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Fertility Glossary

297 fertility and IVF terms explained in clear, patient-friendly language. Search or browse by category.

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Anatomy (24) ▸

Cervical canal: The narrow passageway leading from the vagina into the uterus.
Cervical mucus: The substance in the cervix through which sperm must swim to enter the uterus.
Cervix: The lower, narrow end of the uterus (entrance or neck of the womb) that connects the uterine cavity to the vagina.
Corpus luteum: Means "yellow body" in Latin; a structure that forms in the ovary after a mature follicle releases its egg during ovulation. The corpus luteum produces estrogen and progesterone hormones, which help prepare the lining of the uterus (endometrium) for a potential pregnancy.
Endometrium: The inside lining of the uterus that is shed each month during a period.
Fallopian tubes (aka "tubes"): A pair of hollow tubes attached on each side of the uterus, through which the egg travels from the ovary, through the fimbriae, to the uterus. Fertilization usually occurs in the Fallopian tube during natural conception, before the fertilized egg travels down to the uterus to implant. The fallopian tube is the most common site of ectopic pregnancy.
Fimbriae: The fern-like ends of the fallopian tubes, near the ovaries.
Follicle: The part of the ovary where the egg develops.
Hypothalamus: A small structure at the base of the brain which regulates body functions such as temperature and appetite.
Ovaries: A pair of organs (each about the size of an almond) in a woman’s pelvis. They produce follicles from which eggs develop.
Ovulation: The process by which the ovaries produce and release an egg each month. Ovulation usually takes place around 10–16 days before a period.
Pelvis: The bony structure at the lower part of the abdomen.
Peritoneum: The tissue that lines the abdominal wall and covers most of the organs in the abdomen.
Pituitary gland: A gland in the brain that produces hormones.
Placenta: An organ which develops in the womb linking the baby with the mother’s system. It is delivered after the baby, when it is known as the afterbirth.
Polycystic ovaries: Ovaries which develop too many follicles (vs normal ovaries) in the early part of the menstrual cycle.
Reproductive organs: The parts of the male and female body needed to create and sustain a pregnancy.
Semen: The fluid that contains sperm.
Sperm: The male reproductive cell which fertilises a woman’s eggs. Men usually have millions of sperm in their semen.
Transvaginal scan: A scan where the probe is placed inside the vagina.
Urethra: The tube through which urine empties out of the bladder.
Uterus or womb: The organ where a baby develops during pregnancy. Made of muscle, it is hollow, stretchy and about the size and shape of an upside-down pear. It sits between the bladder and the rectum in a woman’s pelvis.
Vagina: The canal leading from the vulva to the cervix.
Vaginal discharge: Any vaginal secretion except menstrual bleeding.
Vas deferens: The tube which carries sperm from the testicles to the penis.
Vulva: The area surrounding the opening of the vagina. It includes the inner and outer vaginal lips (the labia) and the clitoris.

