A–Z Fertility Glossary

Uterine-lining-like tissue growing into the muscular wall of the uterus.

Antral follicle count — an ultrasound-based estimate of ovarian reserve.

Anti-Müllerian hormone — a blood marker of ovarian reserve.

A specialist in male reproductive health.

The absence of ovulation in a menstrual cycle.

A short IVF stimulation protocol using GnRH antagonists.

Laboratory thinning of the embryo's outer shell.

No sperm present in the ejaculate.

Blood test measuring pregnancy hormone hCG.

An embryo at day 5–6 of development.

A single cell within a cleavage-stage embryo.

Body Mass Index — a rough measure of weight relative to height.

Vaginal secretion produced by the cervix.

An abnormal number or structure of chromosomes.

An oral medication to induce ovulation.

Coenzyme Q10 — a supplement studied in egg and sperm quality.

The structure formed after ovulation that produces progesterone.

Freezing eggs, sperm or embryos for future use.

A cleavage-stage embryo about 3 days after fertilisation.

A hormone sometimes used to support ovarian response.

Lower-than-expected egg supply for age.

An egg from another woman used in IVF.

Sperm from a donor used in fertility treatment.

A pregnancy implanted outside the uterus.

The procedure to collect eggs during IVF.

A fertilised egg during early development.

A visual score for embryo quality.

Placing an embryo into the uterus.

A scientist specialising in embryo development.

Uterine-lining-like tissue growing outside the uterus.

The lining of the uterus.

Endometrial receptivity analysis.

The tube connecting the ovary to the uterus.

Fusion of sperm and egg.

Frozen Embryo Transfer.

A fluid-filled sac in the ovary containing an egg.

Follicle Stimulating Hormone.

Testing DNA to detect inherited conditions.

The first ultrasound-visible sign of pregnancy in the uterus.

Gonadotrophin-Releasing Hormone.

Injectable hormone used in fertility treatment.

Human Chorionic Gonadotrophin.

The UK regulator of fertility treatment.

A medicated frozen embryo transfer protocol.

Hysterosalpingogram — X-ray of the uterus and tubes.

A fluid-filled fallopian tube.

Elevated levels of prolactin.

Excessive ovarian response to stimulation.

Underactive thyroid gland.

Intracytoplasmic Sperm Injection.

ICSI with high-magnification sperm selection.

The embryo embedding into the uterine lining.

Intrauterine Insemination.

In Vitro Fertilisation.

A photographic map of all chromosomes.

A first-line ovulation induction medication.

Luteinising Hormone.

The second half of the menstrual cycle.

Pregnancy loss before 24 weeks.

Shape of sperm.

Movement of sperm.

IVF without ovarian stimulation.

Ovarian Hyperstimulation Syndrome.

An egg cell.

The remaining pool of eggs in the ovaries.

Release of a mature egg from the ovary.

Medication to stimulate ovulation.

Polycystic Ovary Syndrome.

Preimplantation genetic testing for aneuploidy.

Preimplantation genetic testing for monogenic conditions.

Physiologic ICSI using hyaluronic acid binding.

A small gland at the base of the brain.

A hormone that supports the uterine lining.

A pituitary hormone involved in reproduction and lactation.

A test of sperm count, motility and morphology.

Transferring one embryo at a time.

Surgical Sperm Retrieval.

Damage to DNA within sperm.

IVF injectable phase to grow multiple follicles.

The primary male sex hormone.

Blood test measuring thyroid hormones.

Continuous imaging of embryos in the incubator.

Injection that matures eggs before collection.

The outer layer of a blastocyst.

The wait between transfer and pregnancy test.

Serial scans during IVF stimulation.

Infertility with no cause identified on standard tests.

The organ where pregnancy develops.

Enlarged veins in the scrotum.

Ultra-rapid freezing of eggs and embryos.

The outer shell of the egg and early embryo.

A fertilised egg before it divides.