Contact Us: 1 300 800 400

Fertility Language

Understanding fertility language - an insight in to the jargon used in fertility treatment.

Most areas of medicine and science have their own jargon and fertility is no exception. The most common terms are listed here. You will probably just skim this section at first and then refer back to it when you want to check out the meaning of an abbreviation or term.

You can also find a comprehensive glossary of terms and abbreviations used in reproduction and fertility treatment, and more information on medications on our Fertility Facts page here.

You may have already encountered some of these abbreviations, but here are some of the more common fertility treatments and the abbreviations used for them:


What this means

Clomiphene A pill usually taken for 5 days early in the menstrual cycle that increases the number of follicles that grow in the ovary. Commonly used in Ovulation Induction.
OI Ovulation Induction is a treatment to induce ovulation in women with irregular or absent cycles.
IUI Intra-Uterine-Insemination is when sperm is placed directly into the uterus.
IVF In Vitro Fertilisation. It strictly means adding sperm and egg together outside the body, but it is usually used to describe the whole process covering medications, egg collection, fertilisation, and embryo transfer.
ICSI Intra-Cytoplasmic Sperm Injection. Surely one of the craziest bits of IVF jargon – it simply means a single sperm is injected into each egg when the sperm cannot do this job themselves.
DS Donor Sperm (formerly called Donor Insemination). Donor sperm can be used with IUI and IVF.
DO Donor Oocyte or donor egg – ‘oocyte’ is the scientific name for an egg. Donor egg is when another woman’s egg is used in an IVF cycle.

IVF treatment has its own set of acronyms and terms:


What this means

Cycle One course of treatment. With IVF, this is from Day 1 through to the pregnancy test.
OPU Oocyte PickUp – also known as egg collection, when the eggs are taken from the ovaries.
ET Embryo Transfer – when the embryo(s) is transferred back into the uterus.
SET Single Embryo Transfer – when only one embryo is transferred into the uterus at a time.
FET Frozen Embryo Transfer. Essentially the defrosting and replacement of an embryo that has been frozen and stored with us after a cycle of IVF. Also known as Thawed Embryo Replacement (TER).
Manufactured cycle An artificial menstrual cycle used to provide the right environment for the transfer of embryos.
Blastocyst The name given to an embryo 5-6 days after fertilisation when it consists of an outer layer of cells that will become the placenta and an inner mass of cells that will become the baby.
SSR Surgical Sperm Retrieval – when sperm are taken directly from the testes using a fine needle.
PESA Percutaneous Epididymal Sperm Aspiration – SSR when sperm are taken from the epididymis, which is a tiny organ sitting on top of the testis.
TESA, TESE Testicular Sperm Aspiration, Testicular Sperm Extraction – other names for SSR.
OHSS Ovarian Hyper-Stimulation Syndrome – a condition that can occur a few days after egg collection that is caused by too many follicles being stimulated to grow at once in the ovaries. Fluid moves from the blood into the abdomen and into tissue. Untreated, it can have serious consequences, including stroke and even death.

Did you know? The eggs in your ovary are smaller than the full stops on this page. The egg develops in a follicle. At the beginning of your menstrual cycle the largest follicles are 4–6mm in diameter - at time of ovulation they are 18–22mm.