Conditions (62) ▸

Adrenal hyperplasia: A condition where the adrenal glands produce too many male hormones, called androgens. This happens because of a genetic issue.
Amenorhea: Absence of menstrual periods
Anovulation: Lack of ovulation
Anti-beta-2 glycoprotein antibodies: Antibodies tested as part of an antiphospholipid syndrome panel. Their presence can increase the risk of blood clots, recurrent miscarriage, and implantation failure.
Antiphospholipid syndrome: A condition caused by your immune system mistakenly attacking healthy cells in your body. It can increase your risk of blood clots and of pregnancy complications such as recurrent miscarriage or stillbirth
Appendicitis: A condition where the appendix (a tubular structure attached to the large colon) becomes infected and inflamed and can be associated with the formation of adhesions near the fallopian tube.
Azoospermia: The complete absence of sperm in the semen. It can be obstructive (a blockage preventing sperm from reaching the semen) or non-obstructive (the testes are not producing sperm).
Biochemical pregnancy or chemical pregnancy (aka "chemical"): A very early pregnancy loss that occurs shortly after implantation, detected only by a positive pregnancy test (hCG) before anything is visible on ultrasound.
Blighted ovum: Also called an anembryonic pregnancy. A fertilised egg implants in the uterus and a gestational sac forms, but the embryo does not develop. It is a common cause of early miscarriage.
Chlamydia (trachomatis): A sexually transmitted infection which can damage the reproductive system of both men and women if it is not treated promptly. Chlamydia is treated with antibiotics. Both partners require treatment.
Depression: A common mental health condition, which is characterised by low mood or loss of pleasure or interest in activities for long periods of time.
Diabetes: A condition caused by high levels of glucose (a form of sugar) in the blood. The amount of glucose in your blood is controlled by a hormone called insulin. There are 2 types, Diabetetes Type 1 and Type 2.
DOR - Diminished Ovarian Reserve: A condition in which a woman has fewer eggs remaining than expected for her age. It may require more aggressive fertility treatment or higher medication doses.
DVT - Deep vein thrombosis: A blood clot that forms in a deep vein.
Dysmenorrhoea: Painful menstrual cramps. Sometimes a symptom of endometriosis.
Dyspareunia: Pelvic or genital pain that can be experienced before, during, or after intercourse. Sometimes a symptom of endometriosis.
Early miscarriage: When a woman loses her baby in the first three months of pregnancy.
Ectopic pregnancy: A pregnancy that implants outside of the uterus, usually in one of the fallopian tubes. This tube may rupture or bleed as the pregnancy grows and create or result in a serious medical situation.
Endometrioma or "chocolate cyst": A cyst in the ovary filled with blood and endometrial tissue that occurs in some individuals with endometriosis.
Endometriosis: A condition where tissue resembling endometrium (the inside lining of the uterus) grows outside the uterus; can be found anywhere, but usually around the the other organs in the pelvis. It may cause pelvic pain and is often associated with infertility.
Endometritis (aka chronic endometritis): Inflammation of the endometrium caused by pathogens (most often bacterial invasion). Can cause RIF and RPL. May sometimes cause discomfort or pain.
Factor V Leiden: A common inherited genetic mutation that increases the tendency for blood to clot. It is tested in recurrent pregnancy loss workups as it may contribute to miscarriage.
Fibroids: Non-cancerous growths that develop in the muscle (myometrium) of the uterus. A woman can have one fibroid or many, and they can be of different sizes. Fibroids are sometimes known as uterine myomas or leiomyomas.
Gonorrhoea: A sexually transmitted infection caused by the bacteria Neisseria gonorrhoea or gonococcus. It is treated with antibiotics, and can cause long lasting damage in both partners if left untreated.
Herpes: A family of viruses which cause a range of infections including chickenpox (Herpes zoster, or varicella), cold sores and genital herpes (Herpes simplex).
Heterotopic pregnancy: A rare condition in which two pregnancies occur simultaneously — one inside the uterus and one outside (usually in a fallopian tube). It is more common in IVF pregnancies.
HPV - Human papillomavirus: A common virus that most men and women will have at some point in their life. In most people, HPV will go away by itself without causing problems. A few types of HPV can cause cell changes that may develop into cancer.
Hyperprolactinaemia: A disorder which increases the normal level of the hormone prolactin. It can cause irregular periods and fertility problems.
Hypertension: Raised blood pressure.
Hypotension: Low blood pressure.
IBS - Irritable bowel syndrome: A chronic disorder involving abdominal pain, bloating and changes in bowel habits, such as diarrhea. It is caused by an overactive bowel.
Incomplete miscarriage: When a miscarriage has started but some tissue remains in the uterus.
Infectious: Conditions which can be passed from person to person by micro-organisms like viruses or bacteria.
Late miscarriage: The unplanned loss of a pregnancy after 13 and before 23 weeks.
Lupus anticoagulant: An antibody associated with antiphospholipid syndrome that increases the risk of blood clots and pregnancy complications. Despite its name, it actually promotes clotting rather than preventing it. Not necessarily related to Lupus.
Miscarriage: The unplanned loss of a pregnancy before 23 weeks.
Missed miscarriage (aka delayed miscarriage or silent miscarriage): A pregnancy loss in which the embryo has stopped developing but has not been expelled from the uterus. Often discovered during a routine ultrasound.
Molar pregnancy: A rare condition where the placenta overgrows and the embryo does not form correctly.
OHSS - Ovarian hyperstimulation syndrome: A potentially serious complication of fertility treatment, particularly of IVF. Symptoms are abdominal swelling or bloating, nausea and vomiting.
Oligospermia: A lower-than-normal sperm count in the semen (fewer than 15 million sperm per millilitre). It can reduce the chances of natural conception.
PAI-1 - Plasminogen Activator Inhibitor-1: A protein involved in blood clotting regulation. Certain mutations in the PAI-1 gene may be associated with recurrent pregnancy loss and implantation issues.
PCOS - Polycystic ovary syndrome: A condition which can affect a woman’s menstrual cycle, fertility, hormones and aspects of her appearance, and sometimes long-term health. It is a common hormonal disorder affecting 5-10% of women of reproductive age, characterized by irregular periods, high androgen levels (causing acne/hirsutism), and, often, enlarged ovaries with small cysts.
Pelvic congestion: Swollen pelvic veins.
Pelvic pain: Pain in the lower abdomen or pelvis.
PID - Pelvic inflammatory disease: An infection in the womb, fallopian tubes and/or pelvis caused by infections such as chlamydia and gonorrhoea.
POI - Premature Ovarian Insufficiency: A condition where the ovaries stop functioning normally before age 40, leading to irregular or absent periods and reduced fertility. Previously known as premature ovarian failure.
Polyp: A growth of tissue arising from the lining layer of an organ of your body. Polyps can grow in many different places, for example, cervix, uterus, bowel, inside of nose, skin.
Recurrent miscarriage: When a woman loses three or more babies before 23 completed weeks.
RIF - Recurrent Implantation Failure: When embryos fail to implant after multiple IVF transfer attempts (typically three or more), prompting investigation into uterine, immunological, or embryo-related causes.
RPL - Recurrent Pregnancy Loss: The loss of two or more pregnancies. Investigation may include genetic, hormonal, anatomical, and immunological testing.
SCH - Subchorionic hematoma: A collection of blood between the uterine wall and the gestational sac. It can cause bleeding in early pregnancy and is usually monitored by ultrasound. Many resolve on their own.
Sterilisation: Permanent contraception for women (see tubal occlusion) and men (see vasectomy).
STI - Sexually transmitted infection: An infection that is passed on through close physical contact during sex. Some STIs have no symptoms, so it is important to be tested if you think you have been at risk. See also chlamydia, genital herpes and HIV.
Thrombophilia: A blood clotting abnormality which tends to run in families, whereby the blood is more likely to clot than usual.
Thrombosis: A clot in a blood vessel.
Vaginal discharge (abnormal): An abnormal smelling yellow or green discharge which should be assessed by a doctor.
Vaginal discharge (normal): A clear or whitish fluid that comes from the vagina or cervix.
Vaginal thrush (aka Candida albicans): An infection caused by a yeast known as Candida albicans. Symptoms include redness and itching around the genital area and unusual vaginal discharge.
Varicocele: An enlargement of the veins within the scrotum, similar to varicose veins. Varicoceles can raise testicular temperature and impair sperm production and quality. They are one of the most common treatable causes of male infertility.
Vasectomy: A permanent method of contraception for men. It blocks, seals or cuts the tube (the vas deferens) which carries sperm from the testicles to the penis. Also known as sterilisation.
Venous thrombosis: A blood clot that forms in a vein.
Yeast infection (aka BV or Bacterial vaginosis): A very common vaginal infection which results in discharge and soreness (commonly called "yeast infection". It is caused by an imbalance in the types of bacteria in the vagina. It is not sexually transmitted and does not affect men.

