Speaking the language of infertility - key terms explained

Speaking the language of infertility - key terms explained

Nav Arrow Left TTC? Make this Valentine’s Day extra special Reading Speaking the language of infertility - key terms explained 12 minutes Next Facts about Endometriosis Nav Arrow Right

Published March 2022

Fertility Glossary A-Z Key Terms Explained 

Here is a useful glossary of medical and fertility terms that will help you make sense of the vocabulary you hear when researching or undergoing fertility treatments. 


Adoption: The legal process in which a couple adopt a child and become its legal parents.

Andrology: The branch of medicine concerned with men’s health, particularly male infertility and sexual dysfunction

Anovulatory: The absence of ovulation, failure to release an egg.

Antral Follicles: Small egg sacs which develop in the ovary at the start of the menstrual cycle. 

Antral follicle count: the total number of egg sacs in both ovaries. A count of 14 and above indicates good ovarian function. 

Artificial Insemination: Involves injecting filtered sperm into the uterus in order to improve the chances of pregnancy.

Assisted Hatching: The thinning of the shell or creation of a small hole in the zona of an embryo.

Assisted Reproductive Technology (ART):  Procedures that help improve the chances of conception. Types of ART include in vitro fertilisation (IVF) and  intracytoplasmic sperm injection (ICSI).

Asthenozoospermia: Sperm with poor motility

Antisperm Antibodies: Sticky proteins on sperm causing immobilisation.

Azoospermia: Complete absence of sperm in the ejaculate.


Basal body temperature (BBT): The lowest temperature attained by the body during rest. During ovulation, the BBT rises by 1/4 - 1/2°C.

Blastocyst: The early stage of an embryo that is 5 days old and is a hollow ball of cells whose wall is comprised of a single layer of cells; the blastocyst is the liquid-filled sphere that implants in the wall of the uterus during implantation

Blastocyst Transfer: An embryo that has developed to five days and is transferred into the uterus.


Cervix: The opening to the uterus from the vagina.

Cervical Mucous: A fluid that enhances the transport of the sperm into the endometrial cavity.

Clomid/Clomifene Citrate: A fertility drug used to stimulate the release of hormones to bring on ovulation.

Corpus Luteum: A ruptured follicle. The corpus luteum releases Oestrogen and progesterone. If pregnancy does not occur, the Corpus Luteum stops producing Progesterone and the female will have a menstrual bleed.

Cryopreservation: The process of freezing commonly used for eggs, sperm or embryos. Cryopreservation of oocytes is a relatively recent development and is called vitrification.


Dysmenorrhea: Pain with menstrual bleeding.


Ectopic Pregnancy: A pregnancy in which a fertilised egg begins to develop outside the uterus normally used in reference to a pregnancy that develops in the fallopian tube.

Egg Collection: A procedure performed to collect the eggs produced from an IVF/ICSI cycle. This is performed under sedation.

Egg Donation: A woman donates following ovarian stimulation to another woman (recipient).

Electro-ejaculation: The use of electrical stimulation to aid production of a semen sample in impotent or paralysed men.

Embryo: A fertilised egg is called an embryo. 

Embryo transfer: A procedure following IVF/ICSI in which the embryo/s are replaced back into the uterus.

Endometriosis: A condition in which the lining of the uterus, called the endometrium, grows outside of the uterine cavity.  Often, this tissue is found in the pelvic cavity attached to the ovary or fallopian tubes.  

Endometrium: The lining of the uterus that grows throughout the menstrual cycle and is shed in the monthly menstrual cycle if an embryo does not implant.

Epididymis: Coiled tubing outside the testicles which store sperm.

Estradiol: A hormone secreted by the ovaries.

Estrogen: A female hormone secreted chiefly by the ovaries that stimulates the development of female secondary sex characteristics and promotes the growth and maintenance of the female reproductive system.


Fallopian Tubes: Tubes are connected to the uterus and positioned near the ovaries.  It is here that fertilisation of the egg and sperm occurs.

Fertilisation: The process that involves sperm penetration into the egg.

Fibroids: A benign tumour that occurs in the uterine wall. 

Foetus: The developing human after embryo stage from the ninth week of pregnancy to birth.

Follicle Stimulating Hormone (FSH): A hormone produced by the pituitary gland that stimulates the growth of the egg-containing follicle in the ovary.  In males it contributes to the production of sperm.

