The International Council on Infertility Information Dissemination, Inc

Candidiasis (Yeast) -- An infection that may be uncomfortable and itchy and may impair fertility.

Cannula -- A hollow tube like that used for insemination.

Capacitation -- A process that sperm undergo as they travel through the woman's reproductive tract. Capacitation enables the sperm to penetrate the egg.

Catheter -- A hollow flexible tube used to aspirate or inject fluids.

CD56+ -- See Natural Killer Cells.

CDS -- cul de sac or region of the pelvis immediately behind the uterus.

Centrifuge -- A machine that separates materials with different densities by spinning them at high speed. Used in sperm washing.

Cerclage -- A surgical stitch (suture) used to try to keep cervix tightly closed. Used for women with Incompetent Cervix.

Cervical Stenosis -- A blockage of the cervical canal from a congenital defect or from complications of surgical procedures. See also cervix.

Cervical Smear -- A sample of the cervical mucus examined microscopically to assess the presence of estrogen (ferning) and white blood cells, indicating possible infection.

Cervical Mucus -- A viscous fluid plugging the opening of the cervix. Most of the time this thick mucus plug prevents sperm and bacteria from entering the womb. However, at midcycle, under the influence of estrogen, the mucus becomes thin, watery, and stringy to allow sperm to pass into the womb. See also cervix.

Cervicitis -- An inflamation of the cervix.

Cervix -- The opening between the uterus and the vagina. The cervical mucus plugs the cervical canal and normally prevents foreign materials from entering the reproductive tract. The cervix remains closed during pregnancy and dilates during labor and delivery to allow the baby to be born.

Cervix, Incompetent -- See Incompetent Cervix.

Chemical Pregnancy -- A pregnancy where hCG levels are detected, but the pregnancy is lost before a heartbeat is seen on an ultrasound. This is a very early miscarriage -- often before the woman misses a period.

Chlamydia -- A common bacterial sexually transmitted disease that can lead to Pelvic Inflammatory Disease.

Chocolate Cyst -- A cyst in the ovary that is filled with old blood; endometrioma. Occurring when endometriosis invades an ovary, it causes the ovary to swell. Frequently, patients with large endometriomas do not have any symptoms. If the cyst ruptures or the ovary containing the cyst twists, emergency surgery may be necessary. Usually treatment can be carried out through the laparoscope.

Chromotubation/Chromopertubation -- This test is usually done in combination with a diagnostic laparoscopy. It involves injecting colored liquid through the fallopian tubes and watching the ends of the tubes for the dye. Spillage of dye indicates patent (open) tubes.

Chromosome -- The structures in the cell that carry the genetic material (genes: DNA); the genetic messengers of inheritance. The human has forty-six chromosomes, twenty-three coming from the egg and twenty-three coming from the sperm.

Chromosome Analysis -- See Karyotyping.

Chorionic Villae Sampling (CVS) -- An alternative to amniocentesis that can be done earlier in the pregnancy. It is a biopsy of the placenta that is used to check for genetic abnormalities in the fetus.

Cilia -- Tiny hairlike projections lining the inside surface of the fallopian tubes. The waving action of these "hairs" sweeps the egg toward the uterus.

Cleavage -- The series of cell divisions, or one of the cell divisions, of the fertilized egg that results in the formation of the blastomeres and changes the single-celled zygote into a multicellular embryo.

Clomid -- A brand name of clomiphene citrate.

Clomiphene Citrate (Clomid, Serophene) -- A fertility drug that stimulates ovulation through the release of gonadotropins from the pituitary gland.

Clomiphene Citrate Challenge Test (CCCT, CCT) -- This test entails the oral (by mouth) administration of 100 milligrams of clomiphene citrate on menstrual cycle days 5-9. Blood levels of FSH are measured on cycle day 3 and again on cycle day 10. Elevated blood levels of FSH on cycle day 3 or cycle day 10 are associated with very low pregnancy. See "Clomid Use and Abuse".

Cloning: a form of asexual reproduction in which an exact genetic copy of an adult organism is reproduced. Asexual reproduction is the norm for certain simple life forms, like bacteria, yeasts, certain plants, and some snails and shrimp. More complex organisms reproduce sexually, which allows for reshuffling of the genetic material of two individuals to produce a third unique individual who is different from both parents, but who has some traits from each one. This process leads to diversity within a population. Each offspring is then different from its siblings and also from its parents.See the INCIID April 2004 Article: Cloning What's it All About? by Carlene Elsner, M.D.

Cloning (Reproductive) --- the cloned embryo is replaced into the uterus of a mature female of the species where it may implant and grow See the INCIID April 2004 Article: Cloning What's it All About? by Carlene Elsner, M.D.

