IVF outcomes pre- and post-anti-COVID-19 vaccination - Are there any differences?

Since the beginning of the SARS-CoV-2 pandemic, there have been rising concerns about the virus's possible ability to affect male and female fertility. Although effective vaccines were introduced and the vaccination rate of the general population is high, some reproductive-age individuals are still hesitant to receive the vaccine, because of an unestablished belief that the vaccine might impair fertility. In this single-center retrospective study, encompassing data from 387 medical files of in-vitro fertilization (IVF) patients we compared IVF cycle outcomes and sperm characteristics in vaccinated couples before and after vaccination, as well as between vaccinated patients and a control group of individuals who were neither vaccinated nor infected with COVID-19 before or during the cycles. We found no significant differences between vaccinated and non-vaccinated patients concerning the number of retrieved oocytes and the total motile sperm count (TMC). The mean number of retrieved oocytes showed a slight increase in the vaccinated group compared to the non-vaccinated control group (10.8 vs. 9.18, p = 0.14). Additionally, within the vaccinated group, no significant difference was observed in the mean number of oocytes before and after vaccination (9.7 and 10.8, p = 0.14). Other similar cycle outcomes between the groups were the rates of implantation, pregnancy, and ovarian hyperstimulation syndrome. This study emphasized that the mRNA anti-COVID-19 vaccination doesn't adversely affect ovarian response or sperm quality in IVF patients. These findings contribute valuable insights to the safety profile of anti-COVID-19 vaccines in the context of reproductive-aged populations, aiding decision-making during ongoing virus outbreaks and potential future scenarios.

Impact of pre-treatment in GnRH-antagonist cycles triggered with GnRH agonist on reproductive outcomes.

OBJECTIVE: Pre-treatment (PT) therapies in IVF are known to be used as pre-stimulation modality to improve cycle outcomes. This study aims to assess whether PT in GnRH antagonist cycles triggered with GnRH-agonist impact oocyte maturation response. METHODS: Data were retrospectively collected for patients who underwent GnRH antagonist cycle with agonist triggering with and without PT. The patients were allocated to groups according to their PT status. The primary outcome evaluated was suboptimal maturation response. Suboptimal maturation to trigger was defined as no oocyte upon retrieval when adequate response was expected. RESULTS: The study population included 196 patients who underwent GnRH antagonist cycle with agonist triggering. The study group included 69 patients who received PT. The control group included 127 patients with no PT. In univariate analysis, the PT group significantly displayed suboptimal response compared to the controls (p = 0.008). All the patients in the study group with suboptimal response (with or without hCG re-triggering) were treated with GnRH-agonist as PT. Basal and pre-trigger LH values were significantly lower in the study group compared to controls (p < 0.001). Multivariate regression analysis revealed that PT with GnRH agonist was a significant predictor for suboptimal response. CONCLUSIONS: Pre-treatment, and particularly the use of GnRH-agonist as PT in antagonist cycles triggered with agonist, increases the risk of suboptimal response to GnRH-agonist trigger. This might be explained by prolonged pituitary suppression, which lasts beyond the PT cessation.

The importance of gynecological examination in adolescent girls and adult women with Prader-Willi syndrome.

