Comparison of the number of oocytes obtained after ovarian stimulation between Chinese and Caucasian women undergoing in vitro fertilization using a standardized stimulation regime.

BACKGROUND: In vitro fertilization (IVF) is a well-established method to treat various causes of infertility. Some previous retrospective studies suggested a lower ovarian response in Asian women compared to Caucasian women. However, the ovarian stimulation regimens were not standardized, potentially confounding the findings. The objective of this study is to compare the number of oocytes obtained after ovarian stimulation between Chinese and Caucasian women undergoing IVF using a standardized stimulation regimen. METHODS: This is a prospective cohort study conducted in two tertiary IVF units in Hong Kong, China and Sydney, Australia from October 2016 to August 2019. A total of 192 women aged 18-42 years with a body weight > 60 kg underwent IVF with a standard ovarian stimulation regimen of 150 micrograms corifollitropin alfa (Elonva®) followed by 200 IU follitropin beta (Puregon®) per day. The number of oocytes retrieved in Chinese women treated in the Hong Kong center was compared to that of Caucasian women treated in the Australian center. RESULTS: Serum AMH levels were similar between the two groups. Although women in the Chinese cohort were older and had a higher body mass index (BMI), longer duration of infertility and lower antral follicle count (AFC) than those in the Caucasian cohort in this study, no differences in the number of oocytes retrieved [11 (8-17) vs. 11 (6-17), p=0.29], total dosage and duration of stimulation and number of follicles aspirated were noted between the two ethnic cohorts. The peak estradiol level was greater in Chinese women than in Caucasian women. After controlling for age, BMI and AFC, ethnicity was a significant independent determinant of the number of oocytes obtained. CONCLUSIONS: Chinese women had a higher number of oocytes after ovarian stimulation using a standardized stimulation regimen compared with Caucasian women undergoing IVF after controlling for age, BMI, AFC and AMH despite presenting later after a longer duration of infertility. TRIAL REGISTRATION NUMBER: NCT02748278.

Knowledge, attitude and ethical consideration of Chinese couples requesting preimplantation genetic testing in Hong Kong.

AIM: Increasing preimplantation genetic testing (PGT) cycles are being performed in Hong Kong. This study aims to evaluate the knowledge, attitude and ethical consideration of Chinese couples toward PGT. METHODS: Couples requesting PGT between June 2013 and March 2014 were invited to complete a questionnaire. RESULTS: Total 49 couples (49 women, 47 men) completed the questionnaires. Eighteen couples (37%) were waiting for PGT (pre-PGT group), 15 couples (31%) were undergoing PGT (PGT group) and 16 couples (32%) had completed at least one PGT cycle (post-PGT group). Only 53% of the couples could tell the recurrent risk, and 31% (with monogenic disorders) could tell the mode of inheritance of their condition. The acceptability of PGT (>80%) and attitude toward the embryo fate (58-78%) were good. The post-PGT group had more concern than the PGT and pre-PGT groups on the prenatal diagnostic testing (**P = 0.007). 12.5% of the couples worried about the transfer of healthy embryos with carrier state and they all had monogenic disorders. If the prenatal testing confirmed an affected fetus, a higher percentage (32%) in the Post-PGT group disagreed to terminate the pregnancy in contrast to a much lower 6% in the pre-PGT group (**P = 0.02). Three-quarter of the couples opted to tell their child about their conception through PGT. CONCLUSION: Chinese couples in Hong Kong had an overall good acceptability and positive attitude toward PGT. We appreciate the difficulties the couples have gone through PGT. A checklist on what to cover pre-during-post-PGT in the counseling process is needed.

Evaluation of preimplantation genetic testing for chromosomal structural rearrangement by a commonly used next generation sequencing workflow.