Follicle: A fluid filled sac in the ovary in which an egg grows and develops. Although the egg is microscopic, follicles can be visualised by ultrasound.

Follicular Tracking: Scanning a woman during a natural or medicated cycle to track the growth of the follicle/s.


Gametes: Male sperm and female eggs.

Gonadotropins: Gonadotropin Releasing Hormone (GnRH): Produced by the Hypothalamus, it enables the production of LH and FSH.

Gonadotropins: the hormones produced by the pituitary gland that control reproductive function. They are part of the reproductive cycle, i.e. FSH and LH.


Human Chorionic Gonadotropin (HCG): A hormone that is produced by the body in the early stages of pregnancy.  It enables the corpus luteum to continue producing Progesterone.  In assisted conception HCG is used 36 hours prior to egg retrieval to mature the eggs ready for the egg collection procedure.

Human Chorionic Gonadotropin (HCG): A drug that helps to mature eggs and is often used as a ‘trigger’.

Hydrosalpinx: Fluid in the fallopian tube.

Hypothalamus: A specialised gland in the brain that orchestrates the body’s hormonal changes.

Hypospadias: Congenital abnormality, affecting male offspring, in which the opening of the urethra is misplaced or malformed.

Hystero Contrast Sonography (Hycosy): Procedure which checks the patency of the fallopian tubes using ultrasound waves.

Hysterosalpingogram (HSG): Procedure which checks the patency of the fallopian tubes under X-ray conditions.

Hysteroscopy: A procedure in which the uterine cavity is visualised by a surgeon.  Can help in the diagnosis of fibroids or polyps.


Implantation: For a pregnancy to continue developing the embryo needs to embed into the lining of the womb, the endometrium.

In Vitro Fertilisation (IVF): A procedure that involves removing eggs from a woman’s ovaries and fertilising them in the laboratory. The resulting embryo/s are then replaced back into the woman’s womb.

Infertility: The inability to conceive after a year of unprotected intercourse (six months if the woman is over age 35) or the inability to carry a pregnancy to term.

Intra-Cytoplasmic Sperm Injection (ICSI): A procedure in which a single sperm is injected into a mature egg.  Normally offered to couples where the male sperm count is low or there is poor motility.  It can also be offered to couples who have experienced failed fertilisation following IVF.

Intrauterine Insemination (IUI): A procedure in which sperm is washed and prepared and then passed directly into the uterus via a fine catheter to enhance the chances of fertilisation.


Klinefelter’s Syndrome: A genetic condition in which men have an extra X chromosome.


Laparoscopy: A camera procedure in which the surgeon passes a small, lighted instrument by making a small incision under the belly button to explore the internal structure of the pelvis, in particular the ovaries, fallopian tube and the uterus.

Luteinising Hormone: like follicle stimulating hormone, is a gonadotrophic hormone produced and released by cells in the anterior pituitary gland. LH is an important hormone both men and women produce. For women, it helps release the egg from the ovary, and in men, it it is necessary for the process of sperm production and testosterone secretion. LH plays a role in puberty, menstruation and fertility.


Menstrual Cycle: Normally a 28 day cycle in which ovulation occurs around day 14 and if fertilisation does not occur, results in a bleed around day 28. The normal length is between 25 and 35 days.

Menorrhagia: Heavy menstrual bleeding.

Miscarriage: Spontaneous loss of an embryo or fetus.

Microsurgical Tubal Reanastomosis: A procedure used to reverse tubal sterilisation.

Morphology: The term used to describe the shape of sperm.

Motile Forms: Sperm with a heightened ability to swim.

Myomas (fibroids): Benign (non cancerous), smooth muscle tumors found in the female genital tract.


Oestrogen: A hormone that aids the thickening of the endometrium lining.  It is also produced in small quantities in the male.

Oligozoospermia: Low numbers of sperm in the ejaculate.

Oligo-asthenoteratozoospermia (OATS): Low numbers, reduced motility and abnormality of the sperm shape in the ejaculated sample.

Oocyte: The egg cell produced in the ovary, also called ovum, egg or gamete.