Current published guidelines for routine care of women with Prader-Willi syndrome (PWS) do not include recommendations for gynecologic examinations. We describe our experience with gynecological examinations in women with PWS and offer recommendations for routine health care for these patients. Data were collected on all 41 PWS females ages ≥12 year, followed in our national Israeli multidisciplinary clinic between the years 2011 and 2022. Menstrual data and findings on external gynecological examination, including evaluation of the vulva and hymen were recorded at yearly visits. During the gynecological evaluation the topic of sexual education was discussed. Pelvic ultrasound, specifically for antral follicular count, was performed for those visiting the clinic during 2020-2022. Blood samples for luteinizing hormone (LH), follicular stimulating hormone (FSH), and estradiol were obtained routinely and DEXA scans for bone density were done when indicated. Of the 41 women, (median age at start of follow-up 17 years, range [12.3-39], BMI 30.4 kg/m2 [IQR 23.5-37.1]), 39 women agreed to external gynecological examination. Eleven women (27%) had spontaneous menses, with menarche at the age of 14 to as late as 31 years. The hymen was intact in all except one. Poor hygiene was observed in eight women, three women with vulvovaginitis, and five with irritated vulva related to poor hygiene. Gynecological ultrasound was performed in 27 women. In 22, endometrial thickness was less than 5 mm. The median antral follicular count (AFC) was 6 (<10th percentile for age). No correlation between AFC and menstruation or BMI was found. Mean FSH level was 5.7 ± 3.6 IU, LH was 2.29 ± 2.23, and estradiol was 128 ± 76 pmol/L. Data on DEXA measurements were available in 25 women aged 16-39. Median spine T score was -1.3 (range between 0.5 and -3.7), and hip T score was -1.2 (range between 0.8 and -3.3). A negative correlation was found between endometrial thickness and the presence of osteopenia or osteoporosis (r = -0.5, p = 0.013). Despite our recommendations, only eight of 14 women agreed to hormonal treatment or contraception. One woman who received treatment had a thromboembolic event. Routine health care for women with PWS should include gynecological examinations. The gynecological evaluation should include external genital examination, assessment of hygiene, obtaining a blood sample for hormone levels, and documenting a history of sexual experience or sexual abuse. Hormonal treatment or contraception should be offered when appropriate.

Differentiation of uniparental human embryonic stem cells into granulosa cells reveals a paternal contribution to gonadal development.

Genomic imprinting underlies the mammalian requirement for sexual reproduction. Nonetheless, the relative contribution of the two parental genomes during human development is not fully understood. Specifically, a fascinating question is whether the formation of the gonad, which holds the ability to reproduce, depends on equal contribution from both parental genomes. Here, we differentiated androgenetic and parthenogenetic human pluripotent stem cells (hPSCs) into ovarian granulosa-like cells (GLCs). We show that in contrast to biparental and androgenetic cells, parthenogenetic hPSCs present a reduced capacity to differentiate into GLCs. We further identify the paternally expressed gene IGF2 as the most upregulated imprinted gene upon differentiation. Remarkably, while IGF2 knockout androgenetic cells fail to differentiate into GLCs, the differentiation of parthenogenetic cells supplemented with IGF2 is partly rescued. Thus, our findings unravel a surprising essentiality of genes that are only expressed from the paternal genome to the development of the female reproductive system.

PGT pregnancies have a similar risk for post-partum complications as naturally conceived pregnancies.

RESEARCH QUESTION: Do preimplantation genetic testing (PGT) pregnancies have higher post-partum complications compared with naturally conceived pregnancies? DESIGN: Retrospective cohort study conducted in 2008-2020 at the Shaare Zedek Medical Center (SZMC), including all patients aged 18-45 years old who conceived following PGT with a singleton live birth >24 weeks. Data were collected from computerized hospital databases and patient files. There were two control groups: (i) pregnancies following IVF-ICSI (intracytoplasmic sperm injection); (ii) four neighbourhood controls for each case delivery (two women delivered before and two after) of women with naturally conceived pregnancies. RESULTS: Overall, 120 PGT, 779 IVF-ICSI and 3507 naturally conceived deliveries were included. Demographic variables were similar apart from slightly higher age in the PGT (P = 0.003) and ICSI (P = 0.002) groups (31.07 ± 4.38 PGT, 31.66 ± 5.03 ICSI, 28.77 ± 5.72 naturally conceived). Composite post-partum placental-related complications (manual lysis of placenta, revision of uterine cavity, haemoglobin drop ≥3 g/dl, post-partum haemorrhage, need for blood transfusion) were more prevalent in both the PGT and IVF-ICSI groups as opposed to naturally conceived (20.0% versus 18.9% versus 10.3%, respectively, P < 0.001, P = 0.007). In a multivariate regression model PGT was not found to be independently associated with composite post-partum placental-related complications (adjusted odds ratio [aOR] 1.44, 95% confidence interval [CI] 0.83-2.15), while IVF-ICSI pregnancies had increased risk (aOR 1.52, 95% CI 1.20-1.97) compared with natural conception. No difference was found between fresh and frozen cycles or between day 3 and day 5 embryo transfer. CONCLUSIONS: PGT pregnancies have a comparable risk of post-partum placental-related complications to naturally conceived pregnancies, unlike IVF-ICSI pregnancies. It is possible that infertility itself is the main mediator for post-partum complications in IVF-ICSI pregnancies.

