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Medical terms explained

This alphabetical list contains explanations of medical words you may come across on the RCOG website or when you see your doctor.

We try to use as little medical jargon as possible in our information for the public. This list was developed by the Patient Information Committee, with input from the RCOG Women’s Network.

We add more terms to this list whenever we publish new information for the public. We aim to continually expand and improve this information and welcome your feedback – please email us with your comments and suggestions.

The explanations in this list are based on information available on the RCOG website and on the following websites:

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


Abdomen The tummy area from the lower ribs to the pelvis.
Abdominal Of the abdomen.
Abortion Ending a pregnancy using either medicines (medical abortion) or an operation (surgical abortion).
Acute Sudden and severe.
Adenomyosis Endometriosis in the muscle wall of the uterus.
Adhesions Scars that connects two or more body structures together.
Amniocentesis A way of testing the fluid surrounding a baby in the womb by taking a small sample with a needle put into the womb through the abdomen. It can be carried out after the 15th week of pregnancy, and can detect some conditions, like Down syndrome.
Amniotic fluid The watery liquid surrounding and protecting the growing fetus in the uterus.
Anaemia A condition when the level of haemoglobin, the protein in blood which carries oxygen round the body, is lower than normal. It can be mild or severe and can cause tiredness, breathlessness, fainting, headaches. It can also cause your heart to beat faster.
Anaesthesia A medical way of relieving pain.
Anaesthetist A doctor trained to administer anaesthetics.
Anal sphincter The muscle around the anus that is squeezed to prevent passing wind or opening the bowels involuntarily.
Before birth.
Anthracyclines Antibiotic drugs used in cancer chemotherapy.
Antibiotics Medicines to fight an infection caused by bacteria.
Antibody Blood protein that helps fight attacks on the immune system, such as those caused by bacteria and viruses.
Anticoagulant medication Medicines to reduce clotting in the blood vessels.
Anti-D See RhD antigen.
Antigen A substance in the blood that helps trigger the immune system to develop antibodies. See blood group.
Anti-inflammatory drugs Medicines to stop or reduce swelling and redness.
Antiretroviral drugs/therapy Medicines used to block the action of retroviruses (such as the HIV/AIDS virus) and the progress of infection. See also HAART, HIV and retrovirus.
Antispasmodic drugs Drugs which relieve cramps or spasms of the stomach, intestines, bladder and womb (uterus).
Anus The opening of the rectum to the outside of the body.
Assisted birth
(instrumental birth/operative vaginal delivery)
When special instruments (forceps or ventouse) are used to help deliver the baby during the pushing part of labour.
Assisted conception/assisted reproductive techniques (ART) Treatments to help people conceive a baby. See also: intrauterine insemination, in vitro fertilisation, intracytoplasmic sperm injection, donor insemination.
Autoimmune response When the body produces antibodies which react against the body’s own tissues.

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Bacteria Tiny organisms that may cause certain infections.
Bacterial vaginosis (BV) A very common vaginal infection which results in discharge and soreness. It is caused by an imbalance in the types of bacteria in the vagina. It is not sexually transmitted and does not affect men.
Bicornuate uterus (womb) A heart-shaped uterus. Usually the uterus would be pear-shaped.
Biopsy The taking of a small sample of tissue for examination.
Birth asphyxia When a baby has experienced a reduced level of oxygen around the time of birth. Affected babies may not breathe normally and may have a low heart rate.
Bladder The organ in the pelvis which stores urine before it is passed out through the urethra.
Blood group The way blood is classified by proteins (known as antigens) on the surface of your red blood cells. Group A blood has A antigens, group B blood has B antigens, group AB blood has both A and B antigens and group O blood has no antigens.
Body mass index (BMI) A measurement to work out the range of healthy weights for a person. It is calculated by dividing your weight (in kilograms) by your height (in metres squared – that is, your height in metres multiplied by itself). The healthy range is between 19 and 25.
Brachial plexus injury Damage to the nerves in a baby’s neck.
Breech position When the baby is lying bottom first in the womb.