Embryology (21) ▸

Arrested embryo: An embryo that has stopped developing and is no longer viable. Embryo arrest can occur at any stage and may be due to chromosomal abnormalities or other factors.
Blastocyst grading: A scoring system for day 5-6-7 embryos based on expansion (1–6), inner cell mass quality (A–C), and trophectoderm quality (A–C). For example, a 4AA blastocyst is fully expanded with excellent ICM and trophectoderm.
Calcium ionophore: A laboratory treatment applied to eggs during ICSI to help trigger the fertilisation process. Used in cases of previous total fertilisation failure or very low fertilisation rates.
Compaction: The stage of embryo development (typically day 3–4) when individual cells merge together tightly, forming a compact mass called a morula before becoming a blastocyst.
Cryopreservation: The process of freezing and storing eggs, sperm, or embryos at extremely low temperatures to be used at a later date.
DE - Donor egg: An egg from a fertile individual is donated to an infertile individual to be used in an assisted reproductive technology procedure such as IVF. The individual receiving the egg will not be genetically related to the child but will be the birth mother.
Dizygotic: Di - two; zygote - fertilized egg. Two separate eggs fertilized by separate sperm in a single pregnancy. Fraternal twins.
Donor sperm: Sperm given by a male (donor) who is not the recipient's partner.
Egg (oocyte): A female reproductive cell, commonly known as an "egg", produced and released by the ovaries. When fertilized by sperm, it forms an embryo.
Egg donation or Oocyte donation: A process where a woman donates her eggs (oocytes) to help another person or couple conceive. The donated eggs are fertilized by sperm outside the body. The resulting embryos are then transferred to the recipient's uterus with the aim of achieving pregnancy.
Egg quality: A term describing the health and chromosomal normality of a woman's eggs. Egg quality declines with age and is a key factor in fertility and IVF success rates.
Embryo: The early stage of development after an egg, fertilized by sperm, begins dividing and growing.
Embryo culture: Growth and monitoring of embryos, formed by fertilizing eggs with sperm, in a specialized incubator outside the body. These incubators can support embryos’ development for up to 7 days, after which embryos can be transferred to the uterus or frozen for future use.
Embryo grading: A system used by embryologists to assess embryo quality based on cell number, fragmentation, and symmetry (for day 3 embryos) or expansion, inner cell mass, and trophectoderm quality (for blastocysts).
Hatching: The natural process by which a blastocyst breaks out of its zona pellucida (outer shell) so it can implant into the uterine lining. See also assisted hatching.
ICM - Inner cell mass: The cluster of cells inside a blastocyst that will develop into the fetus. ICM quality is one of the factors assessed during blastocyst grading.
ICSI - Intracytoplasmic sperm injection: A form of assisted conception in which a single sperm is injected into an egg.
Morula: An early-stage embryo (typically day 3–4 after fertilisation) consisting of a compact ball of cells, before it develops into a blastocyst.
TE - Trophectoderm: The outer layer of cells in a blastocyst that will form the placenta. Trophectoderm quality is assessed during blastocyst grading and is the part biopsied for PGT.
Vitrification: An ultra-rapid freezing technique used to cryopreserve eggs, sperm, or embryos. It prevents ice crystal formation, resulting in high survival rates upon thawing.
Zona pellucida (or "zona"): The protective outer shell surrounding an egg and early embryo. Sperm must penetrate the zona pellucida to fertilise the egg, and the embryo must hatch out of it to implant.

