Fertility Terms (In Alphabetical Order)
Amniocentesis- A procedure where amniotic fluid is removed from the amniotic sac to test for diseases in the developing fetus. This test is performed between 14-18 weeks of pregnancy.
Amniotic fluid- The fluid within the amnion (membrane that holds the fetus) forming a sac where the baby (fetus) develops.
Andrologist- A physician or scientist who performs clinical or laboratory evaluations of male fertility.
Anovulation- Lack of ovulation or no ovulation. This can be a chronic problem in some women leading to infertility.
Assisted Hatching (AH)- When an embryologist under microscopic assistance makes a small hole in the outer zona pellucida (egg membrane) to help the embryo inside hatch out of the membrane prior to embryo transfer.
Assisted Reproductive Technologies (ARTs)- Any technologies or techniques that involve assisting women to get pregnant or carry children. These include: in vitro fertilization (IVF), Intracytoplasmic Sperm Injection (ICSI), Assisted Hatching (AH), etc.
Asthenozoospermia- Low sperm count in the seminal fluid. Sperm is present, but the numbers are lower than normal which can cause infertility.
Azoospermia- The absence of sperm in the seminal fluid. This is a cause of male infertility.
Basal Body Temperature (BBT)- A method used to determine ovulation by taking the temperature of a woman daily. When the temperature rises it indicates that ovulation is about to occur. It can be used to help time intercourse when trying to conceive.
Beta hCG- The hormone tested for in the blood to determine pregnancy.
Blastocyst/Blastocyst Transfer- The point at which an embryo reaches a certain stage of its development, usually around day five of embryonic life. This is when Reproductive Health Center transfers the embryo(s) and when embryos are cryopreserved (frozen). Blastocyst transfer is when the embryo is transferred back into the uterus.
Chemical Pregnancy (or biochemical pregnancy)- This is when a woman has a positive pregnancy test that does not develop past the initial blood hCG test being positive. Usually the woman will start her period days later than her scheduled menses.
Clomid- The fertility drug used to stimulate FSH. See Clomiphene Citrate
Cervical Mucus- The secretions surrounding the cervical canal, where the amount and texture fluctuates depending on when ovulation occurs and if a woman is pregnant. The mucus facilitates the movement of the sperm through the cervix during ovulation and blocks sperm and diseases during pregnancy.
Cleavage- The first cell division in a zygote as it becomes an embryo.
Clomiphene citrate (Clomid)- A fertility drug that causes the production of more than one follicle at a time.
Corpus luteum (yellow body)- This structure develops in the ruptured ovarian follicle. It secretes progesterone after the egg has been released to maintain the uterine lining.
Deoxyribonucleic acid (DNA)- The hereditary material in all living organisms.
Donor- A person who allows their gametes (sperm or eggs) to be used for the production of a/an embryo(s) and later a child. All parental rights are given to the recipient.
Donor Insemination- Donor sperm is used in the vagina, cervix or uterus to inseminate the patient.
Ectopic Pregnancy- A pregnancy that implants and begins to develop outside of the uterus. Common sites for ectopic pregnancies are the fallopian tubes or pelvic cavity.
Egg (Oocyte)- The female gamete.
Egg collection or egg retrieval- Eggs are aspirated from a woman’s ovary with a fine needle. The needle is passed through the back wall of the vagina and into the ovaries. The eggs are then gently aspirated out of the follicles and into a collection tube. This is the first step in the in vitro fertilization (IVF) process.
Egg donation- A woman gives up her eggs for use by another woman. This is typically done by young women who want to help infertile women become pregnant and have children.
Embryo- An egg that has been fertilized by sperm and may mature into a fetus.
Embryo Biopsy- The removal and culture of cells from an embryo, in vitro, for genetic screening or testing.
Embryo Culture- Embryos are developed outside of the womb (uterus) in culture dishes in the laboratory (in vitro). This follows the fertilization of the egg and can be for two to six days.
Embryo freezing (cryopreservation)- Embryos are frozen either through a slow freeze process or vitrification for later use.