Clinical outcome of planned oocyte cryopreservation at advanced age.

PURPOSE: To report outcome of planned oocyte cryopreservation (POC) in the first 8 years of this treatment in our center. METHODS: A retrospective study in a university-affiliated medical center. RESULTS: A total of 446 women underwent POC during 2011-2018. Fifty-seven (13%) women presented to use these oocytes during the study period (until June 2021). POC was performed at a mean age of 37.9 ± 2.0 (range 33-41). Age at thawing was 43.3 ± 2.1 (range 38-49). A total of 34 (60%) women transferred their oocytes for thawing at other units. Oocyte survival after thawing was significantly higher at our center than following shipping to ancillary sites (78 vs. 63%, p = 0.047). Forty-nine women completed their treatment, either depleting their cryopreserved oocytes without conceiving (36) or attaining a live birth (13)-27% live birth rate per woman. Only one of eleven women who cryopreserved oocytes aged 40 and older had a live birth using thawed oocytes. CONCLUSION: Women should be advised to complete planned oocyte cryopreservation before age 40, given low success rates in women who underwent cryopreservation at advanced reproductive age. In this study, oocyte shipping was associated with lower survival rate. These findings may be relevant for women considering POC and utilization of cryopreserved oocytes.

Extended fertility at highly advanced reproductive age is not related to anti-Müllerian hormone concentrations.

RESEARCH QUESTION: Is extended fertility at the advanced reproductive age of 43-47 years associated with high anti-Müllerian hormone (AMH) concentrations? DESIGN: Prospective cohort study including 98 women aged 43-47 years old with a spontaneous conception who were tested for AMH concentrations 1-4 days and 3-11 months post-partum. AMH concentrations at 3-11 months post-partum were further compared with AMH concentrations in healthy age-matched controls that last gave birth at ≤42 years old. Women with current use of combined hormonal contraceptives (CHC), ovarian insult or polycystic ovary syndrome were excluded. Power analysis supported the number of participating women. RESULTS: Median AMH concentrations did not differ between the extended fertility (n = 40) and control (n = 58) groups (0.50 versus 0.45 ng/ml, P = 0.51). This remained when analysing by age (≥ or <45 years old). AMH concentrations and women's age did not correlate within the extended fertility group (r = 0.017, P = 0.92); a weak negative correlation was found within the control group (r = -0.23, P = 0.08). AMH was significantly higher 3-11 months post-partum (0.50 ng/ml [0.21-1.23]) than 1-4 days post-partum (0.18 ng/ml [0.06-0.40]), P < 0.001. The two results for each participant were highly correlated (r = 0.82, P < 0.001). The extended fertility and control groups were similar regarding age, age at menarche, past CHC use and history of fertility concern. Parity differed but showed no significant correlation with AMH. CONCLUSIONS: Serum AMH concentrations that reflect ovarian reserve do not seem to predict reproductive potential at highly advanced age. Thus, additional factors such as oocyte quality should also be considered in evaluating reproductive potential. AMH suppression that is associated with pregnancy at 1-4 days post-partum recovers at 3-11 months post-partum in women of highly advanced reproductive age.

Leukocyte Telomere Length Correlates with Extended Female Fertility.