General (60) ▸

Adenomyosis: When tissue from the lining of the uterus (endometrium) grows into the muscular wall of the uterus. It's not cancerous, but it can cause painful or heavy periods.
Adhesions: Bands of fibrous scar tissue that may bind the pelvic organs and/or loops of bowel together. Adhesions can result from previous infections, endometriosis, or previous surgeries.
AFC - Antral follicle count: The number of small fluid-filled follicles (see the definition of follicle, ovarian below) in the ovaries observed using ultrasound
Anaesthesia: Using medications to stop you feeling sensations, such as pain. This ranges from numbing small parts of the body using injections (local anaesthetic) to putting you to sleep for a procedure or operation (general anaesthesia).
Antibody: Blood protein that helps fight attacks on the immune system, such as those caused by bacteria and viruses.
Autoimmune response: When the body produces antibodies which react against the body’s own tissues.
Beta (beta hCG blood test): A blood test measuring the level of human chorionic gonadotropin (hCG) to confirm pregnancy after fertility treatment. Usually done about 9–14 days after embryo transfer.
BFN - Big Fat Negative: Informal term used in the fertility community for a negative pregnancy test result.
BFP - Big Fat Positive: Informal term used in the fertility community for a positive pregnancy test result.
Bicornuate uterus (womb): A unusually shaped uterus, in a heart shape (usually the uterus would be pear-shaped)
Blastocyst: An embryo that has progressed and started to form the early placenta and a fluid-filled cavity, usually 5 to 6 days after ovulation or egg retrieval.
BMI - Body mass index: A measurement to work out the range of healthy weights for a person. It is calculated by dividing your weight (in kilograms) by your height (in metres squared – that is, your height in metres multiplied by itself). The healthy range is between 19 and 25.
Cervical screening: An internal swab test to check your cervix is healthy. It is sometimes called a smear test.
Chronic: Something that persists or continues for at least six months.
Clinical pregnancy: A pregnancy confirmed by an increasing level of hCG and the presence of a gestational sac detected by ultrasound.
Complete miscarriage: When all the tissue associated with a pregnancy has gone and the uterus is empty.
Conception: When an egg is fertilised by sperm and then starts to grow in the womb.
Congenital: A trait that is present at birth.
Contraception: Contraception, or birth control, is what you and your partner can use to help prevent an unwanted pregnancy or to space out your pregnancies. There are many different forms of contraception including condoms, hormonal pills and implants, hormonal and non-hormonal coils and permanent methods such as female sterilization or vasectomy. You can get more information about contraception from your GP or a family planning clinic.
Diagnosis: The way a medical professional recognises a condition or disease.
DPO - Days Past Ovulation: A way of counting the days after ovulation has occurred, commonly used when tracking early pregnancy symptoms or timing a pregnancy test.
Early menopause: Also called premature ovarian failure. When menstrual periods stop before the age of 40 due to ovaries not working properly.
Endocrinologist: A physician who specializes in endocrinology, which is the medical specialty concerned with hormones and their actions
Endometrial microbiome: The community of microorganisms living in the uterine lining. Research suggests that the balance of bacteria — particularly the presence of Lactobacillus — may influence implantation success.
Fertilisation: When a sperm enters an egg and an embryo forms. Natural fertilisation takes place inside a woman’s fallopian tubes. It can also take place outside the body, which is known as assisted conception. Techniques include IVF. See IVF and ART.
Fertility: The ability to conceive a baby and, for a woman, to become pregnant.
Fertility drugs: Treatment to encourage the ovaries to produce one or several egg(s). It is used during treatment for infertility.
Folic acid: A B vitamin which reduces the risk of a baby being born with a spinal defect such as spina bifida. Ideally, a woman should take folic acid (400 micrograms) 3 months before conceiving. All women should take it for the first 12 weeks of pregnancy. A higher dosage (5 mg) is recommended if you are overweight, on epilepsy treatment, are diabetic or are having twin/triplets.
Follicular phase: The first half of the menstrual cycle, from the start of a period to ovulation, during which follicles develop in the ovaries under the influence of FSH.
Gene: A biological unit which passes on inherited information from parent to child, like facial characteristics.
Genetic counselling: Discussions with a specialist to help you decide what to do if you, your partner or a close relative is found to carry an inheritable disease.
Genitals: The sexual organs: in a woman, the vagina and vulva; and in a man, the penis and testicles.
Hormone treatment: The use of hormones to treat disease or to replace hormones no longer produced by the body.
Hormones: Naturally occurring substances made in the body which control the activity of normal cells. They include: follicle stimulating hormone, gonadotrophins, human chorionic gonadotrophin, luteinising hormone, estrogen, progesterone, prostaglandin.
HRT - Hormone replacement therapy: It is the use of hormones to treat symptoms related to low levels of hormones in the body.
IgG - Immunoglobulin Gamma: A natural substance in the blood that protects against disease and infection. It is also used as a drug to boost immunity.
Immune system: The way the body defends itself against infection, disease and outside substances.
Immunological implantation dysfunction: A theory that an abnormal immune response in the uterus may prevent embryo implantation. Proposed treatments include intralipids, IVIG, and corticosteroids, though evidence remains debated.
Implantation: The process through which an embryo attaches to the lining of the womb.
Infertility (aka fertility problem or subfertility): When a couple fail to conceive after having regular sexual intercourse for more than a year. ‘Regular’ is defined as two or three times a week.
Inflammation: A bodily response in which white blood cells and other immune cell protect your body from disease or injury.
IUD - Intrauterine device: A small device fitted into the womb to prevent conception. Made of plastic and copper, it has one or two soft threads at the end which emerge through the cervix into the top of the vagina.
Libido: Sexual desire.
Luteal phase: The second half of the menstrual cycle, from ovulation to the start of the next period. That is when the corpus luteum produces progesterone to support a potential pregnancy.
Menopause: The time when a woman’s periods stop, usually around 50 years of age. See also menstrual cycle.
Menstrual cycle: The monthly process during which an egg develops and the lining of the womb is prepared for possible pregnancy. If the egg is not fertilised, it is reabsorbed back into the body and the lining of the womb (the endometrium) is shed. This is known as a period or menstruation. The cycle is controlled by hormones and on average a cycle lasts 28 days.
Metabolism: This involves chemical reactions to generate energy for organs to work. It is a complex mechanism leading to making compounds such as proteins, fats, and sugars. This involves processes to remove by-products and is affected by many variables within the same individual and amongst different individuals.
MRI - Magnetic Resonance Imaging: A non-invasive imaging technique using magnetic fields and radio waves to produce detailed images of the body. Used in fertility to evaluate uterine abnormalities, fibroids, adenomyosis, and endometriosis.
Multiple pregnancy: When a woman is carrying more than one baby, e.g. twins or triplets.
NK cells - Natural Killer cells: A type of immune cell found in the blood and uterine lining. Elevated or abnormal NK cell activity has been studied as a possible factor in recurrent implantation failure and miscarriage, though this remains an area of active research.
Period (aka menses): A bleed from the vagina between every 3 to 5 weeks which forms part of the menstrual cycle (see menstrual cycle).
Pregnancy test: A test on a sample of urine or blood to confirm whether a woman is pregnant. The test works by detecting the presence of a pregnancy hormone.
Preimplantation factor (PIF): A peptide secreted by viable embryos that plays a role in immune regulation and implantation. Research into PIF is ongoing and may lead to new ways of assessing embryo viability.
RE - Reproductive Endocrinologist: A doctor who specialises in diagnosing and treating infertility and reproductive hormonal disorders. REs are the primary physicians overseeing IVF and other fertility treatments.
Reproductive immunology: A subspecialty that studies how the immune system affects fertility, implantation, and pregnancy maintenance. It investigates conditions like elevated NK cells, autoimmune factors, and immunological implantation dysfunction.
Reproductive years: In women, the time from the start of menstrual periods (menarche) to the menopause.
Th1/Th2 ratio: A measure of the balance between two types of immune responses. An elevated Th1/Th2 ratio has been proposed as a factor in recurrent implantation failure, though this testing is not universally accepted.
TWW - Two Week Wait: The roughly two-week period between embryo transfer (or ovulation) and the pregnancy test. A notoriously anxious time for fertility patients.
Ultrasound: High-frequency sound waves used to provide images of the body, tissues and internal organs.
WHO - World Health Organization: The United Nations agency responsible for international public health. WHO sets reference values for semen analysis and guidelines for reproductive health.