Cloning (Theraputic) --- the cloned embryo is grown in the laboratory. The cells from the inner cell mass of the blastocyst when grown in tissue culture can sometimes produce a stem cell line. As with reproductive cloning, the success rate is low for the production of stem cell lines. However, if a stem cell line is produced, these cells are very primitive and totipotent which means that they have the potential to develop into any and all of the different cell types in the body. Also, the stem cell line is a perfect genetic match to the parent. See the INCIID April 2004 Article: Cloning What's it All About? by Carlene Elsner, M.D.

CMV -- See Cytomegalovirus.

COH -- Controlled Ovarian Hyperstimulation.

Colposcopy -- Use of a scope to examine the cervix for abnormal cells.

Conception -- The fertilization of an egg by sperm that leads to the creation of a new being.

Condom Therapy -- Therapy prescribed to reduce the number of sperm antibodies in the woman by using a condom during intercourse for six months or more and by the woman refraining from all skin contact with the husband's sperm. The woman's antibody level may fall to levels that will not adversely affect the sperm.

Cone Biopsy -- A surgical procedure used to remove precancerous cells from the cervix. The procedure may damage the cervix and thus disrupt normal mucus production or cause an incompetent cervix, which may open prematurely during pregnancy.

Congenital Adrenal Hyperplasia -- A congenital condition characterized by elevated androgens which suppress the pituitary gland and interfere with spermatogenesis or ovulation. Women may have ambiguous genitalia from the excess production of male hormone.

Congenital Defect -- A birth defect, acquired during pregnancy but not necessarily hereditary.

Conization -- Treatment for abnormal or precancerous cells on the cervix in which a cone-shaped section of the cervix is remove.

Continuing Infertile -- Someone who has gone through primary infertility, successfully given birth, and is trying for another child.

Controlled Ovarian Hyperstimulation (COH) -- Using fertility medications to stimulate the growth of multiple follicles for ovulation. Also called Superovulation.

Cord Blood -- See Video of Dr. Gad

Corpus Luteum -- The yellow-pigmented glandular structure that forms from the ovarian follicle following ovulation. The gland produces progesterone, which is responsible for preparing and supporting the uterine lining for implantation. Progesterone also causes the half-degree or more basal temperature elevation noted after ovulation. If the corpus luteum functions poorly, the uterine lining may not support a pregnancy. If the egg is fertilized, a corpus luteum of pregnancy forms to maintain the endometrial bed and support the implanted embryo. A deficiency in the amount of progesterone produced (or the length of time it is produced) by the corpus luteum can mean the endometrium is unable to sustain a pregnancy. This is called Luteal Phase Defect (LPD).

COS -- See Controlled Ovarian Hyperstimulation.

C-Peptide -- Is the connecting piece between insulin molecules. The C-peptide level can be used to gauge insulin production in the body.

C-Reactive Protein (CRP) -- A plasma protein that can be a marker for inflammatory activity.

Cryopreservation -- Freezing quickly and then storing, as in sperm, embryos, and, more recently, unfertilized eggs.

Cryptorchidism -- When one or both testicles fail to descend into the scrotum. See undescended testicles.

Cumulus Oophorus -- The protective layer of cells surrounding the egg.

Cumulus cell --- The nutrient cells that surround the egg (ova)

Cushing's Syndrome -- A condition characterized by an overproduction of adrenal gland secretions. The person will suffer from high blood pressure and water retention as well as a number of other symptoms. A concurrent elevation of adrenal androgens will suppress pituitary output of LH and FSH and result in low sperm production or ovulatory failure. A woman may also develop male secondary sex characteristics, including abnormal hair growth. Cushing's Disease is another condition in which these same symptoms occur, but as the result of a pituitary tumor.

Cycle Day -- The day of a woman's menstrual cycle. The first day (day 1) is when full flow starts before mid-afternoon.

Cyst -- A fluid-filled sac.

Cytomegalovirus (CMV) -- A group of viruses that cause enlargement of cells of various organs. Infection in a fetus can cause jaundice, high-tone deafness, eye problems, malformation, or fetal death.

Cytoplasmic Transfer -- An extension of in vitro fertilization which takes the genetic material from a mother's egg and combines it with the cytoplasma of a donor egg. Two methods of cytoplasm transfer were developed, one which transfers a small amount of cytoplasm by tiny needle from the donor to the recipient egg, the other transfers a larger amount of cytoplasm which is then fused to the recipient cytoplasm with electricity. See Cytoplasmic Transfer article.

Cytotoxin --- An antibody or toxin that attacks the cells of particular organs.