M.J. Glassner

Clinical utilisation of a rapid low-pass whole genome sequencing technique for the diagnosis of aneuploidy in human embryos prior to implantation

Background The majority of human embryos created using in vitro fertilisation (IVF) techniques are aneuploid. Comprehensive chromosome screening methods, applicable to single cells biopsied from preimplantation embryos, allow reliable identification and transfer of euploid embryos. Recently, randomised trials using such methods have indicated that aneuploidy screening improves IVF success rates. However, the high cost of testing has restricted the availability of this potentially beneficial strategy. This study aimed to harness next-generation sequencing (NGS) technology, with the intention of lowering the costs of preimplantation aneuploidy screening. Methods Embryo biopsy, whole genome amplification and semiconductor sequencing. Results A rapid (<15 h) NGS protocol was developed, with consumable cost only two-thirds that of the most widely used method for embryo aneuploidy detection. Validation involved blinded analysis of 54 cells from cell lines or biopsies from human embryos. Sensitivity and specificity were 100%. The method was applied clinically, assisting in the selection of euploid embryos in two IVF cycles, producing healthy children in both cases. The NGS approach was also able to reveal specified mutations in the nuclear or mitochondrial genomes in parallel with chromosome assessment. Interestingly, elevated mitochondrial DNA content was associated with aneuploidy (p<0.05), a finding suggestive of a link between mitochondria and chromosomal malsegregation. Conclusions This study demonstrates that NGS provides highly accurate, low-cost diagnosis of aneuploidy in cells from human preimplantation embryos and is rapid enough to allow testing without embryo cryopreservation. The method described also has the potential to shed light on other aspects of embryo genetics of relevance to health and viability.

Idiopathic recurrent miscarriage is caused mostly by aneuploid embryos.

OBJECTIVE To determine any beneficial effects of preimplantation genetic screening (PGS) of all chromosomes by array comparative genomic hybridization (aCGH), with either day 3 or blastocyst biopsy, for idiopathic recurrent pregnancy loss (RPL) patients compared with their expected loss rate. DESIGN Case series report. SETTING Multiple fertility centers. PATIENT(S) A total of 287 cycles of couples with idiopathic RPL (defined as two or more losses). INTERVENTION(S) PGS was done with day 3 biopsy (n = 193) or blastocyst biopsy (n = 94), followed by analysis with aCGH. MAIN OUTCOME MEASURE(S) Spontaneous abortion rate, euploidy rate. RESULT(S) A total of 2,282 embryos were analyzed, of which 35% were euploid and 60% were aneuploid. There were 181 embryo transfer cycles, of which 100 (55%) became pregnant with an implantation rate of 45% (136 sacs/299 replaced embryos) and 94 pregnancies (92%) were ongoing (past second trimester) or delivered. The miscarriage rate was found to be only 6.9% (7/102), compared with the expected rate of 33.5% in an RPL control population and 23.7% in an infertile control population. CONCLUSION(S) Current PGS results with aCGH indicate a significant decrease in the miscarriage rate of idiopathic RPL patients and high pregnancy rates. Furthermore, this suggests that idiopathic recurrent miscarriage is mostly caused by chromosomal abnormalities in embryos.

Array CGH analysis shows that aneuploidy is not related to the number of embryos generated

This study retrospectively analysed array comparative genomic hybridization (CGH) results of 7753 embryos from 990 patients to determine the frequency of embryonic euploidy and its relationship with the cohort size (i.e. the number of embryos available for biopsy and array CGH analysis). Linear regression analysis was performed to assess the effect of cohort size on euploidy rate adjusted for the effect of female age. While increasing female age was associated with a significant decrease in euploidy rate of day-3 and day-5 embryos (P<0.001 for both groups), cohort size was not significantly associated with euploidy rate. Logistic regression analysis was performed to assess the effect of cohort size, adjusted for maternal age, on the likelihood of having at least one euploid embryo available for transfer. The odds of having at least one euploid embryo in an assisted cycle was significantly decreased by increasing female age (P<0.01 for both day-3 and day-5 embryos) and was significantly increased by every additional embryo available for analysis (P<0.001 for both day-3 and day-5 embryos).