Genetics (11) ▸

Chromosomal abnormality: A different number or arrangement of chromosomes from the usual pattern.
Chromosomes: The genetic structures within cells which contain our DNA (the material that carries genetic information). Humans typically have 23 pairs of chromosomes (A normal cell contains 46 chromosomes sorted out in 23 pairs). Two of the 46 are the sex chromosomes, the X and Y chromosomes. Usually, females have two X chromosomes, and males have one X and one Y chromosome.
DNA - Deoxyribonucleic Acid: The molecule that carries genetic instructions for the development and functioning of living organisms. DNA is found in chromosomes and determines inherited traits.
Down Syndrome: A genetic disorder caused by the presence of an extra chromosome 21. Individuals with this condition often have intellectual disabilities, physical differences, and medical problems such as heart defects.
HLA - Human Leukocyte Antigen: Proteins on the surface of cells that help the immune system distinguish the body's own cells from foreign ones. HLA testing may be performed in couples with recurrent pregnancy loss.
Karyotype: A record of the complete set of your chromosomes.
Karyotyping: A procedure to produce a karyotype using a blood or tissue sample. It is used to check for abnormalities in the chromosomes.
MTHFR mutation: A genetic variation in the MTHFR gene that affects how the body processes folate. Some studies have linked certain MTHFR variants to recurrent pregnancy loss, though routine testing remains controversial.
PGT-A - Preimplantation Genetic Testing for Aneuploidies: Genetic testing performed on embryo biopsies to screen for an abnormal number of chromosomes. Helps select chromosomally normal embryos for transfer, improving IVF success rates.
PGT-M - Preimplantation Genetic Testing for Monogenic Disorders: Genetic testing of embryos for a specific inherited single-gene disorder (e.g., cystic fibrosis, sickle cell disease) before transfer.
PGT-SR - Preimplantation Genetic Testing for Structural Rearrangements: Genetic testing of embryos to detect chromosomal structural changes such as translocations or inversions that a parent may carry.

Hormones (17) ▸

Adrenal glands: Glands located above each kidney that secrete a large variety of hormones (cortisol, adrenaline, and others) that help the body withstand stress and regulate metabolism. Altered function of these glands can disrupt menstruation, cause inappropriate hair growth, and affect blood pressure.
AMH - Anti-müllerian hormone: A hormone which is often measured in a woman to help determine her egg supply, or "ovarian reserve". It is secreted by small, growing follicles.
Androgen: In men, androgens are the “male” hormones produced by the testes which are responsible for encouraging masculine characteristics and supporting sperm production. In women, androgens are produced in small amounts by both the adrenal glands and ovaries. In women, excess amounts of androgens can lead to irregular menstrual periods, obesity, excessive growth of body hair (hirsutism), and infertility.
Cortisol: A hormone made by the adrenal glands, found on top of the kidneys near the back's waistline. It helps regulate the body's energy levels, blood sugar, and response to stress.
DHEA - Dehydroepiandrosterone: A hormone naturally made by the adrenal glands. The body turns it into other hormones such as estrogen and testosterone. DHEA sold as a “natural” supplement is made from plant chemicals and is not regulated by the FDA. It often is marketed as an antiaging medication, but its safety and effectiveness are controversial.
Estrogen or Oestrogen: Female sex hormones made by the ovaries, which help develop female sex traits. During a natural cycle, estrogens encourage an egg to mature and help the lining of the uterus grow. Levels vary during the menstrual cycle. Estrogens also play a role in keeping bones healthy and overall female well-being. Males also produce a bit of these hormones when testosterone changes into estrogen.
FSH - Follicle-stimulating hormone: Hormones which help the development of follicles during a woman’s menstrual cycle and regulate sperm and hormone function in men.
GnRH agonist - Gonadotrophin-releasing hormone agonist: A synthetic hormone-like drug which holds back the production of eggs.
Gonadotrophins: A class of hormones that stimulate the ovaries and testes. The main gonadotropins used in fertility treatment are FSH (follicle-stimulating hormone), LH (luteinising hormone), and hMG (human menopausal gonadotropin).
hCG - human Chorionic Gonadotrophin: A hormone made by the placenta which shows up in a woman’s blood or urine if she is pregnant. May be used as part of assisted conception to help eggs to mature and to help an embryo attach to the womb.
hMG - Human Menopausal Gonadotropin: An injectable fertility medication containing both FSH and LH, derived from purified urine of postmenopausal women. Used to stimulate egg development during IVF or ovulation induction cycles.
LH - Luteinising hormone: A natural hormone released during the menstrual cycle to help stimulate ovulation.
Progesterone: A hormone produced as a result of ovulation. It prepares the lining of the womb to enable a fertilised egg to implant there.
Progestogen: A synthetic hormone, similar to progesterone. It thickens the mucus around the cervix, making it difficult for sperm to get into the womb or for a fertilised egg to implant in the womb.
Prolactin: The hormone which is responsible for producing breast milk.
Prostaglandin: The hormone that makes the womb contract during labour. Synthetic prostaglandins can be used to induce labour or in medical abortion to end a pregnancy.
Testosterone: A male hormone that occurs in small amounts in women and can be used as a part of hormone replacement therapy