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CA125 A protein in the blood that is raised in ovarian cancer. It can also be raised in endometriosis, pregnancy and infection.
Caesarean delivery An operation to deliver the baby by cutting through the wall of the abdomen and the uterus. It may be done as a planned (elective) or an emergency procedure.
Cancer A disease of the cells.
Candida albicans See vaginal thrush.
Cardiotocography (CTG) A machine which traces the baby’s heart rate and the woman’s contractions before and during birth to assess the baby’s wellbeing.
Catheter A small tube that can be passed through a part of the body, for example through the urethra (to empty the bladder).
Cell The tiny building blocks which make up the organs and tissues of the body.
Cephalhaematoma A bruise on the newborn’s head caused by a suction cup being used to help deliver the baby.
Cervix The entrance or neck of the womb, at the top of the vagina.
Chickenpox A viral infection (also called herpes zoster, varicella or varicella zoster). If a pregnant woman catches chickenpox, it may cause problems for her baby.
Chignon A swelling on the baby’s head as a result of a ventouse birth. It settles within a day or so.
Chlamydia trachomatis A sexually transmitted infection which can damage the reproductive system of both men and women if it is not treated promptly. Chlamydia is treated with antibiotics. Both partners require treatment.
Cholesterol The name for a group of blood fats. It includes LDL, or low-density lipoprotein, which is ‘bad’ cholesterol; HDL, or high-density lipoprotein, which is ‘good’ cholesterol; and triglycerides (TG). A high level of cholesterol in the blood is a major risk factor for heart attack and indirectly increases your risk of stroke.
Chocolate cysts Cysts which form on the ovaries in some women who have endometriosis. Also known as endometriomas.
Chorioamnioitis An infection inside the uterus affecting the membranes (called the chorion and amnion) which surround the amniotic fluid.
Chromosomal abnormality A different number or arrangement of chromosomes from the usual pattern.
Chromosomes The genetic structures within cells which contain our DNA (the material that carries genetic information). A normal cell contains 46 chromosomes. See also gene.
Chronic Something that persists or continues for at least six months.
Clinical guidelines Statements based on properly researched evidence which help healthcare professionals and patients to make decisions about medical care and treatments.
Clitoris A small organ under a fold of skin at the top of the vulva. The external part is about the size of a pea. When a woman is sexually aroused it swells with blood and produces feelings of sexual pleasure when stimulated.
Complementary therapy Treatments and therapies that are not part of conventional medicine. Examples include acupuncture, homeopathy and herbal medicine.
Complete miscarriage When all the tissue associated with a pregnancy has gone and the uterus is empty.
Complications Problems that develop after an operation, treatment or illness.
Conception When an egg is fertilised by sperm and then starts to grow in the womb.
Condition A state of being, like being healthy or fit, or having a problem, such as a heart problem.
Continence Having full control of the bladder and/or bowel. See also stress incontinence.
Contraception Ways to avoid becoming pregnant.
Corticosteroids A group of hormones which may be used to suppress the body’s immune response or to reduce inflammation. Also used during pregnancy in women who are thought may have their baby prematurely. They reduce the chance of the baby having problems from being born prematurely. See also steroids.
Counsellor A trained professional who helps people to make sense of feelings and issues.
Cystocele When the bladder bulges into the weakened wall of the vagina. A lump may be seen or felt.