The effects of different laser pulse lengths on the embryo biopsy procedure and embryo development to the blastocyst stage.

PurposeA laser is commonly used to remove a blastomere from an embryo for genetic testing. The laser uses intense heat which could possibly disrupt embryo development. It is the goal of this study to test the effects of different laser pulse lengths (and consequently heat) on the embryo biopsy procedure and embryo development.MethodsEach embryo biopsy was performed randomly utilizing laser pulse lengths of 0.604mS (group I), 0.708mS (group II), and 1.010mS (group III).ResultsFor groups I, II, and III, 83, 86, and 71 embryos were biopsied, respectively. There was no difference in day 5 embryo quality or lysed blastomeres between groups. Average number of blastomeres biopsied between group I (1.0 ± 0.0), II (1.0 ± 0.2), and III (1.1 ± 0.2) was significant (0.0001).ConclusionOur data demonstrates that laser pulse length does not influence the embryo biopsy procedure or embryo development.

The utility of embryo banking in order to increase the number of embryos available for preimplantation genetic screening in advanced maternal age patients

PurposeTo determine if embryo banking with PGS is more optimal than proceeding with PGS regardless of embryo number.MethodsPatients were divided into 2 groups, group 1 were those that banked embryos and proceeded through another round of IVF prior to PGS, and group 2 underwent PGS regardless of embryo number. Group 2 was divided into group 2A (patients with >10 embryos) and group 2B (patients who had <10 embryos).ResultsThere was no difference in embryos biopsied, normal embryos, number transferred, and pregnancy rate between group 1 and 2. A significant number of patients did not have a transfer in group 2B (6/11) compared to group 1 (3/19) (P = 0.0419). There was no significance between pregnancy rates per transfer between group 1 (6/16) and group 2B (2/5).ConclusionOur data suggests that banking will increase the odds of going to transfer but there was no increase in pregnancy rates.

Pregnancy after rebiopsy and vitrification of blastocysts following allele dropout after day 3 biopsy

OBJECTIVE To report a clinical pregnancy after rebiopsy and vitrification of blastocysts following allele dropout (ADO) of biopsied day 3 embryos. DESIGN Case report. SETTING Private center. PATIENT(S) Thirty-year-old woman and her 33-year-old husband who carries the single-gene condition paraganglioma. INTERVENTION(S) In vitro fertilization with day 3 embryo biopsy-ET-blastocyst biopsy and vitrification-subsequent frozen ET cycle. MAIN OUTCOME MEASURE(S) Results from preimplantation genetic diagnosis and pregnancy results after fresh and frozen ETs. RESULT(S) Nineteen oocytes were retrieved of which 13 were mature and 12 fertilized. Eleven embryos were biopsied on day 3: two were normal, five were affected, and four exhibited ADO. The two normal blastocysts were transferred, and three of the ADO blastocysts were biopsied and sent for reanalysis. The biopsied blastocysts were vitrified. No pregnancy resulted from the fresh ET. One of the biopsied blastocysts was normal, one received no result, and one exhibited ADO. A singleton clinical pregnancy resulted from a subsequent frozen ET of the thawed biopsied normal blastocyst. CONCLUSION(S) Rebiopsy and vitrification of blastocysts could be used in cases of ADO or lack of results after day 3 embryo biopsy.

Hemivaginal Septum Resection in a Patient With a Rare Variant of Herlyn-Werner-Wunderlich Syndrome

Herlyn-Werner-Wunderlich syndrome is characterized by a triad of uterine didelphys, obstructed hemivagina, and ipsilateral renal agenesis. The syndrome should be suspected in any young woman with abdominal pain or cyclic dysmenorrhea, and radiologic evidence of müllerian duct and renal anomalies. Herein is presented the case of a 25-year-old woman with a rare variant of Herlyn-Werner-Wunderlich syndrome, characterized by an anomalous connection between the 2 endocervical canals, who underwent hemivaginal septum resection to relieve progressively worsening dysmenorrhea. The right hemivaginal septum was resected medially from the left cervix and laterally off the right vaginal wall. Hydrodissection between the hemivaginal septum and right cervix facilitated surgical resection. After resection of the hemivaginal septum there was complete resolution of dysmenorrhea and no recurrence of hematometra or hematocolpos.