Infertility Treatment (41) ▸

ALICE test: A molecular test that detects bacteria associated with chronic endometritis (infection of the uterine lining). Identifying and treating these infections may improve IVF outcomes.
Anonymous donor: A sperm or egg donor whose identity is not disclosed to the recipient(s). Regulations around donor anonymity vary by country.
Antagonist protocol: An IVF stimulation protocol using GnRH antagonist medications (e.g., Cetrotide or Ganirelix) to prevent premature ovulation. It is the most commonly used protocol and has a shorter treatment window.
ART - Assisted Reproductive Technology: A broad term covering all fertility treatments in which eggs or embryos are handled outside the body. Includes IVF, ICSI, egg freezing, and embryo donation.
Assisted hatching: A procedure where a part of the outer covering of the embryo, called the zona pellucida, is partially opened. Sometimes used to help the embryo attach better and increase the chances of pregnancy.
Baseline ultrasound: An ultrasound performed at the start of a treatment cycle (usually on cycle day 2–3) to check for cysts and confirm the ovaries are at rest before beginning stimulation medications.
Batch IVF / Egg banking: Accumulating eggs from multiple retrieval cycles before fertilising them all at once. This strategy is sometimes used for patients with diminished ovarian reserve to increase the number of eggs available.
CD138 immunostaining: A laboratory test performed on an endometrial biopsy to detect plasma cells, which indicate chronic endometritis (inflammation of the uterine lining). Treatment with antibiotics may improve implantation.
Coasting: A strategy used during IVF stimulation when estrogen levels become dangerously high. Stimulation medications are temporarily stopped while monitoring continues, allowing levels to decrease and reducing OHSS risk.
Controlled ovarian stimulation (aka "stims"): Treatment with certain fertility medications to cause more than one egg to develop. Previously called "superovulation" or "controlled ovarian hyperstimulation".
Controlled Ovarian Stimulation (COS) with Timed Intrauterine Insemination (IUI): A fertility treatment where medication is used to increase the number of eggs released by the ovaries. It's combined with placing sperm directly into the uterus around the time of ovulation.
Day 3 vs Day 5 transfer: Embryos can be transferred on day 3 (cleavage stage) or day 5 (blastocyst stage) after egg retrieval. Day 5 transfers often have higher implantation rates because the embryo has been further assessed for development.
Donor embryo: An embryo donated by another person or couple for use in fertility treatment. The recipient has no genetic connection to the embryo.
Donor insemination: When sperm from a donor is put into a woman’s vagina, cervix or womb to help start a pregnancy.
Dual trigger: Using both an hCG injection and a GnRH agonist (Lupron) as a trigger to mature eggs before retrieval. May improve egg maturity rates and reduce the risk of OHSS.
Egg freezing (oocyte cryopreservation): The process of stimulating the ovaries, retrieving eggs, and freezing them for future use. Commonly used for fertility preservation.
Egg retrieval: A process where an individual donates their eggs to help another person or couple get pregnant. The donated eggs are fertilized by sperm outside of the body to create an embryo. The embryos are then transferred to the recipient's uterus with the aim of achieving pregnancy.
Embryo transfer: A procedure whereby a medical team member places an embryo into the uterus via a catheter
EMMA test: A molecular test that analyses the endometrial microbiome to determine whether the uterine lining has the optimal bacterial balance (primarily Lactobacillus) for embryo implantation.
Endometrial scratch: A procedure in which the uterine lining is lightly scratched before an embryo transfer cycle. Some studies suggest it may improve implantation rates by triggering a healing response, though evidence is mixed.
ERA - Endometrial Receptivity Analysis: A biopsy-based test that evaluates whether the uterine lining is receptive to embryo implantation at the expected time. Results can help personalise the timing of embryo transfer.
Fertility preservation: Treatments or procedures to protect the ability to have children in the future. Options include egg freezing, sperm freezing, embryo freezing, and ovarian tissue freezing.
FET - Frozen Embryo Transfer: A procedure in which a previously frozen (cryopreserved) embryo is thawed and transferred into the uterus. FET cycles can be medicated or natural.
Freeze-all cycle: An IVF cycle in which all embryos are frozen rather than transferred fresh. This may be done to reduce OHSS risk, allow PGT results, or optimise the uterine lining for a later FET.
Fresh transfer: An embryo transfer performed during the same IVF cycle in which the eggs were retrieved, without freezing the embryo first.
Gestational carrier / Surrogacy: An arrangement in which a woman (the gestational carrier) carries a pregnancy for another person or couple. The carrier has no genetic link to the baby in gestational surrogacy.
Intended parent: The person or people who will be the legal and/or social parent(s) of a child conceived through donor gametes or surrogacy.
Known donor: A sperm or egg donor who is personally known to the recipient(s), such as a friend or family member, as opposed to an anonymous donor from a bank.
Mini IVF / Minimal stimulation IVF: An IVF approach using lower doses of stimulation medications (or oral medications like Clomid) to produce fewer but potentially higher-quality eggs. It involves less medication, lower cost, and reduced risk of OHSS.
Natural cycle IVF: An IVF approach that works with the body's natural menstrual cycle without stimulation medications, retrieving the single egg that develops naturally. It avoids the risks and costs of stimulation.
Oncofertility: A field that bridges oncology and reproductive medicine, focused on preserving fertility in patients about to undergo cancer treatment that may damage their eggs, sperm, or reproductive organs.
Open donor: A sperm or egg donor who agrees to be contacted by any donor-conceived children once they reach adulthood (usually age 18). Also called an identity-release donor.
Ovarian reserve: A woman's remaining supply of eggs. Ovarian reserve is assessed through blood tests (AMH, FSH) and ultrasound (antral follicle count). It naturally declines with age.
Reciprocal IVF: An IVF option for same-sex female couples where one partner provides the eggs and the other carries the pregnancy, allowing both partners to have a biological connection to the child.
Rescue ICSI: Performing ICSI on eggs that failed to fertilise with conventional IVF, typically done the day after retrieval. Success rates are generally lower than primary ICSI.
Social egg freezing: Egg freezing done for non-medical reasons, typically to preserve fertility options while waiting for the right partner or life circumstances.
Sperm bank: A facility that collects, screens, freezes, and stores donated sperm for use in fertility treatments such as IUI or IVF.
Split cycle (ICSI + conventional): An IVF cycle in which half the eggs are fertilised using conventional IVF and the other half using ICSI. This can be useful for unexplained infertility or mild male factor.
DPT - Days Past Transfer: A way of counting the days after an embryo transfer, used to track when to test for pregnancy and interpret hCG levels.
IVF - In Vitro Fertilisation: A technique where eggs are collected from a woman and fertilised with a man’s sperm outside the body. Usually one or two embryos are then transferred to the womb. If one or more of them implants successfully, the woman becomes pregnant.
Monitoring appointments: Regular ultrasound and blood test appointments during a fertility treatment cycle to track follicle growth, hormone levels, and determine the optimal timing for trigger shot or egg retrieval.

