As clinical professionals we often lean into our medical language. We don't mean to do it yet caught in the moment it happens! We often overlook the fact that this can be confusing, and many people won't tell us if they don't understand.

So here is an alphabetical list of terms you may hear in an IVF clinic, with a short summary of what they mean. Enjoy this IVF glossary of terms.

A • B • C • D • E • F • G • H • I • L • M • O • P • R • S • T • U • V • Z

A

Abstinence period: The recommended time to abstain from ejaculation before providing a semen sample. This is now widely accepted to be no more then two days.

Adenomyosis: A condition where the inner lining of the uterus breaks through the muscle wall, causing heavy periods, pain and infertility.

Antagonist Protocol: A shorter, more flexible approach that reduces the risk of Ovarian Hyperstimulation Syndrome (OHSS).

Anti-Mullerian Hormone (AMH): A hormone used as a marker to assess ovarian reserve and fertility potential.

Antral Follicle Count: A count of the visible follicles in the ovaries at the beginning of a menstrual cycle, indicating ovarian reserve.

Anti-sperm antibodies: Antibodies that mistakenly attack sperm, reducing their ability to fertilise an egg.

Arrested: A term used to describe embryos that have stopped developing.

Asherman’s Syndrome: A condition where scar tissue forms inside the uterus, often leading to infertility.

Assisted Hatching: A laboratory technique used to help an embryo implant into the uterine lining.

Asthenozoospermia: A condition characterised by reduced sperm motility, affecting the sperm's ability to reach and fertilise an egg.

Azoospermia: A condition where there is no measurable sperm in a man’s semen, leading to infertility.

B

Blastocyst: A stage of embryo development that occurs about five days after fertilisation, when the embryo is ready for implantation.

Blastomere: A cell formed by the division of a fertilized egg during early embryonic development.

Box incubator: An old style incubator that we used to grow embryos in. Its now used to warm meida instead of culture .

C

Congenital bilateral absence of the Vas Deferens (CBVAD): This is when the plumbing/pipe work is not there between the penis and the testicles. Associated with carrying a mutation in one of both of the cystic fibrosis genes.

Carrier Screening: Carrier screening is a genetic test used to determine whether an individual carries a gene for a specific inherited disorder, which could be passed on to their children even if they don't have the condition themselves.

Cavitation: The process during which a fluid-filled cavity forms inside an early-stage embryo, signalling the transition to the blastocyst stage.

Cleavage: The series of cell divisions that occur immediately after fertilisation as the embryo begins to develop.

Clomiphene citrate: A medication used to induce ovulation in women who have trouble ovulating naturally.

Collapsing: A stage where the blastocyst temporarily collapses during the process of embryo development. We can force blastocysts to collapse by using a laser.

Compaction: A stage of embryo development where cells begin to tightly adhere to each other, forming a morula, usually around Day 4

Cryopreservation: The process of freezing biological material, such as embryos or sperm, for future use.

Cumulus Complex: A large ball of cells that the egg is inside and can be visualised at egg collection. It is these cells that provide support in the ovary and assists in the maturation of the egg.

Cytokinesis: The process during cell division where the cytoplasm of a parental cell is divided into two daughter cells.

D

Density/Concentration Gradient: A technique used to separate sperm cells from the semen based on their density for use in fertility treatments.

Dewar: Large tanks, full of liquid nitrogen, where frozen embryos and sperm are stored.

DICSI: An advanced technique in fertility treatment involving intracytoplasmic sperm injection with additional diagnostic tools.

DNA fragmentation: A measure of sperm DNA integrity, with high levels often associated with infertility.

E

Egg collection: A procedure where eggs are retrieved from the ovaries for use in fertility treatments such as IVF.

Embryo: An early stage of development post-fertilisation, before the foetus is formed.

Embryoscope: A timelapse incubator with 16 chambers, created by Vitrolife.

Embryo Transfer (ET): The process of placing an embryo into the uterus during fertility treatment.

Endometriosis: A condition where tissue similar to the lining of the uterus grows outside the uterus, often causing pain and infertility.

Expansion: The stage where the blastocyst increases in size just before implantation.

F

Fertilisation: The process of a sperm cell joining with an egg cell to form an embryo.

Fibroid: Uterine fibroids are non-cancerous growths that develop in the wall of the uterus. They can grow to incredibly large sizes.

Follicle: A small fluid filled sac in the ovary, that increases in size that contains a developing egg.

Follicle Stimulating Hormone (FSH): A hormone that plays a crucial role in the development of eggs in the ovaries.

Fragmentation: The presence of fragments in the embryo, which can indicate poor embryo quality and/or stress.

Freeze all: A strategy in fertility treatment where all viable embryos are frozen for future transfer, rather than immediately transferring them.

Frozen Embryo Transfer (FET): A procedure in which a previously frozen embryo is thawed and transferred into the uterus.

G

Gametes: The reproductive cells (sperm and egg) involved in sexual reproduction.

Geri: A type of timelapse incubator. Each Geri has six chambers. Created by the company Genea.

Germinal Vesicle (GV): The immature stage of an egg cell before it completes the process of maturation.

Gonadotrophin's: Hormones that stimulate the ovaries or testes, often used in fertility treatments to induce ovulation or sperm production.

Gradient: A method used in sperm preparation to separate healthy sperm from debris and less viable sperm.