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Dilatation and evacuation (D&E) Surgery using instruments to end the pregnancy.
Deep vein thrombosis (DVT) A blood clot that forms in a deep vein.
Delayed miscarriage/missed miscarriage/silent miscarriage A pregnancy that has ended although the fetus is still inside the uterus. Sometimes, because the fetus hasn’t developed, it can no longer be seen and there is just a fluid-filled sac inside the womb.
Delivery Birth of a baby and its afterbirth (see placenta). A baby may be delivered through the vagina or by caesarean section.
Diabetes A condition caused by high levels of glucose (a form of sugar) in the blood. The amount of glucose in your blood is controlled by a hormone called insulin.
Diagnosis The way a medical professional recognises a condition or disease.
Diathermy A surgical procedure to heat up and destroy body tissue or stop bleeding. Also known as electrocoagulation.
Discharge letter A letter a hospital doctor sends to a GP once treatment has finished telling the GP what has been done. The patient should be given a copy.
Disease An abnormal condition in the body causing harm.
Donor insemination When sperm from a donor is put into a woman’s vagina, cervix or womb to help start a pregnancy.
Doppler A method for measuring the flow of blood, for example through the umbilical cord during pregnancy.
Dysmenorrhoea Painful periods.
Dyspareunia Pain during or after sexual intercourse.

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Ectopic pregnancy When a fertilised egg (embryo) implants outside the womb (usually in one of the fallopian tubes).
Early miscarriage When a woman loses her baby in the first three months of pregnancy.
Early pregnancy assessment unit A clinic that specialises in problems in early pregnancy (under 12 weeks) where a woman receives medical care, counselling and treatment as required.
Eclampsia Seizures/fits that are a potentially life-threatening complication of pre-eclampsia.
Electrocoagulation See diathermy.
Embryo A fertilised egg.
Emergency caesarean delivery A caesarean delivery which was not planned during pregnancy. It is usually done because labour is not progressing normally or when the baby is unable to cope with labour and becomes distressed.
Endometriosis A condition where cells of the lining of the womb (the endometrium) are found elsewhere, usually around the pelvis and near the womb.
Endometritis Inflammation of the lining of the womb, causing discomfort or pain.
Endometrium The lining of the womb (uterus).
Enzyme A protein found in cells that speeds up chemical reactions in the body.
Epidural An anaesthetic injection into the space around the nerves in your back to numb the lower body.
Episiotomy A cut made through the vaginal wall and perineum to make more space to deliver the baby.
Erb’s palsy Damage to the nerves in the baby’s neck (brachial plexus injury) which reduces movement of and feeling in the baby’s arm.
Estrogen A female sex hormone produced by the ovaries as part of the menstrual cycle. It encourages an egg to mature and prepares the womb for a pregnancy. Levels vary during the menstrual cycle.
Evidence-based medicine A way of using reliable, objective, up-to-date evidence about how well different treatments or interventions work. It is also used to diagnose or predict the course of specific conditions.
Extended or frank breech The baby is bottom first, with the thighs against the chest and feet up by the ears. Most breech babies are in this position.
External cephalic version (ECV) Gentle pressure applied to the abdomen, if the baby is breech, by the obstetrician or midwife towards the end of pregnancy to help the baby turn in the uterus so it lays head first.

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Fallopian tubes The pair of hollow tubes leading from the womb to the fimbriae near the ovaries. Each month one ovary releases an egg, which moves down the fallopian tube into the womb. The fallopian tube is where the egg is fertilised by sperm in natural conception.
Fecundity Being fertile.
Female genital mutilation (FGM) The partial or total removal of a woman’s external genitals or other deliberate injury to her genital organs. It is illegal in the UK.
Fertilisation When a sperm enters an egg and an embryo forms. Natural fertilisation takes place inside a woman’s fallopian tubes. It can also take place outside the body, which is known as assisted conception. Techniques include IVF. See IVF and ART.
Fertility The ability to conceive a baby and, for a woman, to become pregnant.
Fertility drugs Treatment to encourage the ovaries to produce an egg. It is used during treatment for infertility.
Fertility problem/infertility/subfertility When a couple fail to conceive after having regular sexual intercourse for more than a year. ‘Regular’ is defined as two or three times a week.
Fetus An unborn baby.
Fetal medicine specialist A doctor who specialises in the growth, development, care and treatment of an unborn baby.
Fimbriae The fern-like ends of the fallopian tubes, near the ovaries.
First-degree tear A small skin-deep tear of the perineum during childbirth which usually heals naturally.
Flexed breech position The baby is laying bottom first in the womb, with the thighs against the chest and the knees bent.
Folic acid A B vitamin which reduces the risk of a baby being born with a spinal defect such as spina bifida. Ideally, a woman should take folic acid (400 micrograms) 3 months before conceiving. All women should take it for the first 12 weeks of pregnancy. A higher dosage (5 mg) is recommended if you are overweight, on epilepsy treatment, are diabetic or are having twin/triplets.
Follicle The part of the ovary where the egg develops.
Follicle-stimulating hormone (FSH) Hormones which help the development of follicles during a woman’s menstrual cycle and regulate sperm and hormone function in men.
Footling breech When a breech baby’s foot or feet are lying below its bottom.
Forceps delivery Smooth metal instruments like large spoons or tongs which are used to help deliver the baby. See also assisted birth.
Fourth-degree tear A tear during childbirth which extends to the anal canal as well as the rectum.

