Capacitation
The process by which sperm become capable of fertilizing an egg.

Catheter
A flexible tube used for aspirating or injecting fluids.

Cauterize
To destroy tissue with heat, cold, or caustic substances usually to seal off blood vessels or ducts.

Cervicitis
Inflammation of the cervix.

Cervix
The lower portion of the uterus that opens into the vagina.

Chlamydia
A type of bacteria that is frequently transmitted sexually between partners of from an infected mother to her newborn child; the most common sexually transmitted bacterial disease.

Chorionic villus sampling (CVS)
Taking a biopsy of the placenta, usually at the end of the second month of pregnancy, to test the fetus for genetic abnormalities.

Chromosome
Threads of DNA in a cell’s nucleus that transmit hereditary information.

Cleaved embryo
A fertilized oocyte which has undergone cellular division.

Clinical pregnancy
An ultrasound-confirmed gestational sac within the uterus or with an increasing level of hCG (human chorionic gonadotropin).

Colposcopy
Examination of the cervix through a magnifying telescope to detect abnormal cells.

Conception
The fertilization of a woman’s egg by a man’s sperm to form a zygote.

Condom
A latex (rubber) device that fits over the penis to prevent pregnancy and sexually transmitted infections.

Congenital defect
A birth defect.

Conization
Surgical removal of a cone-shaped portion of the cervix, usually as a treatment for a precancerous condition.

Contraindication
A reason not to use a particular drug or treatment.

Controlled ovarian hyperstimulation (COH)
Pharmacologic stimulation of the ovaries, generally with gonadotropins and/or clomiphene citrate, with the objective of stimulating the development of multiple follicles and hence retrieval of multiple eggs.

Corpus luteum
A special gland that forms on the surface of the ovary at the site of ovulation and produces progesterone during the second half of the menstrual cycle. Its function is necessary to prepare the uterine lining for implantation by the fertilized egg.

Cryocautery
Cautery by freezing.

Cryopreservation
A technique that involves freezing and preserving embryos or sperm for transfer at a later date.

Cryptorchidism
Failure of one or both testicles to descend into the scrotum.

Cul-de-sac
Pouch located at the bottom of the abdominal cavity between the uterus and rectum.

Culdoscopy
Examination of the internal female pelvic organs through an incision in the vagina.

Cyst
A sac filled with fluid.