C.A.R.E Fertility Clinic Durban and Africa’s first Babies born following Aneuploidy Screening using a Next Generation Sequencing platform.
The C.A.R.E clinic, based in Durban, proudly reports 3 successful cases of Live Birth, all following Preimplantation Genetic Testing for Aneuploidy (PGT-A), using the Next Generation Sequencing (NGS) platform
This patient was a 39 year old woman who presented with primary infertility for 7 years and a previous history of Chondrosarcoma of the left Scapula which was surgically removed and treated at the age of 29 resulting in a full recovery. She also presented with PCOS and her husband witholigospermia.
Pregnancy was achieved after two cycles of IVF treatment. Summary is as follows:
A total of 8 embryos were biopsied on day 5 and screened. Two out of four euploid embryos were transferred and two were frozen. This resulted in the birth of healthylittle baby boy named James, weighing 3.08 kgs and delivered through Caesarean-section.
The second baby was born to a 32 year old woman with an eight year history of Primary infertility. This couple opted to have their embryos screened due the Husband having severe Oligoasthenoteratozoospermia (OAT). A total of 4 embryos were screened using PGT-A. Two euploid embryos were then replaced, followed by a successful pregnancy and live birth of a singleton baby.
PGT-A was executed in view of the severe oligospermia
The third case is a 43 year old lady with a history of infertility & recurrent miscarriages, who was boarded for ICSI and PGT-A. Following standard IVF stimulation and treatment, five eggs were collected and fertilized. Embryo biopsies from each of the hatching embryos were taken on Day 5, and used to screen embryos for chromosomal abnormalities. Two euploid embryos out of 5 were replaced on Day 6 and resulted in the birth of a healthy set of twins. A baby boy weighing 3.1 kg and a baby girl weighing 2.9 kg.
Couples with advanced maternal age benefit from aneuploidy screening especially from 35 years onward. Now that we can analyse all 24 chromosomes, we are able to obtain accurate results in a short space of time. Our three cases demonstrate this well with the added history of recurrent miscarriage.
Studies have revealed that couples with recurrent miscarriage due to aneuploid embryos benefit from the decreased miscarriage rate and increased implantation rate. Severely abnormal sperm can lead to aneuploid miscarriages. Hence, PGT-A can benefit this group of patients. Some studies have shown doubled ongoing pregnancy and implantation rates following PGT-A in both Day 3 and day 5 biopsies.
The first 2 cases highlight the impact of severe sperm factor problems. We are now aware that aberrant sperm can lead to aneuploid embryos – hence, the need for PGT-A in these cases to increase implantation and pregnancy rates. Aneuploidy screening is advised in cases of sperm counts less than 1-2 million and where very poor morphology and motility are observed.
Having used different platforms for PGT-A Screening over the years, we found the NGS platform to be more rapid, reliable and accurate semi-automated system. Also reducing the chance of operator-related errors whilst utilizing a simple workflow.
All in all, NGS has helped increase accuracy of analysis, decrease patient anxiety and increase pregnancy rates. It also allows us to freeze euploid embryos for later use.
All embryos of patients boarded for Aneuploidy Screening were analysed for Mosaicism. The percentage of Mosaicism was low (<50%) for all euploid embryos. This is a very helpful tool when making a clinical decision to transfer, freeze, retest or suggest further testing during pregnancy in the way of Amniocentesis. However, there is room for more in depth studies so that our clinical knowledge can keep up with the latest in research & technology.
The latest NGS also allows full screening of all autosomes, sex chromosomes, subchromosomal aberrations. Embryos with a low mosaicism have a stronger chance of developing into healthy babies than those with higher percentages of Mosaicism (>50%)
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