Glossary of Terms


Amniotic Sac

Comprised of the outer layer of membranes (chorion) that develop from a blastocyst and the inner layer of membranes (amnion). Fills with amniotic fluid and expands to allow the developing embryo to float inside.

Androgens

Male sex hormones responsible for the development of male sex organs and secondary sexual characteristics. In women excess luteinizing hormones may increase the production of androgens and high levels of androgens can cause symptoms such as acne and course hair in women with Polycystic Ovary Syndrome.

Antisperm Antibodies

Sperm antibodies (a blood protein produced to counteract a foreign substance) may destroy sperm by immobilizing and making them clump together.

Artificial Insemination

A method of inducing pregnancy by inserting sperm into the uterus (womb).

Assisted Hatching

A small opening is created in the outer layer of a fertilized egg (embryo), which is inserted into the uterus with the hope that it will successfully embed there.

Blastocyst

A fertilized egg (zygote) divides repeatedly as it travels down the fallopian tube to the uterus. The zygote is a solid ball of cells, but transforms into a hollow ball of cells called a blastocyst. The wall of the blastocyst becomes the outer layer of membranes that surround the embryo and together with an inner layer that develops (amnion) they form the amniotic sac.

Blastocyst Culture

For vitro fertilization procedures, embryos are developed (cultured) in the laboratory to the blastocyst stage, prior to insertion into the uterus to continue developing naturally.

Bromocriptine

A medication that prevents a woman's body from producing a hormone called prolactin.

Cervix

The lower end of the uterus, which extends into the vagina.

Clomiphene Citrate

Clomiphene citrate (Clomid, Serophene) is a synthetic drug commonly used to induce ovulation in women and is also used to treat Polycystic Ovarian Syndrome.

Corpus Luteum

A mass of tissue that forms in the ovary after ovulation and secretes the hormone progesterone in the second half of the normal menstrual cycle.

Electrolytes

When dissolved, salts in the body exist as charged particles called ions, which are collectively known as electrolytes. A disturbance in the level of sodium in the body affects blood volume, blood pressure, and can result in edema (a swelling of the feet, ankles and lower legs), and in some cases, kidney failure.

Embryo

A human offspring in the early stages following conception up to the end of the eighth week when it becomes known as a fetus

Endocrine

Relates to the glands that secrete hormones internally, directly into the lymph fluids or bloodstream.

Endometriosis

A medical condition in which patches of endometrial tissue, normally found only in the uterine lining (endometrium), are present and functioning in the ovaries or elsewhere in the body.

Epididymis

A coiled tube attached to the back and upper side of the testicle that stores sperm and is connected to the vas deferens. It provides the space and environment for sperm to mature and pass through to the vas deferens.

Epididymovasostomy

A microsurgical procedure used to bypass a block in the epididymis.

Estradiol

Is a major estrogenic hormone produced in the ovarian follicles, which can be synthesized for use in treating estrogen deficiency.

Estrogen (Oestrogen)

Any of several steroid hormones produced mainly in the ovaries that develops and maintains the female characteristics of the body.

Fallopian tubes

Either of two narrow tubes with a funnel-shaped end through which a woman's eggs pass from either of the ovaries to the womb. Fertilization of a woman's egg usually takes place in a fallopian tube.

Fibroids

Fibroids are benign (non-cancerous) growths comprised of muscle and fibrous tissue that grow on the uterus. They have been known to contribute to infertility by blocking the fallopian tubes or distorting the uterine cavity.

Follicle

The small cysts in the ovary where the egg develops.

Follicle stimulating hormone (FSH)

A pituitary hormone that stimulates the growth of egg follicles in the ovaries and in men, the making of sperm in the testes

Gonadotropins

Are hormones secreted by the pituitary gland and influence gonadal activity, including the onset of sexual maturity and regulation of reproductive activity.

Gonadotropin Releasing Hormone (GnRH)

A hormone released in pulses from the hypothalamus to modulate the release of follicle-stimulating hormone and luteinizing hormone from the pituitary in order to cause egg development and eventual ovulation.

GnRH Agonists

GnRH Agonists initially cause a release of FSH and LH from the pituitary gland. With continued use a GnRH agonist blocks or suppresses the action of GnRH (down regulate) to prevent a premature surge of LH that can result in premature ovulation.

GnRH Antagonists

GnRH Antagonists prevent the release of LH and FSH from the pituitary and prevent the LH surge.

Gonad

An organ that produces reproductive cells (gametes) in a testis or an ovary.

Hormones

A regulatory substance produced in the body's endocrine glands or certain other cells that are transported in tissue fluids such as blood, to stimulate cells or tissues into action

Human Chorionic Gonadotropins (hCG)

A hormone secreted by the placenta during pregnancy. HCG may also be administered for some infertility problems.