Open Approach (Abdominal Myomectomy): A surgical procedure in which only fibroids, are removed.  This preserves childbearing potential.  Myomectomy can be performed in different ways depending on the location of fibroids within the uterus.  The most common approach is abdominal myomectomy, which allows the surgeon to directly visualise the uterus and fibroids through an abdominal incision.

Ovarian Cysts: Sacs filled with fluid or semisolid material that develops on or within the ovary.  Most cysts are benign and disappear spontaneously without treatment.

Ovarian Hyperstimulation Syndrome (OHSS):  A condition due to excessive response of the ovaries to stimulation drugs, in which the ovaries enlarge and there may be nausea, abdominal swelling and shortness of breath. This develops after the trigger injection and you should always report it to the clinic or an emergency doctor.

Ovary: The female reproductive organ that produces eggs and estrogen on a monthly basis under hormonal influence from pituitary gland.

Ovarian Drilling: Surgical procedure offered to women with PCOS.  Small holes are drilled into the ovary to reduce the number of cysts present in an attempt to regulate the menstrual cycle and aid conception.

Ovulation: The release of the egg (ovum) from the ovarian follicle.

Ovulation chart: Many women trying to conceive will make up this chart which records their body temperature, mucus consistency and menstrual dates.

Ovulation Induction: Medical treatment performed to initiate ovulation.


Pelvic Adhesions: Abnormal bands of scar tissue that form in the pelvis and cause organs to stick or bind to one another.

PESA: Percutaneous Epididymal Sperm Aspiration.  A procedure involving sperm being retrieved directly from the epididymis using a needle.

Preimplantation genetic testing (PGT): The process of taking cells from an embryo to check the number of chromosomes or to test for a specific genetic abnormality.

PID: Pelvic Inflammatory Disease.

Polycystic Ovarian Syndrome: An endocrine disorder affecting the function of the ovaries.

PMT: Premenstrual Tension.  These are symptoms arising from hormonal changes, normally occurring a week before menstrual bleed. They can include irritability, tearfulness and mood swings.

Premature Ovarian Failure: Indicated by an elevated FSH.  The ovaries are no longer producing follicles, this can be due to congenital, genetic, or damage caused by toxic drugs, such as chemotherapy.

Progesterone: A female hormone secreted by the corpus luteum in the ovaries during the second half of a woman’s cycle.  It thickens the lining of the uterus to prepare for the implantation of a fertilised egg.


Retrograde Ejaculation: A condition in which semen enters the bladder during ejaculation instead of leaving the penis.


Semen Analysis: A standard test of a man's semen to check the number and shape of their sperm and it's motility.

Seminiferous Tubules: Sperm is developed and grows in the tubules.

Sperm: The gamete that contains the genetic material of the male.

Sperm Count: One of the parameter’s that is checked in a semen sample i.e. the number of sperm present in the ejaculate.

Sperm Donation: Donation of sperm, from another person, to help couples conceive.

Spermatogenesis: The production of sperm.

Sperm Motility: A parameter that it checked in the semen sample.  It is the ability of the sperm to swim to the egg that enables fertilisation to occur.

STD: Sexually transmitted disease, such as Chlamydia.

Surrogacy: A woman carries a pregnancy for a couple.


Teratazoospermia: High numbers of abnormal sperm in ejaculate.

TeSE: Testicular Sperm Extraction, involving sperm being retrieved from a biopsy of testicular tissue.

Testes: The body part where sperm is manufactured.

Testosterone: This hormone aids the production of sperm.  It is also found in smaller quantities in women.


Unexplained infertility: This is when a couple cannot conceive but no cause has been found despite the routine testing of both the man and woman.


Vagina: The birth canal leading to the uterus

Vaginal Ultrasound: Internal scan which enables clear images of the reproductive organs in a female.  This will be used to assess follicular development during treatment.

Varicocele: an enlargement of the veins within the loose bag of skin that holds the testicles (scrotum)

Vas deferens: Tubes which carry sperm from the epididymis to the urethra.

Vasectomy: A surgical procedure which cuts the passages that transport the sperm.


Zona: Shell surrounding the egg/embryo.

Zygote: An early stage in the development of a fertilized egg.

Continue reading

Facts about Endometriosis Nav Arrow Right

Facts about Endometriosis

TTC? Make this Valentine’s Day extra special Nav Arrow Right

TTC? Make this Valentine’s Day extra special