Embryo Storage- Storing the frozen (cryopreserved) embryos for future use.
Embryo Transfer- The process of transferring an embryo into a woman’s uterus through the cervix and with a thin flexible catheter.
Endometriosis– A condition where cells of the endometrium that normally line the uterus are found outside of the uterus (like in the pelvic cavity, fallopian tubes or on the ovaries). This usually can cause pain, internal bleeding and infertility.
Endometrium- The lining of the womb (uterus) that changes or is sloughed off during a normal menstrual cycle causing a period. During pregnancy, it supports the growing embryo.
Epididymis- A highly convoluted tube about seven meters long that connects the testes to the vas deferens. The sperm are moved along the tube and are stored in the lower part until ejaculation. Blockage of the epididymis will result in male infertility.
Estrogen- The female sex hormone produced by the ovaries that fluctuate normally during the 28 days of the menstrual cycle. Estradiol is the test used to determine the estrogen level during a fertility cycle.
Fallopian tubes- The organ of transportation of the egg from the ovary to the uterus. This is usually where conception occurs.
Fertilization- The event where a sperm penetrates the egg (oocyte) and a zygote results.
Fibroid- A ball of fibrous muscular tissue that may grow in the muscular wall of the uterus. This is a non-cancerous growth, but can cause pain and excessive menstrual bleeding and result in impaired fertility.
Fetus- After eight weeks the embryo is now referred to as a fetus until birth occurs.
Follicle(s)- A small sac in the ovary in which the egg (oocyte) develops.
Follicle Stimulating Hormone (FSH)- The pituitary gland produces this hormone in order to stimulate the production of follicles in the ovary. A blood test for FSH is done in the first few days of the menstrual cycle to determine if the ovaries have a reserve of eggs. If the FSH is below ten the ovaries are said to have good ovarian reserve. If the FSH is above ten, then the prognosis for pregnancy can be diminished.
Fresh vs. frozen cycle- Fresh cycle is used to indicate that the embryos transferred were produced in the cycle of the transfer and have not been frozen. Additional embryos from the cycle are then frozen (cryopreserved). Embryos transferred after they are thawed are referred to as frozen embryos, the cycle in which they are transferred is considered a frozen cycle or frozen embryo transfer (FET).
Fundus- The upper part of the uterus.
Gamete- The cells of reproduction. For females this is the oocyte or egg and for males it is the sperm. These cells have half of the genetic material of the normal body cells.
Gene- A linear sequence of nucleotides along a segment of DNA that provides the coded instructions for synthesis of proteins responsible for certain traits and characteristics within a living organism.
Genome- The basic set of genes in the chromosomes in cells, organisms and species.
Gonadotrpin Releasing Hormone (GnRH)- Hormone released by the hypothalamus, which stimulates the pituitary to produce Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH).
Gonadotropins- Fertility drug(s) used to encourage the ovaries to make more than one follicle (egg).
Human Chorionic Gonadotrophin (hCG)- A protein hormone that is secreted by a pregnancy into the blood. A blood test for hCG levels will determine if a woman is pregnant. This hormone is also injected to trigger ovulation and is often referred to as “the trigger shot”.
Hyper stimulation- See OHSS, this is the short name for ovarian hyper stimulation syndrome.
Hysterectomy-The surgical removal of the uterus (and sometimes the ovaries).
Hysterosalpinogram (HSG)- This procedure is an X-ray dye test of the uterus and fallopian tubes. It is used to determine if the fallopian tubes are open and if the uterine cavity is regular and clear.
Implantation- Occurs when an embryo burrows into the uterine lining after fertilization.
Inner cell mass- A cluster of cells growing within and to one side of the blastocyst cavity in the embryo. This mass of cells will form the baby.
Insemination- See IUI.
Intra Uterine Insemination (IUI)– Either frozen sperm or fresh sperm is washed and transferred into the uterine cavity through the cervix with a small catheter. IUI is used to treat male infertility and to improve the chances of conception in the female. It can only be used if at least one fallopian tube of the female partner is open. Donor sperm can also be used and is sometimes called donor insemination.