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Gamma globulin (IgG) A natural substance in the blood that protects against disease and infection. It is also used as a drug to boost immunity.
Gastroenteritis Inflammation of the stomach and intestines, usually resulting in diarrhoea or vomiting.
Gastrointestinal Relating to the stomach and intestine.
Gene A biological unit which passes on inherited information from parent to child, like facial characteristics.
Genetic Relating to, caused or controlled by genes.
Genetic counselling Discussions with a specialist to help you decide what to do if you, your partner or a close relative is found to carry an inheritable disease.
Genitals The sexual organs: in a woman, the vagina and vulva; and in a man, the penis and testicles.
Genital herpes An infection caused by the virus Herpes simplex (the virus that also causes cold sores). It is passed from one person to another by skin-to-skin contact. See also herpes.
Gestation The time between conception and birth, when the fetus grows and develops inside the mother’s womb.
Gestational age The age of the baby in the womb, measured in weeks from the first day of the woman’s last menstrual period. A normal pregnancy lasts between 37 and 41 completed weeks, so a baby’s gestation is usually around 40 weeks.
Gestational diabetes A form of diabetes triggered during pregnancy.
Gonadotrophin-releasing hormone agonist A synthetic hormone-like drug which holds back the production of eggs.
Gonadotrophins Hormones that help ovulation in women and the production of sperm in men. See also follicle-stimulating hormone, human chorionic gonadotrophin and luteinising hormone.
Graduated elastic compression stocking An elasticated stocking which helps reduce swelling from deep vein thrombosis (DVT).
Group B streptococcus (GBS) A bacterium that is commonly present within the vagina. However, it can cause a serious infection in a newborn baby. It can also cause infection in the womb (endometritis).
Guideline Recommendations for good medical practice. They help patients and their medical teams make decisions about care (like those produced by the RCOG) and are developed by specialist teams who look at the best evidence available about care or treatment for a particular condition.
Gynaecologist A doctor who treats medical conditions and diseases that affect women and their reproductive organs.

