The words nobody explains

52 entries

Add-onTreatment

An extra test, technique or treatment offered alongside standard IVF, usually at extra cost. Most are optional and their evidence varies a great deal.

AMHAlso called anti-Müllerian hormoneNumbers

A blood test that gives a rough sense of how many eggs the ovaries have left. It says nothing about egg quality and it is not a fertility score or a prediction of whether you can have a baby.

AndrologySperm

The part of the clinic that deals with sperm and male reproductive health, including analysing samples and preparing them for treatment.

AzoospermiaSperm

No sperm found in the ejaculated sample. It does not automatically mean no sperm are being produced, and a specialist will usually investigate further.

BlastocystLab and embryos

An embryo that has kept growing for about five days and reached a more developed stage with two distinct groups of cells. Not every embryo gets this far, and that is common rather than a sign something has gone wrong.

Chemical pregnancyNumbers

A very early pregnancy loss, where a test was positive but the pregnancy stopped before it could be seen on a scan. The clinical name is cold; the loss is real and people are allowed to grieve it.

Clinical pregnancy rateNumbers

The proportion of treatments where a pregnancy is confirmed on a scan. It is always a higher number than live birth rate, because some pregnancies sadly do not continue.Clinics often advertise pregnancy rates rather than live birth rates. If you are comparing figures, ask for live birth rate per embryo transfer, and for your age group.

ConcentrationAlso called sperm countSperm

How many sperm there are in each millilitre of semen. Total count is that figure multiplied by the volume of the sample.

Cumulative success rateNumbers

The chance of a birth across several attempts, for example one egg collection plus every frozen transfer that comes from it. It is a bigger number than a single-attempt rate, so check which one you are being shown.

CycleTreatment

One full attempt at treatment. What a clinic counts as a cycle varies, which matters for both funding and prices, so it is always worth asking exactly what is included.

DNA fragmentationSperm

A test looking at breaks in the genetic material inside sperm. It is not part of standard testing everywhere, and clinics differ on how much weight they give it.

Donor eggsTreatment

Eggs given by another person and used in treatment. In the UK, donors can be identified to any child born once that child turns 18.

Donor spermTreatment

Sperm given by another person and used in treatment. As with egg donation, UK-registered donors are identifiable to the child at 18.

Down-regulationTreatment

A phase where medication quietens your natural hormone cycle first, so the clinic can control the timing of stimulation. Some people get temporary menopause-like side effects during it.

Ectopic pregnancyYour body

A pregnancy that implants outside the womb, most often in a fallopian tube. It cannot continue and it needs urgent medical care.Seek urgent help for one-sided tummy pain, shoulder-tip pain, unusual bleeding or feeling faint. Call your clinic or NHS 111 now, or 999 if you feel very unwell.

Egg collectionAlso called egg retrievalTreatment

A short procedure, usually under sedation, where a fine needle guided by ultrasound draws fluid from the follicles so any eggs can be found. Most people are in and out the same day and sore for a day or two.

EmbryoLab and embryos

What an egg becomes once it has been fertilised by sperm and starts dividing into more cells. Embryos are watched in the lab for a few days to see which are developing well.

Embryo transferTreatment

An embryo is passed through a thin soft tube into the womb. It usually takes a few minutes, feels similar to a smear test, and does not need sedation.

EmbryologyLab and embryos

The lab side of IVF. Embryologists handle the eggs, sperm and embryos, decide day to day how they are developing, and are often the people who ring you with updates.

Endometrial liningYour body

The everyday name for the endometrium and its thickness on a scan, usually given in millimetres. Clinics look at it before deciding whether to go ahead with a transfer.

EndometriumYour body

The lining of the womb. It thickens across a cycle so an embryo has somewhere to settle, and it is what is being measured when a scan mentions your lining.

FETAlso called frozen embryo transferTreatment

Transferring an embryo that was frozen in an earlier cycle and then thawed. It usually costs less than a full cycle because there is no stimulation or egg collection involved.

FollicleYour body

A small fluid-filled sac in the ovary. Each one may contain an egg. Scans during treatment count and measure follicles to see how the ovaries are responding.

Freeze-allTreatment

A plan where every suitable embryo is frozen and none are transferred in the same cycle as egg collection. Clinics may suggest it for various reasons, including giving the body time to settle after stimulation.

Fresh transferTreatment

An embryo transfer that happens a few days after egg collection, in the same cycle, without freezing the embryo first.

FSHAlso called follicle stimulating hormoneNumbers

A hormone that tells the ovaries to ripen eggs. It is measured in blood tests and also given as a medication during stimulation.

HFEAAlso called Human Fertilisation and Embryology AuthorityWho's who

The UK regulator for fertility clinics. It licenses and inspects clinics, publishes independent information for patients, and rates the evidence behind treatment add-ons.