OBJECTIVES: To evaluate the applicability of a commonly used next generation sequencing workflow in detecting unbalanced meiotic segregation products for reciprocal translocation and inversion carriers. STUDY DESIGN: All preimplantation genetic testing treatment cycles performed for reciprocal translocation or inversion carriers from 2012 to April 2017 were included. Three hundreds and forty-two archived whole genome amplified DNA, which had previously analyzed by array comparative genomic hybridization (aCGH), were retrospectively analyzed by next generation sequencing (NGS). Concordance on overall diagnosis and segmental aneuploidies related to the translocation/inversion breakpoints between aCGH and NGS were determined. RESULTS: Retrospective analysis of 287 blastomere biopsies and 55 trophectoderm (TE) biopsies showed that the concordance rate on the overall diagnosis between aCGH and NGS on abnormal samples was 100% (266/266), irrespective to the type of biopsy. The concordance rates of normal biopsies were 98.4% (61/62) on blastomere and 78.6% (11/14) on TE biopsies. NGS detected a de novo segmental aneuploidy on one blastomere biopsy and three possible low level mosaic aneuploidies on 3 TE biopsies, which were previously concluded as euploid by aCGH. Using the karyotype of reciprocal translocation/inversion carriers, size of anticipated segmental aneuploidies could be calculated and be used to predict the applicability of NGS before proceeding to treatment. CONCLUSION: This is the first report to evaluate the applicability of a commercial NGS-based workflow for preimplantation testing for reciprocal translocations/inversions. Our study demonstrated that NGS can diagnose unbalanced translocation/inversion products with the same efficiency as aCGH. The applicability of NGS, with respect to individual karyotype, can be predicted before proceeding to treatment.

Experience of more than 100 preimplantation genetic diagnosis cycles for monogenetic diseases using whole genome amplification and linkage analysis in a single centre.

OBJECTIVE: To report the outcomes of more than 100 cycles of preimplantation genetic diagnosis for monogenetic diseases. DESIGN: Case series. SETTING: Tertiary assisted reproductive centre in Hong Kong, where patients needed to pay for the cost of preimplantation genetic diagnosis on top of standard in-vitro fertilisation charges. PATIENTS: Patients undergoing preimplantation genetic diagnosis for monogenetic diseases at the Centre of Assisted Reproduction and Embryology, Queen Mary Hospital-The University of Hong Kong between 1 August 2007 and 30 April 2014 were included. INTERVENTIONS: In-vitro fertilisation, intracytoplasmic sperm injection, embryo biopsy, and preimplantation genetic diagnosis. MAIN OUTCOME MEASURES: Ongoing pregnancy rate and implantation rate. RESULTS: Overall, 124 cycles of preimplantation genetic diagnosis were initiated in 76 patients, 101 cycles proceeded to preimplantation genetic diagnosis, and 92 cycles had embryo transfer. The ongoing pregnancy rate was 28.2% per initiated cycle and 38.0% per embryo transfer, giving an implantation rate of 35.2%. There were 16 frozen-thawed embryo transfer cycles in which, following preimplantation genetic diagnosis, cryopreserved embryos were replaced resulting in an ongoing pregnancy rate of 37.5% and implantation rate of 30.0%. The cumulative ongoing pregnancy rate was 33.1%. The most frequent indication for preimplantation genetic diagnosis was thalassaemia, followed by neurodegenerative disorder and cancer predisposition. There was no misdiagnosis. CONCLUSIONS: Preimplantation genetic diagnosis is a reliable method to prevent couples conceiving fetuses severely affected by known genetic disorders, with ongoing pregnancy and implantation rates similar to those for in-vitro fertilisation for routine infertility treatment.

Comparison between fluorescent in-situ hybridisation and array comparative genomic hybridisation in preimplantation genetic diagnosis in translocation carriers.

OBJECTIVES: To compare the pregnancy outcome of the fluorescent in-situ hybridisation and array comparative genomic hybridisation in preimplantation genetic diagnosis of translocation carriers. DESIGN: Historical cohort. SETTING: A teaching hospital in Hong Kong. PATIENTS: All preimplantation genetic diagnosis treatment cycles performed for translocation carriers from 2001 to 2013. RESULTS: Overall, 101 treatment cycles for preimplantation genetic diagnosis in translocation were included: 77 cycles for reciprocal translocation and 24 cycles for Robertsonian translocation. Fluorescent in-situ hybridisation and array comparative genomic hybridisation were used in 78 and 11 cycles, respectively. The ongoing pregnancy rate per initiated cycle after array comparative genomic hybridisation was significantly higher than that after fluorescent in-situ hybridisation in all translocation carriers (36.4% vs 9.0%; P=0.010). The miscarriage rate was comparable with both techniques. The testing method (array comparative genomic hybridisation or fluorescent in-situ hybridisation) was the only significant factor affecting the ongoing pregnancy rate after controlling for the women's age, type of translocation, and clinical information of the preimplantation genetic diagnosis cycles by logistic regression (odds ratio=1.875; P=0.023; 95% confidence interval, 1.090-3.226). CONCLUSION: This local retrospective study confirmed that comparative genomic hybridisation is associated with significantly higher pregnancy rates versus fluorescent in-situ hybridisation in translocation carriers. Array comparative genomic hybridisation should be the technique of choice in preimplantation genetic diagnosis cycles in translocation carriers.