Labs & Hormones (7) ▸

DNA fragmentation (sperm): A test measuring the amount of damaged DNA within sperm. High levels of DNA fragmentation may reduce fertilisation rates and embryo quality, and increase miscarriage risk.
Enzyme: A protein found in cells that speeds up chemical reactions in the body.
Estradiol: The predominant estrogen (hormone) is produced by the follicular cells of the ovary.
Morphology (sperm): The size and shape of sperm as evaluated under a microscope. Abnormal morphology can affect the sperm's ability to fertilise an egg.
Motility (sperm): The ability of sperm to move and swim effectively. Good motility is essential for sperm to reach and fertilise an egg.
SA - Sperm analysis: A laboratory test evaluating sperm count, motility (movement), morphology (shape), and volume. It is one of the first tests performed in a male fertility evaluation.
Sperm count: The number of sperm present in a semen sample. A normal count is generally considered to be 15 million or more per millilitre of semen.

Medication (22) ▸

Anti-inflammatory (drugs): Medicines to stop or reduce swelling and redness.
Antibiotics: Medicines to fight an infection caused by bacteria.
Anticoagulant (medication): Medicines to reduce clotting in the blood vessels.
Antispasmodic drugs: Drugs which relieve cramps or spasms of the stomach, intestines, bladder and womb (uterus).
Baby aspirin: Low-dose aspirin (81 mg) sometimes prescribed during fertility treatment to improve blood flow to the uterus and support implantation. Also used in patients with antiphospholipid syndrome.
BCP or BC or Birth control pill: Also called oral contraceptives, birth control pills have synthetic estrogens and progesterone. When used correctly, they stop ovulation and reduce the production of hormones, like androgens, from the ovaries.
Cetrotide / Ganirelix (GnRH antagonists): Injectable medications used during IVF to prevent premature ovulation by blocking the action of GnRH. They are a key part of the antagonist stimulation protocol.
Clomid (Clomiphene citrate): An oral fertility medication that stimulates ovulation by blocking estrogen receptors in the brain, causing the body to produce more FSH and LH. One of the most commonly prescribed fertility drugs.
Doxycycline (for embryo transfer): An antibiotic prescribed around the time of embryo transfer or egg retrieval to prevent infection. Both partners may be given a short course.
Endometrin, Prometrium: A vaginal progesterone insert used for luteal phase support after embryo transfer, providing progesterone directly to the uterine lining.
Estrace / Estradiol patches: Estrogen medications used in fertility treatment to thicken the uterine lining in preparation for embryo transfer, particularly in FET cycles.
Heparin: A type of anti-coagulant medication that is given by injection.
Intralipids or Intralipid infusion: An intravenous fat emulsion sometimes used in fertility treatment to modulate the immune system, particularly in patients with elevated natural killer cell activity. Evidence for its effectiveness is still emerging.
IVIG - Intravenous Immunoglobulin: A blood product given by IV infusion containing antibodies. Sometimes used in reproductive immunology to suppress an overactive immune response that may be affecting implantation or pregnancy.
Letrozole (Femara): An aromatase inhibitor commonly used off-label to induce ovulation. Often the first-line treatment for ovulation induction in PCOS patients.
Lovenox (Enoxaparin): A blood-thinning (anticoagulant) injection sometimes prescribed for fertility patients with clotting disorders or a history of recurrent miscarriage to improve blood flow to the uterus and placenta.
Lupron (GnRH agonist): A medication that initially stimulates and then suppresses the pituitary gland's production of FSH and LH. Used in IVF to prevent premature ovulation and sometimes as a trigger shot.
Menopur / Gonal-F (gonadotropins): Injectable fertility medications containing FSH (Gonal-F) or FSH plus LH (Menopur). Used to stimulate the ovaries to produce multiple eggs during IVF or ovulation induction.
PIO - Progesterone in oil: An intramuscular injection of progesterone used to support the uterine lining after embryo transfer. One of the most common forms of luteal phase support in IVF.
Steroids or Corticosteroids (incl. Prednisone, Medrol, dexamethasone etc.): A group of hormones which may be used to suppress the body’s immune response or to reduce inflammation. Corticosteroid medications can sometimes be used during IVF to suppress the immune system and reduce inflammation, potentially improving implantation in certain patients. Also used during pregnancy in women who are thought may have their baby prematurely. They reduce the chance of the baby having problems from being born prematurely. See also steroids.
Trigger shot: An injection of hCG or a GnRH agonist (such as Lupron) given to trigger final egg maturation before egg retrieval. Timing is critical — retrieval typically occurs 34–36 hours after the trigger.
Valium (for transfer): A mild sedative (diazepam) sometimes given before embryo transfer to relax the uterus and reduce cramping during the procedure.