Current social trends of delayed reproduction to the fourth and fifth decade of life call for a better understanding of reproductive aging. Demographic studies correlated late reproduction with general health and longevity. Telomeres, the protective ends of eukaryotic chromosomes, were implicated in various aging-associated pathologies and longevity. To examine whether telomeres are also associated with reproductive aging, we measured by Southern analysis the terminal restriction fragments (TRF) in leukocytes of women delivering a healthy infant following a spontaneous pregnancy at 43-48 years of age. We compared them to age-matched previously fertile women who failed to conceive above age 41. The average TRF length in the extended fertility group (9350 bp) was significantly longer than in the normal fertility group (8850 bp; p-value = 0.03). Strikingly, excluding women with nine or more children increased the difference between the groups to over 1000 bp (9920 and 8880 bp; p-value = 0.0009). Nevertheless, we observed no apparent effects of pregnancy, delivery, or parity on telomere length. We propose that longer leukocyte telomere length reflects higher oocyte quality, which can compensate for other limiting physiological and behavioral factors and enable successful reproduction. Leukocyte telomere length should be further explored as a novel biomarker of oocyte quality for assessing reproductive potential and integrating family planning with demanding women's careers.

DMPK hypermethylation in sperm cells of myotonic dystrophy type 1 patients.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant muscular dystrophy that results from a CTG expansion (50-4000 copies) in the 3' UTR of the DMPK gene. The disease is classified into four or five somewhat overlapping forms, which incompletely correlate with expansion size in somatic cells of patients. With rare exception, it is affected mothers who transmit the congenital (CDM1) and most severe form of the disease. Why CDM1 is hardly ever transmitted by fathers remains unknown. One model to explain the almost exclusive transmission of CDM1 by affected mothers suggests a selection against hypermethylated large expansions in the germline of male patients. By assessing DNA methylation upstream to the CTG expansion in motile sperm cells of four DM1 patients, together with availability of human embryonic stem cell (hESCs) lines with paternally inherited hypermethylated expansions, we exclude the possibility that DMPK hypermethylation leads to selection against viable sperm cells (as indicated by motility) in DM1 patients.

Hypogonadism in Women with Prader-Willi Syndrome-Clinical Recommendations Based on a Dutch Cohort Study, Review of the Literature and an International Expert Panel Discussion.

Prader-Willi syndrome (PWS) is a rare neuroendocrine genetic syndrome. Characteristics of PWS include hyperphagia, hypotonia, and intellectual disability. Pituitary hormone deficiencies, caused by hypothalamic dysfunction, are common and hypogonadism is the most prevalent. Untreated hypogonadism can cause osteoporosis, which is already an important issue in PWS. Therefore, timely detection and treatment of hypogonadism is crucial. To increase understanding and prevent undertreatment, we (1) performed a cohort study in the Dutch PWS population, (2) thoroughly reviewed the literature on female hypogonadism in PWS and (3) provide clinical recommendations on behalf of an international expert panel. For the cohort study, we retrospectively collected results of a systematic health screening in 64 female adults with PWS, which included a medical questionnaire, medical file search, medical interview, physical examination and biochemical measurements. Our data show that hypogonadism is frequent in females with PWS (94%), but is often undiagnosed and untreated. This could be related to unfamiliarity with the syndrome, fear of behavioral changes, hygienic concerns, or drug interactions. To prevent underdiagnosis and undertreatment, we provide practical recommendations for the screening and treatment of hypogonadism in females with PWS.

Identifying regulators of parental imprinting by CRISPR/Cas9 screening in haploid human embryonic stem cells.

In mammals, imprinted genes are regulated by differentially methylated regions (DMRs) that are inherited from germ cells, leading to monoallelic expression in accordance with parent-of-origin. Yet, it is largely unknown how imprinted DMRs are maintained in human embryos despite global DNA demethylation following fertilization. Here, we explored the mechanisms involved in imprinting regulation by employing human parthenogenetic embryonic stem cells (hpESCs), which lack paternal alleles. We show that although global loss of DNA methylation in hpESCs affects most imprinted DMRs, many paternally-expressed genes (PEGs) remain repressed. To search for factors regulating PEGs, we performed a genome-wide CRISPR/Cas9 screen in haploid hpESCs. This revealed ATF7IP as an essential repressor of a set of PEGs, which we further show is also required for silencing sperm-specific genes. Our study reinforces an important role for histone modifications in regulating imprinted genes and suggests a link between parental imprinting and germ cell identity.