Array comparative genomic hybridization analyses of all blastomeres of a cohort of embryos from young IVF patients revealed significant contribution of mitotic errors to embryo mosaicism at the cleavage stage.

BACKGROUND: Embryos produced by in vitro fertilization (IVF) have a high level of aneuploidy, which is believed to be a major factor affecting the success of human assisted reproduction treatment. The aneuploidy rate of cleavage stage embryos based on 1-2 biopsied blastomeres has been well-reported, however, the true aneuploidy rate of whole embryos remain unclear because of embryo mosaicism. To study the prevalence of mosaicism in top quality IVF embryos, surplus embryos donated from young patients (aged 28-32) in the assisted reproduction program at Queen Mary Hospital, Hong Kong were used. METHODS: Thirty-six good quality day 2 embryos were thawed. Out of the 135 blastomeres in these embryos, 121 (89.6%) survived thawing. Twelve of these embryos without lysed blastomeres and which cleaved to at least seven cells after a 24-h culture were dissembled into individual blastomeres, which were analysed by array comparative genomic hybridization and microsatellite marker analysis by fluorescent PCR. RESULTS: Out of 12 day-3 embryos, 2 (16.7%) were normal, 3 (25%) were diploid/aneuploidy with <38% abnormality, 4 (33.3%) were diploid/aneuploidy mosaic with > =38% abnormality, and three (25%) were mosaic aneuploids. Conclusive chromosomal data were obtained from a high percentage of blastomeres (92.8%, 90/97). Microsatellite marker analysis performed on blastomeres in aneuploid embryos enabled us to reconstruct the chromosomal status of the blastomeres in each cleavage division. The results showed the occurrence of meiotic errors in 3 (25%) of the studied embryos. There were 16 mitotic errors (18.8%, 16/85) in the 85 mitotic divisions undertaken by the studied embryos. The observed mitotic errors were mainly contributed by endoreduplication (31.3%, 5/16), non-disjunction (25%, 4/16) and anaphase lagging (25%, 4/16). Chromosome breakages occurred in 6 divisions (7.1%, 6/85). CONCLUSIONS: Mosaicism occurs in a high percentage of good-quality cleavage stage embryos and mitotic errors contribute significantly to the abnormality.

Preimplantation genetic diagnosis using combined strategies on a breast cancer patient with a novel genomic deletion in BRCA2.

PURPOSE: To perform Preimplantation Genetic Diagnosis (PGD) on a paternal Brca2 unknown mutation carrier with early-onset breast cancer, whose paternal grandmother and mother had breast cancer at 60s. METHOD: Elucidating the linkage via single sperm haplotyping on patient's carrier brother, and identifying the genomic deletion via BLAST followed by PCR screening. PGD was subsequently conducted. RESULT: The mutant allele was found by using 4 microsatellite and 2 intragenic SNP markers. Recombination was detected in 8% of sperms. BLAST was utilized to locate putative hairpin structure(s), followed by PCR screening with seven sets of primers. A novel 2,596 bp deletion containing exon 15 ~ 16 was identified. Due to the severity of phenotype and the integrity of exon 11 encoding RAD51 binding domain, and the fact that the patient's mother also had breast cancer at her 60s, we speculate a possible coexistence of maternal breast cancer risk allele(s). Embryo biopsy was performed on day 3. Unaffected morula and blastocyst were replaced on day 5, resulting in a singleton livebirth. A breast lump appeared in the patient after delivery without the presence of malignant cells. CONCLUSION: Concerning the assisted reproductive option for breast cancer patients, the possibility of coexistence of multiple familial risk alleles and the significance of each mutation to the phenotype should be evaluated. To eliminate misdiagnosis resulting from recombination and/or allelic drop-out, both direct mutation detection and linkage analysis approaches may be necessary. BLAST is a very useful and cost-effective tool for identifying large genomic deletion.