Procedures / Protocols (26) ▸

Abortion: Ending a pregnancy using either medicines (medical abortion) or an operation (surgical abortion, a type of abortion using suction instruments or D&E to end a pregnancy)
Biopsy: When a small piece of tissue is taken for examination under a microscope. The term also refers to the tissue that has been removed.
Cerclage: Placement of a nonabsorbable suture around an incompetent (weak) cervical opening in attempt to keep it closed and thus prevent miscarriage. Also known as a cervical stitch.
D&C - Dilation and curettage: A surgery where the cervix is opened, and the lining of the uterus is scraped. The tissue collected is usually examined under a microscope for any abnormalities or signs of pregnancy.
D&E - Dilatation and evacuation: Surgery using instruments to end the pregnancy.
Endometrial biopsy: The removal of a small piece of tissue from the endometrium (uterus lining) for microscopic examination. The results may indicate whether or not the endometrium is at the appropriate stage for successfully implanting a fertilized egg (embryo) and/or if it is inflamed or diseased.
Flare protocol (short protocol): An IVF stimulation protocol in which a GnRH agonist is started at the same time as stimulation medications, using the initial hormone flare to boost follicle recruitment. Often used for poor responders.
HSG - Hysterosalpingogram: An X-ray of the fallopian tubes or the womb, using fluid injected through the cervix.
Hysterectomy: An operation to remove the cervix and womb, carried out through a cut on the abdomen (abdominal hysterectomy) or the vagina (vaginal hysterectomy). The ovaries can be removed at the same time, if necessary.
Hysteroscopy: A quick procedure that uses a thin, lighted camera (hysteroscope) inserted through the cervix to examine or treat the inside of the uterus. It is used to diagnose causes of abnormal bleeding, remove polyps/fibroids, examine the structure of the uterus etc.
IUI - Intrauterine insemination: A form of assisted conception which places sperm into a woman’s womb through the cervix.
Laparoscopy: Surgical procedure whereby a doctor inserts a long, thin, lighted telescope-like instrument (a laparoscope) into the abdomen, through keyhole-sized openings in the navel and pelvis area (involving up to four small cuts). Can be diagnostic/explorative (e.g., to detect abnormalities of the internal pelvic organs, such as endometriosis), or can be operative (to treat or correct tissues, such as endometriosis tissues excision, cysts or fibroids removal etc.)
Long agonist protocol (long Lupron): An IVF stimulation protocol in which a GnRH agonist (Lupron) is started before stimulation to suppress the pituitary gland, giving the doctor full control over the cycle. It requires more time but can produce a more synchronised follicle response.
Micro-TESE: A microsurgical version of TESE using a high-powered microscope to identify areas of the testicle most likely to contain sperm. It has a higher sperm retrieval rate than conventional TESE.
Microdose Lupron flare: A variation of the flare protocol using very small doses of Lupron to create a mild hormonal flare that stimulates the ovaries. Often used for patients with diminished ovarian reserve.
Mock transfer: A practice embryo transfer performed before the actual transfer to map the path through the cervix and into the uterus, ensuring the real transfer goes smoothly.
Pelvic examination (internal): A check to feel the size and position of the womb and other reproductive organs to rule out any abnormality or problem.
ReceptivaDx / BCL6 testing: A test performed on endometrial tissue that measures BCL6 protein levels to screen for endometriosis affecting the uterine lining. Elevated BCL6 may indicate hidden endometriosis impacting implantation.
Saline sonohysterogram (SIS/SHG): An ultrasound procedure in which sterile saline is infused into the uterus to provide a clearer view of the uterine cavity. Used to detect polyps, fibroids, and other abnormalities.
TESA - Testicular Sperm Aspiration: A procedure in which sperm is extracted directly from the testicle using a needle, often used when there is no sperm in the ejaculate (azoospermia). The retrieved sperm can be used for ICSI.
TESE - Testicular Sperm Extraction: A surgical procedure to remove small pieces of testicular tissue to find sperm for use in ICSI. Used in cases of non-obstructive azoospermia.
Threatened miscarriage: Bleeding before 24 weeks of pregnancy which occurs without harm to the baby.
Trio test (ERA+EMMA+ALICE): A combined endometrial test package from Igenomix that includes ERA (receptivity), EMMA (microbiome), and ALICE (infection) testing, all from a single biopsy.
Tubal occlusion: An operation which blocks, seals or cuts the fallopian tubes. Also known as sterilisation. It is a permenant method of contraception for women.