H

Hatching: The process by which an embryo breaks out of its surrounding zona pellucida (ZP), allowing for implantation into the uterus.

Human Chorionic Gonadotrophin (HCG): A hormone used in fertility treatment to trigger the release of an egg from the ovary.

I

ICSI: Intracytoplasmic sperm injection, a procedure in which a single sperm is injected directly into an egg.

IMSI: Intracytoplasmic morphologically selected sperm injection, a technique where sperm are selected based on detailed imaging before injection.

Inner Cell Mass (ICM): The group of cells inside a blastocyst that will eventually develop into the foetus.

IVF: In vitro fertilisation, a process where an egg is fertilised by sperm outside the body, with the embryo later transferred to the uterus.

L

Liquid Nitrogen: A substance used in cryopreservation to freeze biological material at extremely low temperatures.

Long Protocol: Involves down-regulation before stimulation, ensuring control over ovulation timing, starts in the cycle before the treatment cycle.

Luteal Phase Support: Normally progesterone based medication, that is given after ovulation or embryo transfer to support the uterine lining and increase the chances of pregnancy.

Luteinising Hormone (LH): A hormone that naturally triggers ovulation and is essential in the regulation of the menstrual cycle.

M

Metaphase 1 (Met I): An immature egg that we see in the lab. These can mature in culture.

Metaphase 2 (Met II): A mature egg. This is stage the egg needs to be ready for fertilisation, post-ovulation.

Micromanipulation: Techniques used in the laboratory to manipulate sperm, eggs, or embryos under a microscope, that we call 'the rig' during fertility treatments.

Minc: A bench-top incubator, used commonly, that can encompass low oxygen concentrations and liked due to its small 'footprint'.

Morula: The stage an embryo reaches around day 4. It happens around the 16-32 cell stage and is when all the cells 'meld' together to start the process of differentiation.

Multipolar Division: When one cells directly divides into more than 2 cells. Also called direct 1-3 for example. This type of division can potentially lead to issues with embryo viability and development potential.

O

Oogenesis: The process of egg development in the ovaries. takes approximately 90 days from starting to ovulation.

Oligospermia: A condition characterised by a low sperm count, which can affect fertility.

Ooplasm: The cytoplasm of an egg cell, playing a vital role in embryo development.

Ovarian Stimulation: The use of medication to stimulate the ovaries to produce multiple eggs for retrieval in fertility treatments.

P

PICSI: Physiological intracytoplasmic sperm injection, a technique where sperm are selected based on their ability to bind to hyaluronan, mimicking natural selection.

PIMSI: An advanced sperm selection technique for intracytoplasmic sperm injection, involving detailed imaging and analysis, alongside PICSI.

Pro Nuclei (PNs): The nuclei of the sperm and egg before they fuse to form a single nucleus in a fertilised egg. The number present should only be 2. But ither amounts can occur and still be normal.

Polar Body: A small cell formed alongside the egg during meiosis, containing chromosomes but little cytoplasm. its presence tells us the egg is mature.

Perivitilline Space: The space between the egg cell membrane and the zona pellucida (ZP), playing a role in sperm penetration during fertilisation.

Progesterone: A hormone important for regulating the menstrual cycle and maintaining early pregnancy.

R

Retrograde Ejaculation: A condition where sperm are ejaculated backward into the bladder instead of out of the urethra, potentially causing infertility.

Re-expansion: The stage where a collapsed blastocyst fills with fluid again, often before implantation.

S

Slow freezing: A method of cryopreservation where cells are cooled slowly before being stored at ultra-low temperatures.

Semen: The fluid containing sperm and other secretions, essential for male fertility.

Single Embryo Transfer (SET): A fertility treatment strategy where only one embryo is transferred to reduce the risk of multiple pregnancies.

Spermatogenesis: The process of sperm production in the testes.

Stripping/Denuding: The removal of surrounding cells from an egg before ICSI, allowing better access for sperm injection.

Surgical Sperm Retrieval (SSR): A procedure used to obtain sperm directly from the testes or epididymis in men with azoospermia or other sperm extraction issues.

Swim up: A sperm preparation technique used to select the most motile sperm for use in fertility treatments.

T

Thawing: The process of warming cryopreserved embryos, eggs, or sperm for use in fertility treatments.

Timelapse: A technology used in IVF labs to continuously monitor embryo development, providing insight into embryo viability.

Trigger injection: An injection given to trigger ovulation, typically used in conjunction with fertility treatments.

Trophectoderm: The outer layer of cells in the blastocyst that will form the placenta.

U

Ultrasound: An imaging technique used in fertility treatments to monitor the development of follicles, the uterus, and the embryo.

Utilisation: The process of using embryos, eggs, or sperm in fertility treatment.

V

Vacuole: Fluid filled area that can be linked to embryo development issues and stress.

Vitrification: A rapid freezing technique used in cryopreservation to prevent ice crystal formation and preserve the viability of eggs and embryos, allowing for far higher survival rates than before.

Z

Zona Pellucida (ZP): The outer layer, shell, of the egg that sperm must penetrate to achieve fertilisation.

Zygote: The initial cell formed when a sperm cell fertilises an egg, representing the earliest stage of embryo development.

Zymot: A sperm separation device using a capillary membrane used to isolate the healthiest sperm for use in fertility treatments.

A • B • C • D • E • F • G • H • I • L • M • O • P • R • S • T • U • V • Z

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