Hypogonadism in Adult Males with Prader-Willi Syndrome-Clinical Recommendations Based on a Dutch Cohort Study, Review of the Literature and an International Expert Panel Discussion.

Prader-Willi syndrome (PWS) is a complex genetic syndrome characterized by hyperphagia, intellectual disability, hypotonia and hypothalamic dysfunction. Adults with PWS often have hormone deficiencies, hypogonadism being the most common. Untreated male hypogonadism can aggravate PWS-related health issues including muscle weakness, obesity, osteoporosis, and fatigue. Therefore, timely diagnosis and treatment of male hypogonadism is important. In this article, we share our experience with hypogonadism and its treatment in adult males with PWS and present a review of the literature. In order to report the prevalence and type of hypogonadism, treatment regimen and behavioral issues, we retrospectively collected data on medical interviews, physical examinations, biochemical measurements and testosterone replacement therapy (TRT) in 57 Dutch men with PWS. Fifty-six (98%) of the patients had either primary, central or combined hypogonadism. Untreated hypogonadism was associated with higher body mass index and lower hemoglobin concentrations. TRT was complicated by behavioral challenges in one third of the patients. Undertreatment was common and normal serum testosterone levels were achieved in only 30% of the patients. Based on the Dutch cohort data, review of the literature and an international expert panel discussion, we provide a practical algorithm for TRT in adult males with PWS in order to prevent undertreatment and related adverse health outcomes.

Expanded clinical validation of Haploseek for comprehensive preimplantation genetic testing.

PURPOSE: We previously developed Haploseek, a method for comprehensive preimplantation genetic testing (PGT). However, some key features were missing, and the method has not yet been systematically validated. METHODS: We extended Haploseek to incorporate DNA from embryo grandparents and to allow testing of variants on chromosome X or in regions where parents share common haplotypes. We then validated Haploseek on 151 embryo biopsies from 27 clinical PGT cases. We sequenced all biopsies to low coverage (0.2×), and performed single-nucleotide polymorphism (SNP) microarray genotyping on the embryos' parents and siblings/grandparents. We used the extended Haploseek to predict chromosome copy-number variants (CNVs) and relevant variant-flanking haplotypes in each embryo. We validated haplotype predictions for each clinical sample against polymerase chain reaction (PCR)-based PGT case results, and CNV predictions against established commercial kits. RESULTS: For each of the 151 embryo biopsies, all Haploseek-derived haplotypes and CNVs were concordant with clinical PGT results. The cases included 17 autosomal dominant, 5 autosomal recessive, and 3 X-linked monogenic disorders. In addition, we evaluated 1 Robertsonian and 2 reciprocal translocations, and 17 cases of chromosome copy-number counting were performed. CONCLUSION: Our results demonstrate that Haploseek is clinically accurate and fit for all standard clinical PGT applications.

Preimplantation genetic testing (PGT) for copy number variants of uncertain significance (CNV- VUS) in the genomic era: to do or not to do?