Hysteroscopy

A medical procedure whereby a thin, fibre-optic tube is inserted through the cervix into the uterine cavity for viewing. The instrument may contain a biopsy device for sampling tissue or an electrocautery (heat-sealing) device for removing abnormalities.

In Vitro Fertilization (IVF)

Fertilization of a woman's ovum (egg) with her partner's sperm, that takes place outside the body - i.e. in a dish in the laboratory, when normal conception is not achievable.

Intracytoplasmic sperm injection (ICSI)

The process of injecting a single sperm into a woman's egg. Resulting embryos are then placed in the uterus.

Intrauterine insemination (IUI)

Insemination performed by inserting washed sperm directly into the uterus.

Laparoscope

A tubular instrument, inserted through a small insertion in the abdominal wall to provide a view of the internal organs

Laparoscopy

A surgical procedure requiring a general anaesthesia that allows for examination of the internal organs of the abdomen using a laparoscope. Used to check for endometriosis, pelvic scarring, or to help retrieve eggs for in vitro fertilization.

Luteal Phase

The second phase of the menstrual cycle, during which levels of luteinizing hormone and follicle-stimulating hormone decrease and progesterone and estradiol cause the uterine lining to thicken.

Luteal Phase Defect

When the body does not produce enough hormones after ovulation.

Lupron

A medication that lowers the amounts of the hormone estrogen.

Luteinizing hormones (LH)

A hormone produced by the pituitary gland that causes the ovary to produce one or more eggs, to secrete the hormone progesterone and to form the corpus luteum.

Metformin

A medication for treating Polycystic Ovarian Syndrome (PCOS) and insulin resistance. A combination of Metformin and clomiphene citrate improve ovulation in the PCOS patient.

Menstrual Cycle

The shedding of the lining of the uterus (endometrium), accompanied by bleeding. Occurs in monthly cycles ranging from 21 to 40 days, unless a woman is pregnant.

Microsurgical Epididymal Sperm Aspiration (MESA)

A method of retrieving sperm cells from the epididymis or from a biopsy of testicular tissue.

Oocyte Retrieval

A needle is inserted through the wall of the vagina into the ovary and the egg (oocyte) is removed for use in IVF. Ultrasound is used to view the ovary. Egg retrieval takes place 34 to 36 hours after an injection of human chorionic gonadotropin (hCG).

Ovulation

One egg (ovum) is released from one of the ovaries about 14 days before the next menstrual period. The release of the egg is called ovulation.

Ovulation Induction (OI)

A medication therapy, which stimulates the growth and the release of eggs from the ovaries.

Ovarian Hyperstimulation Syndrome (OHSS)

Ovarian Hyperstimulation Syndrome is when a woman's ovaries become excessively enlarged as a result of hormone therapy that stimulates the development of follicles and prompts ovulation.

Ovulation

The ripening and discharge of an egg or eggs from the ovary for possible fertilization.

Preimplantation Genetic Diagnosis (PGD)

PGD technology allows for the manipulation of the blastocyst and the removal of a cell to perform genetic diagnosis.

Polycystic Ovarian Syndrome (PCOS)

A disorder in which the ovaries are enlarged and contain many fluid-filled sacs (cysts). The pituitary gland secretes excess amounts of lutenizing hormones, increasing the production of androgens (male hormones), some of which may be converted to chronically high levels of estrogens. Symptoms may include obesity, an increase in acne, coarse hair, or body hair growing on the face or chest, or profuse vaginal bleeding.

Pituitary gland

A pea-sized gland that sits at the base of the brain. The pituitary controls the function of most endocrine glands and is in turn controlled by the hypothalamus, a region of the brain that lies just above the pituitary.

Progesterone

An ovarian hormone controlled by the hypothalamus and pituitary that prepares the lining of the uterus for implantation of a fertilized egg.

Prolactin

A hormone regulated by the pituitary gland, which stimulates lactation and the secretion of progesterone.

Scrotum

The pouch of skin and muscle containing the testes.

Semen Analysis

The main screening test for male infertility including tests of sperm quantity, function and quality (ability to move, bind to and penetrate an egg)

Seminal Vesicles

A pair of glands that secrete the fluid component of semen into the ejaculatory duct in males

Testes

The roundish male reproductive glands that produce sperm and male sex hormones and hang in a small sac (scrotum) behind the penis

Uterus

The womb; the organ in which the fetus is developed and protected before birth.

Varicocele

A mass of veins in the scrotum, similar to varicose veins, that raises the temperature of the testes and reduces the rate of sperm formation.

Vas deferens

A cord-like duct that transports sperm from the epididymis to the back of the prostate and enters the urethra to form the ejaculatory ducts.

Zygote

A fertilized egg (zygote) that divides repeatedly as it travels down the fallopian tube to the uterus.