Karyotype Test | Chromosome Analysis Blood Test

A karyotype is a picture of all the chromosomes in a cell, arranged in pairs. To produce it, the laboratory grows living white blood cells from your sample, arrests them while the chromosomes are visible, fixes and stains them, and examines at least 20 cells under the microscope, comparing the banding pattern of each chromosome against the expected pattern at a resolution of 400 to 550 bands. A normal result is written 46,XX for a woman or 46,XY for a man: 46 chromosomes, correctly arranged. Anything else is described precisely using international nomenclature.

Whether you carry a chromosome rearrangement. The important ones for fertility are balanced translocations, where pieces of two chromosomes have swapped places, and inversions, where a segment is reversed, with no genetic material lost or gained. People who carry them are healthy and usually have no idea, but when they make eggs or sperm the rearrangement can produce embryos with too much or too little chromosome material, which fail to implant or miscarry. Around 3 to 5 percent of couples with recurrent miscarriage carry a rearrangement in one partner, several times the rate in the general population.

Healthy couples who have had two or more miscarriages, or have a family history of repeated miscarriage; couples with two or more pregnancies affected by a chromosome condition such as trisomy 21; and couples with two or more failed IVF implantations. It is particularly relevant when the woman is under 35, because age-related egg quality is a less likely explanation. It is normally taken by both partners, since a rearrangement in either can be the cause, and NICE guidance includes karyotyping in the investigation of recurrent miscarriage.

If you have had repeated losses without an explanation, yes: it is one of the few tests that can give a definite cause, and the answer changes what you do next. A rearrangement points towards IVF with genetic testing of embryos, which can avoid further losses, and towards genetic counselling about the chance of recurrence. A normal result rules out that cause and lets your specialist focus on others, such as uterine, hormonal or clotting factors. It is not a test for people without a history of pregnancy loss, and it does not predict whether you will conceive.

Sometimes. NHS recurrent miscarriage clinics may offer parental karyotyping, but in many areas it is done only when a miscarriage has been shown to have an unbalanced chromosome change, and referral usually needs three consecutive losses and can take months. Privately, both partners can be tested after two losses or two failed implantations, without referral, with results in 12 to 14 working days that any NHS or private fertility specialist can use.

£295 per person at a Goodbody clinic or £310 with a nurse home visit, so £590 for a couple in clinic, including the blood draw, laboratory culture and analysis by clinical scientists, the report, and a video consultation with a clinical scientist if a change is found. Private karyotyping in the UK typically costs £250 to £450 per person.

A venous blood sample from each partner, about 4 ml into special tubes that keep the cells alive, taken at a clinic or by a nurse at home. No fasting or timing is needed; drinking water beforehand makes the draw easier. Because the cells must be cultured, the sample is refrigerated and sent to the laboratory the same day and remains viable for up to five days. There are no age or residency restrictions.

12 to 14 working days from the laboratory receiving your sample, because the cells have to be grown before the chromosomes can be examined. Results are emailed to you. Around one in ten samples does not culture successfully and has to be repeated; if that happens, the repeat is free.

A clinical scientist from the laboratory contacts you and arranges a 15 to 30 minute video consultation to explain exactly what has been found and what it means for future pregnancies; your partner or a family member is welcome to join. You receive a full report to share with your GP or fertility consultant, who can arrange genetic counselling and discuss options such as IVF with pre-implantation genetic testing. Results within the expected range are issued by Goodbody with your report.

It looks at the number and structure of chromosomes in the cells analysed. It does not detect changes present in only a proportion of cells, very small or subtle structural changes below its resolution, or differences between tissues. It does not test for single-gene conditions such as cystic fibrosis, does not test the pregnancy itself, and cannot tell you whether you will conceive or carry a pregnancy. A result should always be interpreted alongside your medical history by a clinician.

No. This is a parental karyotype on the couple's own blood. A karyotype or microarray can also be performed on tissue from a miscarriage to find out whether that pregnancy had a chromosome change, and prenatal karyotyping is done on cells from amniocentesis or chorionic villus sampling. If a miscarriage karyotype shows an unbalanced rearrangement, parental testing like this is the next step to find out whether it was inherited.

At any of 250+ Goodbody clinics across the UK, or with a nurse visiting your home so both partners can be tested together. No GP referral is needed. Find your nearest clinic.