Pre-implantation genetic screening (CGH)
Comprehensive screening of chromosomes in an embryo
Comparative genomic hybridisation (CGH) genetic screening checks chromosomes in an embryo for abnormalities
About CGH screening
Array CGH is a preimplantation genetic screening (PSG) test. It comprehensively screens all chromosomes in an embryo for abnormalities before it is transferred to the womb. Genetically normal embryos have a higher chance of implantation and the resulting pregnancies have a lower chance of miscarriage.
Need to know
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What happens icon plus
The procedure is usually divided into the following steps: Step 1: Assisted reproduction You will have routine IVF or ICSI to produce eggs, which are then collected and fertilised. Step 2: Embryo biopsy When the embryos are five days old, a few cells are removed from each one and sent for testing. The embryos being analysed do not leave the clinic — they are either returned to the incubator or frozen until the test results are available. Step 3: Genetic testing The cells are then analysed independently. The test results show how many copies there are of each chromosome, revealing if there are any abnormal embryos. -
How to prepare icon plus
Your consultant will let you know exactly what happens during the procedure and answer any questions you may have. -
Afterwards icon plus
Your results should be available within 24-36 hours. However, sometimes we can have results for you within four hours. Once genetic testing is complete, we use the results along with standard assessments to help us decide which embryos to transfer to the womb. No test is 100% accurate, so following any genetic screening, we also recommend that you have prenatal testing if you become pregnant.
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This content is intended for general information only and does not replace the need for personal advice from a qualified health professional.