Glossary Of Fertility Terms

  • Acrosome
    Enzymes contained in the head of the sperm that allow the sperm to penetrate through the zona pellucida of the egg and undertake fertilization of the egg.
  • Adhesions
    Scarring that can occur in the abdomen or inside the uterus that can affect how the fallopian tubes and ovaries function or impair implantation of the embryo inside the uterus.
  • Adrenal Gland
    A small gland above each kidney that secretes hormones that affect reproduction.
  • Amenorrhea
    The absence of menstrual periods.
  • Anovulation
    The absence of ovulation.
  • Antibodies
    Proteins made by the body’s immune system to fight and destroy foreign substances and prevent infection. Some antibodies may attack sperm, causing infertility.
  • Aspermia
    The absence of semen and sperm in an ejaculate. This differs from azoospermia which is the absence of sperm in semen.
  • Assisted Hatching
    The use of micromanipulation procedures to create an opening in the zona pellucida of the embryo. This is used in conjuction with IVF.
  • Azoospermia
    Absence of sperm in the semen.
  • Basal Body Temperature (BBT)
    A woman’s lowest normal body temperature. It is measured in the morning before getting out of bed with a special type of thermometer. Charting BBT can be used to predict ovulation.
  • Blastocyst A five to six day old embryo that has developed to 50-100 cells.
  • Capacitation
    The changes that a sperm goes through to be capable of penetrating the zona pellucida layers covering the egg.
  • Cervical Mucus
    Mucus produced by the cervix. The amount and consistency of this mucus changes during the menstrual cycle and can be used by the patient to determine time of ovulation.
  • Cervix
    The lowest part of the uterus, which opens into the vagina.
  • Corpus Luteum
    A structure on the ovary which forms from an ovulatory follicle and which, through endocrine secretions (including progesterone), functions to prepare the uterus for pregnancy.
  • Cryopreservation
    The freezing and storage of living cells.
  • Cytoplasm
    The fluid which fills living cells and which contains essential cellular components including the nucleus.
  • Cyst
    A fluid-filled structure that can be seen in the ovary. It can be of a large range of sizes and there can be more than one.
  • Culture Media
    A specially formulated solution used in the laboratory to promote growth and division of a fertilized egg until the embryo transfer takes place.
  • Donor Insemination
    Artificial insemination with a donor’s sperm.
  • Ejaculate
    The semen and sperm-containing fluid produced on ejaculation.
  • Electroejaculation
    A procedure using electrical stimulation to induce ejaculation in a man with damage to the nerves that control ejaculation. Commonly used in men with spinal cord injury in order to obtain sperm to use for artificial insemination.
  • Embryo
    The term used to describe developing offspring during the period between fertilization and organ formation.
  • Embryo Transfer
    The transfer of embryo(s) into the uterus.
  • Embryologist
    A specialist in embryo development.
  • Endometriosis
    The presence of endometrial tissue (the cycling tissue which lines the uterus) at sites outside the uterus. These sites usually include the fallopian tubes, ovaries and peritoneal cavity. The condition is associated with pelvic pain, pain during menstruation and infertility.
  • Endometrium
    The cycling lining of the uterus. This structure receives the implanting embryo.
  • Estrogen
    The primary female hormone, produced mainly by developing ovarian follicles.
  • Epididymis
    The organ that stores sperm as they develop and pass from the testicles to the vas deferens.
  • Fallopian Tubes
    The structures which lie between the ovaries and uterus. They normally receive the ovulated egg and provide the site for fertilization and early embryo development.
  • Fertilization
    The process that results when an egg and sperm combine to create a zygote (which later divides to become an embryo). With natural conception, fertilization occurs in the fallopian tubes. With in vitro fertilization, it occurs in a laboratory dish. With intracytoplasmic sperm injection (ICSI) it occurs after the injection of the sperm into the egg.
  • Fetus
    The developing baby from the second month of pregnancy until birth.
  • Follicle
    The structure which houses the egg and subsequently fosters its development and ultimate ovulation. At birth, there are in excess of 100,000 follicles per female ovary. This number decreases continuously throughout life.
  • Follicle-stimulating hormone (FSH)
    Gonadotropic hormone released from the pituitary gland and functioning to stimulate ovarian follicular growth and development. The same hormone plays an essential role in male sperm production.
  • Gametes
    Male and female sex cells (sperm and eggs, respectively).
  • Gestational Sac
    The fluid-filled sac in which the fetus develops. In early pregnancy ultrasound, this is seen first.
  • Gonads
    Male (testes) and female (ovaries) organs which produce sex cells.
  • Gonadotropin Releasing Hormone (GnRH)
    A hormone that signals the pituitary gland to release the gonadtropins LH and FSH.
  • Gonadotropins
    Follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Hormones produced by the pituitary gland and which stimulate egg and sperm development in the ovaries and testicles repectively. Purified forms of these hormones are obtained from urine or genetically engineered cells.
