8,
p
= 0.095,
p
= 1). The percentage of chromosomally normal embryos after PGS was similar between LE2, vLE2, and NE2 cycles (66.4, 71.8 vs. 63.1%,
p
= 0.99,
p
= 1). Pregnancy outcomes were similar between LE2, vLE2, and NE2 cycles. Serum AMH obtained on the day of peak E2 was similar to baseline serum AMH and did not differ between LE2 versus NE2 cycles. Follicular fluid E2 levels paralleled serum E2 levels and were lower in LE2 cycles versus NE2 cycles.
Conclusion
The prevalence of very low E2 responses in donors appears to be high (20.2%). In contrast to autologous IVF cycles, LE2 does not portend poor outcomes in oocyte donors.
To study the beneficial effects of thyroid replacement therapy (TRT) on pregnancy outcomes in patients with subclinical hypothyroidism (SCl hypoT) with respect to thyroid peroxidase (TPO) ...autoantibodies.
Retrospective study of 706 patients.
Not applicable.
The study evaluated 706 patients, who were divided into 3 cohorts: euthyroid patients, with pre–in vitro fertilization thyroid-stimulating hormone levels of <2.5 μIU/mL; patients with SCl hypoT, defined as thyroid-stimulating hormone levels of >2.5 μIU/mL and <4 μIU/mL, who were not treated; and patients with SCl hypoT who received TRT. The 3 cohorts were further subclassified into 2 groups, each based on TPO antibody levels.
The cohorts were compared for the effects of TRT on pregnancy outcomes.
Identification of effects of TRT on assisted reproductive technology outcomes.
Patients with SCl hypoT had significantly fewer positive pregnancy outcomes than euthyroid patients. Importantly, low-dose TRT was found to be beneficial in improving IVF success and pregnancy outcomes in patients with SCl hypoT. The original cohort of patients, further classified into 2 subgroups on the basis of antithyroid (TPO) antibodies, showed that low-dose TRT was associated with improved pregnancy outcomes in women with SCl hypoT and TPO-positive antibodies.
Our findings demonstrate that low-dose TRT may be beneficial in improving in vitro fertilization success and pregnancy outcomes in women with SCl hypoT and TPO-positive antibodies.
Objective: Universal perioperative mechanical thromboprophylaxis is recommended for patients undergoing cesarean delivery because of increased risk for venous thromboembolism (VTE) associated with ...this mode of delivery. While research supports clinical benefits from this approach, other specialties have demonstrated suboptimal compliance with prophylaxis device use. The objective of this study was to review patient compliance with sequential compression devices (SCDs).
Methods: This cross-sectional observational study utilized data from a prospective quality assurance analysis to evaluate demographic, medical and obstetrical factors associated with postoperative SCD compliance after cesarean delivery. Observations were performed before 7 a.m. on the first postoperative day, a time point when patients were unlikely to be fully ambulatory and would most benefit from device use. The reason for failure was documented in cases where the device was not being properly used.
Results: Two hundred and ninety-three patients underwent cesarean delivery, had SCD compliance assessed and were included in the analysis. Twenty one percent of patients (n=60) were non-compliant with SCD use. Reasons for noncompliance included patient discomfort, machine malfunction and incorrect device use. Patients who were non-compliant had similar risk factors for thromboembolism compared to women who were compliant.
Conclusion: Although SCD's are effective in preventing thromboembolism, device use was suboptimal in this cohort of post-cesarean patients. These findings are similar to those from other fields. For institutions that rely primarily on mechanical thromboprophylaxis for obstetric patients, quality assurance and auditing of use may be necessary to ensure patients are receiving adequate prophylaxis. For post-cesarean patients with additional VTE risk factors, pharmacologic prophylaxis may be beneficial.
Abstract Background The prevalence of morbidly adherent placenta has dramatically increased in the setting of the rising cesarean rate in the United States. Delayed surgical management of placenta ...accreta and its variants
is
emerging as methods that may significantly decrease bleeding and perioperative complications; however, optimal surgical approaches have not yet been determined. In this report, we present a case of robotic-assisted delayed interval hysterectomy in a patient with placenta percreta. Method A minimally invasive approach, via a robotic-assisted total laparoscopic hysterectomy, was utilized for a 39-year-old gravida 9 para 3 with placenta percreta with placenta left in situ ten weeks after a tertiary cesarean section. Experience The robotic approach provided excellent visualization to facilitate fine planes of dissection, lower than expected estimated blood loss, and faster recover times when compared with conventional surgical approaches traditionally utilized for interval hysterectomies for placenta percreta. Conclusion Robotic-assisted hysterectomy may be considered as an alternative to laparotomy for the delayed interval surgical management of morbidly adherent placenta percreta.
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