In Vitro Fertilization (IVF)– Eggs are removed from the female partner and fertilized in the laboratory with the male partner’s sperm or donor sperm. The resulting embryos are cultured outside the body and transferred later to the uterus, bypassing the fallopian tubes.
In vitro- Any process or reactions taking place outside of the body
In vivo- Any process that takes place inside of the body.
Laparoscopy- A surgical procedure used to examine or operate on the pelvic cavity with the use of fiber optic telescopes and instruments. The pelvic cavity is entered with small incisions in the belly.
Luteinizing hormone- (LH) This hormone is responsible for the eggs and sperm developing correctly and is released by the pituitary gland. In the female body the surge in LH begins the ovulation process.
Menstrual period or menstruation- This is the time in which the female uterus sloughs off its lining when no pregnancy occurs.
Menstrual cycle- A typical female menstrual cycle is 28 days long. Day one is the first day of bleeding from your menstrual period. Ovulation occurs normally on the 12th to 14th day and is only 24 hours long. An egg is released from the ovary and travels down the fallopian tube to the uterus during the luteal phase where it may or may not be fertilized. If it is not fertilized, the menstrual period will start again about 12 to 14 days after ovulation.
Miscarriage- The loss of a pregnancy before the fetus reaches 24 weeks.
Morula- The embryo after four days of development, this stage is the precursor to the blastocyst.
Natural cycle- A cycle in which no fertility drugs are given to stimulate follicle production.
Oocyte/Ovum- The female egg.
Ovaries- The female reproductive organs where eggs are created.
Ovarian Hyper stimulation Syndrome (OHSS)- Is a condition caused by fertility medication where the ovaries over-respond to the treatment by making many (sometimes as many as 50) follicles. It can cause extreme pelvic bloating, nausea and difficulty breathing. If moderate to severe, it may require hospitalization.
Polycystic Ovarian Syndrome (PCOS)– One of the leading causes of female infertility, this is an ovulation disorder where multiple small cysts are formed in the ovary, but the ovary does not ovulate correctly. This disorder can be complicated by obesity, diabetes and excessive hair growth. It should be managed under the care of a reproductive endocrinologist.
Preimplanation Genetic Diagnosis (PGD)– A technique where cells from the developing embryo are biopsied (removed) and tested for genetic disorders before the embryo(s) are transferred back inside of the female uterus.
Progesterone- The hormone produced by the ovary and by the corpus luteum after ovulation, which encourages the growth of the uterine (womb) lining.
Pro-nucleus- A small round structure(s) seen within the egg after fertilization which contains the haploid sets of chromosomes (genetic material from the egg and sperm) surrounded by a membrane. A normal fertilized egg (zygote) should contain two pro-nuclei, one from the egg and one from the sperm.
Singleton gestation- A pregnancy with only one baby.
Sperm- The male gamete produced by the men. Sperm are what determine sex of the potential child.
Stillbirth- The birth of a child that is not alive after 24 weeks of gestation.
Stimulation drugs- These drugs are used to produced more eggs in the ovaries with each menstrual cycle.
Superovulation- Medical stimulation of the ovaries to produce more than one egg within a single menstrual cycle.
Teratozoospermia- Poor sperm (abnormal) shape, which can cause the sperm to be ineffective at fertilizing the egg.
Ultrasound- A machine that uses high frequency sound waves to provide images of the uterus, ovaries and other internal structures using a wand inserted into the vagina, or rolled over the abdomen.
Unstimulated cycle- Also known as a natural cycle, where no drugs are given to stimulate the ovaries to make follicles.
Uterus- The female womb.
Vitrification- A way to cryopreserve (or freeze) eggs or embryos. The word means “to make like glass,” this process freezes without the formation of crystals in the cells.
Zona drilling- The use of chemicals to dissolve the gelatinous coating of the egg leaving a hole through which the sperm can enter.
Zona pellucida- The transparent membrane or shell surrounding the oocyte (egg).
Zygote- The fertilized egg. The cell now has both male and female DNA and with cell division will become an embryo.