ICBAlso called Integrated Care BoardWho's who

The NHS organisation that plans and pays for healthcare in a local area of England. Your local ICB decides who can get NHS-funded IVF where you live, and the rules differ between areas.

ICSIAlso called intracytoplasmic sperm injectionTreatment

A version of IVF where an embryologist injects a single sperm directly into each egg, rather than letting sperm and egg meet in the dish. It was developed for couples where the sperm is the main difficulty.Very widely used, including for couples with no sperm problem. See the add-ons page for what the evidence generally says.

ImplantationYour body

When an embryo attaches to the lining of the womb and starts to establish a pregnancy. It cannot be seen or felt, and no test can tell you it is happening in real time.

IUIAlso called intrauterine inseminationTreatment

A simpler and cheaper treatment than IVF. Prepared sperm is placed directly into the womb around the time an egg is released. Nothing happens in a lab dish and no eggs are collected.

IVFAlso called in vitro fertilisationTreatment

Eggs are collected from the ovaries and mixed with sperm in a lab dish so fertilisation can happen outside the body. If an embryo develops, it is placed into the womb a few days later. One full round of this is called a cycle.

LHAlso called luteinising hormoneNumbers

A hormone involved in releasing a mature egg. During treatment clinics watch it closely because an early rise can affect when eggs are collected.

Live birth rateNumbers

The proportion of treatments that end with a baby born alive. This is the number that answers the question most people are actually asking.

Long protocolTreatment

A treatment plan that starts with down-regulation before stimulation begins, so it runs over roughly four weeks or more.

Male factor infertilitySperm

When something about the sperm is a contributing reason a couple has not conceived. It plays a part in roughly half of cases, on its own or alongside other factors.

MiscarriageYour body

The loss of a pregnancy before 24 weeks. It is common, it is not caused by anything you did, and your clinic or GP can advise on what happens next.Contact your clinic, GP or NHS 111 about bleeding or pain in early pregnancy, and 999 if bleeding is heavy or pain is severe.

MorphologySperm

The shape and structure of sperm. It is normal for most sperm in any sample to be an unusual shape, so a low percentage here is not the alarming result it sounds like.

MotilitySperm

How well sperm swim. Labs look at what proportion are moving and how many are moving forwards rather than in circles or on the spot.

NICEAlso called National Institute for Health and Care ExcellenceWho's who

The body that writes national guidance on what the NHS should offer. Its fertility guidance is a recommendation, not a rule, which is part of why funding varies so much.

OestradiolAlso called estradiol, E2Numbers

A form of oestrogen measured in blood tests during stimulation. Rising levels generally track with follicles growing, which is why it is checked alongside scans.

OHSSAlso called ovarian hyperstimulation syndromeYour body

A reaction to fertility drugs where the ovaries swell and fluid can build up in the abdomen. Mild forms are fairly common; severe forms are uncommon but are a medical emergency.Contact your clinic straight away about severe abdominal pain, rapid swelling, breathlessness, vomiting, or much less urine than usual. Out of hours, call NHS 111, or 999 if it is severe.

Ovarian stimulationAlso called stimsTreatment

The part of a cycle where daily injections encourage the ovaries to ripen several eggs at once instead of the usual one. It normally lasts around ten to fourteen days with regular scans and blood tests.

PGSLab and embryos

The older name for PGT-A. If a clinic uses either term they mean the same kind of chromosome screening of embryos.

PGT-AAlso called preimplantation genetic testing for aneuploidy, PGSLab and embryos

A test where a few cells are taken from an embryo to check whether it has the expected number of chromosomes. Embryos that test as abnormal are usually not transferred.

Secondary infertilityTreatment

Difficulty conceiving after already having a child. It can be just as hard, and it often affects NHS funding, since many areas only fund treatment for couples with no children.

Short protocolAlso called antagonist protocolTreatment

A shorter plan that skips the down-regulation phase and adds a medication partway through stimulation to stop eggs being released too early. It usually takes around two weeks.

Sperm analysisAlso called semen analysisSperm

A lab look at a semen sample, mainly measuring how many sperm there are, how well they move and what shape they are. Results move about a lot between samples, so one result on its own is rarely the whole picture.

SurrogacyTreatment

An arrangement where another person carries a pregnancy for you. In the UK it is legal but cannot be paid for beyond reasonable expenses, and parenthood has to be transferred by a court order after the birth.

Trigger shotTreatment

A final injection given at a precise time to bring the eggs to full maturity before collection. The timing is exact because egg collection is booked for a set number of hours afterwards.

Two week waitAlso called 2wwTreatment

The stretch of roughly two weeks between an embryo transfer and the pregnancy test. Almost everyone finds it the hardest part, and there is nothing you can do in it to change the outcome.

Unexplained infertilityTreatment

The label used when standard tests come back normal and no clear cause is found. It means the tests did not find a reason, not that there is no reason.

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