PURPOSE: To review cases of couples presented to our PGT-unit with copy number variants (CNVs) classified as variants of uncertain significance (VUS) in order to better understand their needs. METHODS: Retrospective cohort study conducted in a tertiary medical-center, 2014-2019. We reviewed files of all couples applying for genetic counseling with CNVs classified as VUS. The main outcomes measured: number of VUS findings and their description, PGT-M procedures planned and performed, IVF cycles, clinical pregnancy, and live birth rates (LBR). VUS were classified according to the American-College of Medical-Genetics and Genomics classification at time of first consultation, and updated-December 2018. RESULTS: Twenty-four couples presented with a total of 30 VUS. Twelve couples (50%) had isolated VUS and 12 (50%) had VUS diagnosed in addition to a pathogenic mutation. Initially, nine findings (30%) were defined as VUS; eight (27%) as likely benign (b-VUS); and 13 (43%) as likely pathogenic (p-VUS). PGT-M was recommended for 17/30 CNVs (56.6%), 12 (70%) of which, isolated VUS. No couple had other indications for IVF. To date, nine couples performed PGT-M for isolated VUS; LBR per-couple-55.5%. Five couples performed PGT-M for both pathogenic findings and VUS, LBR-80%. After reviewing VUS classifications, 30% remained unchanged, 20% were more severely defined, and 50% less severely defined. CONCLUSION: The genomic era enables detection of VUS whose definition is subject to change as additional information becomes available. The uncertainty of variants' clinical significance and changes in VUS definition over time complicates genetic counseling. Revised guidelines for VUS interpretation and reevaluation of patient counseling before each pregnancy must be practiced when counseling them regarding the justification of PGT-M for their diagnosed VUS.

Recognizing the unique prenatal phenotype of Prader-Willi Syndrome (PWS) indicates the need for a diagnostic methylation test.

OBJECTIVES: Prader-Willi syndrome (PWS) is a neurogenetic disorder characterized by mental retardation, morbid obesity, and endocrine and behavior disorders. We previously showed in a small group of patients that PWS may have a unique prenatal phenotype. We aimed to characterize clinical and ultrasonic features in a larger series of pregnancies with a PWS fetus. METHODS: We retrospectively interviewed all mothers of children with PWS followed in the Israel national multidisciplinary PWS clinic. We compared details of the PWS pregnancy with the pregnancies of healthy siblings and with data from the general population. Medical records including ultrasound reports, obstetric records, and genetic results were analyzed. RESULTS: Distinct prenatal features of PWS pregnancies included abnormal fetal growth [fetal growth restriction (FGR) (37.3%), increased head to abdominal circumference ratio (44.8%), decreased abdominal circumference (49.2%)], markedly decreased fetal movements (DFM) (80.4%), and polyhydramnios (42.0%) (P < 0.001 for all). The combination of abnormal growth accompanied by polyhydramnios or DFM was highly suggestive for PWS. CONCLUSIONS: Recognition of the unique PWS phenotype should alert obstetricians to consider the possibility of PWS, perform the diagnostic methylation test, provide appropriate counseling, and plan optimal management of the affected pregnancy.

Cancer in IVF patients treated at age 40 years and older: long term follow-up.

RESEARCH QUESTION: Current knowledge of cancer risk among women who undergo IVF is based mainly on studies of women treated in their thirties, frequently with short follow-up periods. Therefore, information about cancer risk among infertile menopausal women is limited. We aimed to evaluate the risk of cancer among IVF patients treated at age 40 years and older, followed up for an extended period. DESIGN: Historical cohort study of all IVF patients treated at the age of 40 years or older at two university-affiliated IVF units in Jerusalem, Israel, between 1994 and 2002. Data were cross-linked with the Israel National Cancer Registry to 2016. Standardized incidence ratios (SIR) and 95% confidence intervals were computed by comparing the observed number of cancer cases with the expected cancer rate in the general Israeli population adjusted for age and year of birth. In addition, Kaplan-Meier analysis was conducted to account for the length of follow-up. RESULTS: A total of 501 patients were included in the analysis, with mean follow-up of 16.7 ± 3.7 years (range 2-22 years). Mean age at first IVF cycle was 42.3 years (±2.1). Mean number of IVF cycles was 3.2 ± 2.6 (range 1-15). Thirty-six women (7.2%) developed invasive cancer, compared with 47.2 expected cases; SIR 0.76 (95% CI 0.53 to 1.06); 22 women were diagnosed with invasive breast cancer, compared with 19.84 expected; SIR 1.11 (95% CI 0.69 to 1.68). CONCLUSIONS: Older women undergoing IVF treatment were not significantly associated with an excess risk of cancer at long-term follow up. Further studies, however, are needed to confirm these findings.