  • Hormone
    A natural protein produced in one body tissue and carried via the bloodstream to initiate a response in another tissue.
  • Human Menopausal Gonadotropins (HMG)
    Gonadotropin (FSH and LH) preparations obtained from urine of post-menopausal women and commonly used in the treatment of infertility.
  • Hypothalamus
    A major control center within the brain. Among many functions, it regulates the secretion of gonadotropins (FSH and LH) by the pituitary.
  • Hysterosalpingogram (HSG)
    An X-ray using dye to view the shape of the uterus and the fallopian tubes. If the dye passes freely from the uterus through the fallopian tubes, the fallopian tubes are considered open.
  • Infertility
    The inability of a couple to achieve pregnancy through frequent natural intercourse after 6-12 months of trying. It can also be applied to the inability of the woman to carry a pregnancy to term.
  • Implantation
    The attachment of the embryo to the endometrium of the maternal uterus. This process ultimately gives rise to the placenta (respiratory and excretory system of the developing fetus).
  • In Vitro Fertilization (IVF)
    The generation of embryos outside the body by mixing eggs and sperm in tubes or dishes containing defined culture media. In the treatment of human infertility, IVF defines a multi-step process including: ovarian stimulation, egg retrieval, insemination of eggs in culture tubes or dishes containing defined media and transfer of resulting embryos back to the uterus.
  • Intracytoplasmic Sperm Injection (ICSI)
    The technique of injecting one sperm into the cytoplasm of the egg. It is used during IVF most commonly for treatment of male factor infertility.
  • Laparoscopy
    Visualization of reproductive organs using a fiberoptic scope inserted through a small abdominal incision at surgery.
  • Luteinizing Hormone (LH)
    A pituitary gonadotropic hormone which plays an essential role improving the development of sex cells (both eggs and sperm). A surge of LH causes final egg maturation and ovulation.
  • Maturation Arrest
    A condition in which sperm production stops before mature sperm are developed.
  • Oligospermia
    Abnormally low numbers of sperm in the ejaculate of the male.
  • Oocyte
    The female sex cell ovulated at the end of each reproductive cycle.
  • Ovary
    The female gonad containing the eggs (one egg per ovarian follicle). This structure also provides the chief source of estrogens and progesterone.
  • Ovulation Induction
    Medical treatment to start (induce) ovulation.
  • Penis
    The male organ of sexual intercourse.
  • Pituitary Gland
    The “Master” gland which ultimately controls virtually every other endocrine gland in the body. Through gonadotropin (FSH and LH) secretion, the pituitary regulates sex cell development by testes and ovaries.
  • Progesterone
    A hormone which plays a central role in the establishment and maintenance of pregnancy. Initially, it is secreted by the corpus luteum (a structure from where the egg ovulated from) to prepare the uterus for pregnancy. Later, it is secreted by the placenta to maintain pregnancy.
  • Prostaglandins
    A group of hormone-like chemicals that have various effects on reproductive organs.
  • Scrotum
    The sac containing the testicles, epididymis, and vas deferens.
  • Semen
    The sperm and seminal fluids ejaculated during male orgasm.
  • Sperm
    The male reproductive cells that carry genetic information to the female’s egg.
  • Sperm Morphology
    Part of a semen analysis test that checks the number of sperm that appear to have been formed normally.
  • Spermatogenesis
    The process of sperm production (within the testis).
  • Sperm Motility
    The ability of sperm to move or “swim” towards the egg.
  • Sperm Wash
    A technique that separates the sperm from the seminal fluid. It allows the isolation of the “best” sperm to be used for intrauterine insemination.
  • Spermicide
    An agent that kills sperm.
  • Testes
    The male gonad, functioning to produce mature sperm as well as the hormone testosterone.
  • Testicular Failure
    A condition in which the testes do not produce sperm or testosterone. This condition may have existed at birth or develop later in life or be caused by trauma or damage to the testicles. It may lead to male infertility.
  • Testosterone
    The male hormone needed for the production of sperm.
  • Unexplained Infertility
    Infertility where all test results are found to be normal.
  • Urologist
    A physician who specializes in male factor infertility and the surgical treatment of disorders of the urinary tract and male reproductive tract.
  • Varicocele
    A common condition in which the veins that carry blood out of the scrotum become dilated. When blood pools in these veins, the temperature in the scrotum increases. This may be a cause of male infertility.
  • Vas Deferens
    The tube that carries sperm from the testicles (epididymis) to the penis.
  • Vasectomy
    Surgical sterilization of a man by cutting, burning or crushing their vas deferens.
  • Vasectomy Reversal
    Surgical repair of a previous vasectomy for a man who wants to regain his fertility.
  • Zona Pellucida
    A proteinaceous barrier surrounding eggs and embryos. This is penetrated by sperm prior too fertilization.
  • Zygote
    A fertilized egg which has not yet divided.