Live birth following double-factor pre-implantation genetic diagnosis for both reciprocal translocation and alpha-thalassaemia.

We report a live birth from a couple with two genetic diseases, namely: reciprocal translocation carrier and alpha-thalassaemia trait, following pre-implantation genetic diagnostic tests. This is the first case in Hong Kong in which the technique of using one blastomere biopsy for two diseases was established, using array comparative genomic hybridisation and polymerase chain reaction.

Role of baseline antral follicle count and anti-Mullerian hormone in the index stimulation cycle of IVF treatment in predicting outcome of subsequent frozen-thawed embryo transfers.

This retrospective cohort study aims at determining whether baseline antral follicle count (AFC) and serum anti-Mullerian hormone (AMH) level in the index stimulation cycle predict live-birth outcome in subsequent frozen-thawed embryo transfer (FET) cycles. We studied 500 women undergoing the first IVF cycle who had embryo(s) cryopreserved. The main outcome measures were live-birth in the first FET cycle and cumulative live-birth in all the FETs combined after the same stimulation cycle. Our results showed that baseline AFC and AMH level on the day before ovarian stimulation showed significant correlation. In the first FET cycle, AFC and AMH level were significantly higher in subjects attaining live-birth in the first FET cycle or cumulative live-birth from all FETs than those who did not. Both AMH and AFC were insignificant predictors of live-birth in the first FET cycle or cumulative live-birth after adjusting for age. The areas under the ROC curves for AMH, AFC and age were 0.654, 0.625 and 0.628, respectively, for predicting cumulative live-birth. In conclusion, we reported for the first time that baseline AFC and AMH in the index stimulation cycle have only modest predictive performance on cumulative live-birth in subsequent FET cycles.

Live birth rate, multiple pregnancy rate, and obstetric outcomes of elective single and double embryo transfers: Hong Kong experience.

OBJECTIVE: To compare the live birth rate, multiple pregnancy rate, and obstetric outcomes of elective single and double embryo transfers. DESIGN: Case series with internal comparisons. SETTING: University affiliated hospital, Hong Kong. PARTICIPANTS: Between October 2009 and December 2011, 206 women underwent their first in-vitro fertilisation cycle. Elective single embryo transfer was offered to women who were aged 35 years or below, and had endometrial thickness of 8 mm or more and at least two embryos of good quality. MAIN OUTCOME MEASURES: Live birth rate, multiple birth rate, and obstetric outcomes. RESULTS: Among the 206 eligible women, 74 underwent an elective single embryo transfer and 132 a double embryo transfer. The live birth rate was comparable in the two groups, being 39.2% in the elective single embryo transfer group and 43.2% in the double embryo transfer group, while the multiple pregnancy rate was significantly lower in the elective single embryo transfer group than the double embryo transfer group (6.9% vs 40.4%; P<0.001). Gestational ages and birth weights were comparable in the two groups. There was no significant difference between the two groups with respect to the rate of preterm delivery and antenatal complications (27.6% vs 43.9%, respectively; P>0.05). CONCLUSION: In this selected population, an elective single embryo transfer policy decreases the multiple pregnancy rate without compromising the live birth rate. The non-significant difference in antenatal complications may be related to the small sample size.

Issues in second trimester induced abortion (medical/surgical methods).

Second trimester abortion remains a common procedure worldwide. Dilatation and evacuation (D&E) is the surgical method of choice, if the surgical expertise and facilities are available. Adequate cervical dilatation preoperatively is a prerequisite for a safe D&E. Medical abortion using misoprostol together with mifepristone is the medical method of choice. The recommended regimen is 200mg mifepristone followed by 800 microg of vaginal misoprostol 36-48 h later. Subsequent doses of 400 microg of misoprostol can be given orally every 3h up to a maximum of four more doses. Proper preoperative assessment would not only help to provide safe abortion treatment, but it also guides the choice of method. If the expertise and facilities of both methods are available, both methods should be discussed and offered to the patient so that the patient can make an informed choice.