Global Characterization of X Chromosome Inactivation in Human Pluripotent Stem Cells.

Dosage compensation of sex-chromosome gene expression between male and female mammals is achieved via X chromosome inactivation (XCI) by employing epigenetic modifications to randomly silence one X chromosome during early embryogenesis. Human pluripotent stem cells (hPSCs) were reported to present various states of XCI that differ according to the expression of the long non-coding RNA XIST and the degree of X chromosome silencing. To obtain a comprehensive perspective on XCI in female hPSCs, we performed a large-scale analysis characterizing different XCI parameters in more than 700 RNA high-throughput sequencing samples. Our findings suggest differences in XCI status between most published samples of embryonic stem cells (ESCs) and induced PSCs (iPSCs). While the majority of iPSC lines maintain an inactive X chromosome, ESC lines tend to silence the expression of XIST and upregulate distal chromosomal regions. Our study highlights significant epigenetic heterogeneity within hPSCs, which may bear implications for their use in research and regenerative therapy.

The effect of repeated biopsy on pre-implantation genetic testing for monogenic diseases (PGT-M) treatment outcome.

PURPOSE: To study the outcome of repeated biopsy for pre-implantation genetic testing in case of failed genetic diagnosis in the first biopsy. METHODS: The study group included 81 cycles where embryos underwent re-biopsy because there were no transferable embryos after the first biopsy: in 55 cycles, the first procedure was polar body biopsy (PBs) and the second cleavage-stage (BB); in 26 cycles, the first was BB and the second trophectoderm (BLAST) biopsy. The control group included 77 cycles where embryos underwent successful genetic diagnosis following the first biopsy, matched by maternal age, egg number, genetic inheritance type, and embryonic stage at the first biopsy. We measured genetic diagnosis rate, clinical pregnancy rates (PRs), live-birth rates (LBRs), gestational age, and birth weight. RESULTS: For repeated biopsy, genetic diagnosis was received in 67/81 cycles (82.7%); at a higher rate in PB + BB than in BB + BLAST (49/55, 89.1% and 18/26, 69.2% respectively, p = 0.055). Transferable embryos were found in 47 and 68 cycles in the study and the control groups. PRs/ET were 20/47 (42.6%) and 36/68 (52.9%) (p = 0.27), 16/36 (44.4%) following PB + BB, and 4/11 (36.4%) following BB + BLAST (p = 0.74). LBRs/ET were 13/47 (27.7%) in study group, and 28/68 (41.2%) in the controls (p = 0.14), 10/36 (27.8%) following PB + BB group, and 3/11 (27.3%) following BB + BLAST (p > 0.99). Gestational age and birth weight were similar in all groups. CONCLUSIONS: Re-biopsy of embryos when no genetic diagnosis could be reached following the first biopsy, achieved high rates of genetic diagnosis, pregnancies, and live births.

Noninvasive paternal exclusion testing for cystic fibrosis in the first five to eight weeks of gestation.

Prenatal genetic testing is not generally applicable to the very early stages of pregnancy (prior to week 8 gestation), a time period that is crucial to pregnant couples with high risk for transmission of genetic disease to their fetus. Therefore, we developed a new ultra-sensitive targeted next generation sequencing method for noninvasive haplotype-based paternal allele exclusion testing of the cystic fibrosis-associated gene, CFTR. This new method was compared to a conventional library prep and sequencing analysis method and all test results were validated by amniotic fluid testing at later stages of pregnancy. Out of 7 enrolled couples, who provided at least two blood samples (at least one week apart) for noninvasive CFTR testing, a result was obtained for 6 fetuses. Using the new hypersensitive method, all six couples (100%) received a correct diagnosis for the paternal allele as opposed to 3/6 (50%) when tested with the conventional strategy. Among 4 couples who provided just one early pregnancy blood draw for analysis, diagnosis was possible in one fetus, but only using the ultra-sensitive method. Thus, we describe a novel noninvasive CFTR screening method which demonstrates unprecedented fetal allele typing accuracy in the earliest stages of pregnancy.