Fertility Glossary A – C
Abortion – The premature ending of a pregnancy before the twenty-fourth week, either spontaneously or because of operative intervention. The medical profession also use the term “abortion” as a description of miscarriage.
Adhesion – An abnormal sticking together of surfaces covered by membranes. These can be fine “cobweb” like or thick and dense, and can interfere with the movement of ovaries, tubes and bowel.
Agglutination – The sticking together (clumping) of sperm. This can often indicate the presence of sperm antibodies.
Amenorrhoea – The absence of menstruation (periods).
Amniocentesis – A procedure performed around the 18-20th week of pregnancy. A small quantity of amniotic fluid from around the developing foetus is extracted to either determine the sex of the foetus, to check for abnormalities such as Down’s syndrome and also to detect and inherited genetic diseases.
Amnion – The inner membrane lining the foetal sac.
Ampulla – A widening of the tube e.g. the end of the vas deferens in which some sperm is stored. Also the ovarian end of the fallopian tube where fertilisation takes place.
Androgen – A male sex hormone produced by the testes responsible for male characteristics e.g. hair growth, deep voice and sperm production.
Andrologist – A doctor who specialises in male infertility and sexual disorders i.e. sperm and hormone production. Currently also used to name a scientist who analyses semen, previously termed a Seminologist.
Andrology – The study of diseases specific to the male reproductive system.
Aneuploidy – The loss or gain of one or two chromosomes. In a healthy human, all cells have 46 chromosomes, but occasionally around fertilisation time mistakes sometimes occur which result in each cell having e.g. 44, 45, 47 or 48 chromosomes. An embryo with only 44 or fewer chromosomes never survives the whole pregnancy and is lost by spontaneous miscarriage. Most of the other abnormal numbers do also, but some do go to full term pregnancy. The best-known and most frequent examples of aneuploidy results in a Down’s syndrome baby.
Anovulation – No ovulation. Menstrual cycles in which an egg is not produced. A woman can still have periods yet not be ovulating.
Antibody – A specific protein produced by the body in response to a challenge from a foreign substance known as an antigen. Men and women may produce antibodies for example to sperm.
Antisperm Antibodies – production of antibodies to sperm – the current treatment is IVF/ICSI.
Array CGH – Known as Comparative Genomic Hybridisation (CGH), uses a laser to cut a hole at the edge of the egg to remove an extra copy of all the egg’s chromosomes from a structure known as the ‘polar body’. This can then be examined for chromosomal abnormalities without disturbing the main genetic material of the egg itself.
Artificial Insemination – The introduction of semen into the female genital tract by means other than sexual intercourse.
Asherman’s Syndrome – Scar tissue in the uterus causing the sides to “stick” together. This is sometimes caused by over vigorous “scraping” during a D & C following a miscarriage. Specialist surgery is needed to remove the scarring and encourage the build-up of endometrium.
Aspermia – Failure to discharge seminal fluid at orgasm.
Assisted Hatching – Technique involving the artificial creation of an opening in the outer covering of the zona pellucida of the embryo. Used to help the normal growing embryo to emerge from the covering in order to implant properly in the uterus. Can be done by use of lasers, chemicals or mechanically.
Asthenozoospermia – Poor motility (movement) of sperm in the semen.
Azoospermia – An absence of sperm in the ejaculate.
Balanced Translocation – In a balanced translocation, a person usually has all the genetic material necessary for normal growth. A piece of a chromosome becomes broken off and attached to another one. However, when that person’s cells divide to create egg or sperm cells for reproduction, the egg or sperm cells can end up with extra genetic material, or missing genetic material which could possibly lead to miscarriage depending on which chromosome and genes are affected.
Basal Body Temperature – The body temperature taken orally, vaginally or rectally, usually after a rest and before any activity. Known as BBT.
Bicornuate Uterus – An abnormality of the uterus that occurs before birth. A partial or complete vertical division of the body of the uterus. Bicornuate means “two-horned”.
Biopsy – The taking of a small piece of tissue from the body for laboratory examination.
Blastocyst Transfer – This is performed when the embryos are cultivated for 4-5 days to approximately 64-cell stage at embryo transfer.
Blighted Ovum – A fertilised ovum that fails to develop into an embryo and usually results in an early miscarriage.
Candida – Also known as “thrush”. A minor infection of the vagina or the glans of a male penis. It causes soreness, irritation and sometimes a discharge and is easily treated with cream, pessaries or medication. It is important to treat both partners to prevent the problem recurring.
Capacitation – A process that occurs in sperm, which gives them the ability to penetrate and fertilise an ovum, as they pass through the female genital tract. This can also be mimicked in a culture medium when assisted techniques of reproduction are taking place.
Cervical Mucus – A secretion from the lining of the cervical canal.
Cervical Smear – Also known as a PAP smear “Papanicolaou” test. A simple test offered to all women and involves a cell sample being taken from all around the neck of the womb. This is then tested for any infection and for pre-cancerous cells.
Cervix – The neck or opening of the womb, which protrudes into the vagina.
Chemical Pregnancy – This happens when a fertilized egg does not attach itself to the uterine wall. This is also known as a very early miscarriage.
Chicago Test – This is a list of blood tests that check the complete make up of your blood. They look for antibodies or anti-rejection elements of your blood that might cause your body to reject a developing embryo. They check if you have thick blood too that could stop your egg from implanting. A very complicated test requiring the collection of many “phials” of blood.
Chlamydia – A common sexually transmitted infection that if left untreated, can cause tubal damage in the female and affect sperm quality in the male. Tests and treatments are needed for both partners before assisted conception.
Chorionic Villus Sample (CVS) – A sample of the placenta taken for genetic testing. The range for tests is similar to amniocentesis, but CVS can be done earlier in pregnancy at around 9-11 weeks gestation.
Chromosomes – Structures within every body cell that carry the hereditary material DNA.
Cilia – Hair-like projections. Those lining the fallopian tubes assist with the movement of the egg and sperm.
Cleavage – The division of a fertilised cell. Usually after about 26 hours after fertilisation occurs.
Clinical Commissioning Groups (CCGs) – are NHS organisations set up by the Health and Social Care Act 2012 to organise the delivery of NHS services in England.
Clomiphene (Clomid) – An anti-oestrogen used to stimulate ovulation.
Coitus – Sexual relations, making love, intercourse.
Comparative Genome Hybridisation (CGH) – The new method, known as Comparative Genomic Hybridisation (CGH), uses a laser to cut a hole at the edge of the egg to remove an extra copy of all the egg’s chromosomes from a structure known as the ‘polar body’. This can then be examined for chromosomal abnormalities without disturbing the main genetic material of the egg itself.
Conception – The joining together of the egg and sperm through to implantation.
Condom – Contraception sheath. French letter. Sheath.
Congenital – A characteristic or defect present at birth.
Cornu – The “horns” of the uterus where the fallopian tubes meet the uterus.
Corpus Luteum – A small yellow structure developing within the ruptured ovarian follicle after the egg has been released.
Cryopreservation – Preserving substances at very low temperatures in liquid nitrogen at –196 degrees centigrade. E.g. frozen sperm, embryos, eggs, testicular tissue and ovarian tissue.
Cryptorchidism – Undescended testes, for which, surgery is usually recommended and performed as a child
Cytomegalovirus (CMV) – A virus, which can cause severe disease in unborn babies if their mother catches the infection during pregnancy. Infection is common and by childbearing age 60-80% of the population will have been exposed to the virus. Catching the virus during pregnancy is not common.