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Highly active antiretroviral therapy (HAART or ART) A combination of drugs used to treat people with HIV. It works by blocking the action of the virus and the progress of the infection.
Haematologist A doctor who specialises in the diagnosis and treatment of diseases of the blood.
Haemolysis Breaking down of red blood cells in the body.
Haemorrhage Very heavy bleeding. In pregnancy it is called different names depending on the stage of pregnancy. It can happen:
  • Before 24 weeks of pregnancy (threatened miscarriage or miscarriage if the pregnancy is lost)
  • After 24 weeks of pregnancy (antepartum haemorrhage)
  • Immediately after birth (postpartum haemorrhage)
HELLP syndrome A combined liver and blood clotting disorder which is a complication of pre-eclampsia.
Heparin A type of anti-coagulant medication that is given by injection.
Herpes A family of viruses which cause a range of infections including chickenpox (Herpes zoster, or varicella), cold sores and genital herpes (Herpes simplex).
High-dependency unit A ward or area in a hospital that provides care for people who need intensive observation or treatment.
Hormone treatment The use of hormones to treat disease or to replace hormones no longer produced by the body.
Hormones Naturally occurring substances made in the body which control the activity of normal cells. They include: follicle stimulating hormone, gonadotrophins, human chorionic gonadotrophin, luteinising hormone, estrogen, progesterone, prostaglandin.
Human chorionic gonadotrophin (hCG) A hormone made by the placenta which shows up in a woman’s blood or urine if she is pregnant. May be used as part of assisted conception to help eggs to mature and to help an embryo attach to the womb.
Human immunodeficiency virus (HIV) A viral infection which attacks the body’s immune system, making it hard to fight off other infections. HIV is passed through contact with body fluids (blood, semen, vaginal fluid and breast milk).
Hyperprolactinaemia A disorder which increases the normal level of the hormone prolactin. It can cause irregular periods and fertility problems.
Hypertension Raised blood pressure.
Hypotension Low blood pressure.
Hypothalamus A small structure at the base of the brain which regulates body functions such as temperature and appetite.
Hysterectomy An operation to remove the cervix and womb, carried out through a cut on the abdomen (abdominal hysterectomy) or the vagina (vaginal hysterectomy). The ovaries can be removed at the same time, if necessary.
Hysterosalpingo-contrast-sonography An ultrasound test of the fallopian tubes or the womb, using fluid injected through the cervix.
Hysterosalpingogram (HSG) An X-ray of the fallopian tubes or the womb, using fluid injected through the cervix.
Hysteroscopy and endometrial biopsy A small operation which opens the entrance to the womb (cervix) to remove tissue from the lining of the womb (the endometrium).

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Immune system The way the body defends itself against infection, disease and outside substances.
Immunity Protection against infectious diseases through the action of the immune system. You can become immune to some diseases by catching them. Vaccinations also provide immunity.
Immunotherapy Treatment to prevent or change the response of the immune system.
Implantation The process through which an embryo attaches to the lining of the womb.
In vitro fertilisation (IVF) A technique where eggs are collected from a woman and fertilised with a man’s sperm outside the body. Usually one or two embryos are then transferred to the womb. If one or more of them implants successfully, the woman becomes pregnant.
Incomplete miscarriage When a miscarriage has started but some tissue remains in the uterus.
Incontinence Not having full control over the bladder and/or bowel. Problems with incontinence can range from slight to severe. See also stress incontinence.
Induction of labour When labour is started artificially.
Infectious Conditions which can be passed from person to person by micro-organisms like viruses or bacteria.
Infertility/subfertility/fertility problem When a couple fail to conceive after having regular sexual intercourse for more than a year. ‘Regular’ is defined as two or three times a week.
Informed decision/choice Providing enough quality information about a suggested treatment to help a patient decide whether to go ahead. This information must be balanced, up to date, evidence-based and given in a way that the patient can understand.
Infusion A way of putting a drug or fluid into the bloodstream through a needle at a steady rate over a period of time.
Intensive care unit A specialist unit within a hospital that provides extra care for seriously ill people.
Interstitial cystitis Inflammation of the bladder wall.
Intracytoplasmic sperm injection (ICSI) A form of assisted conception in which a single sperm is injected into an egg.
Intrapartum During birth.
Intrauterine contraceptive device (IUCD) A small device fitted into the womb to prevent conception. Made of plastic and copper, it has one or two soft threads at the end which emerge through the cervix into the top of the vagina.
Intrauterine insemination (IUI) A form of assisted conception which places sperm into a woman’s womb through the cervix.
Intrauterine system (IUS) A small T-shaped contraceptive device that is fitted into the womb. Made of plastic, it slowly releases the hormone progestogen.
Intravenous drip (IV drip) Fluids put into a vein to rehydrate the body. Drips contain different combinations of minerals and chemicals, for example sugar and carbohydrate to provide extra energy.
Invasive A medical procedure when a cut is made to the body or an instrument is inserted.
Irritable bowel syndrome (IBS) A chronic disorder involving abdominal pain, bloating and changes in bowel habits, such as diarrhoea. It is caused by an overactive bowel.

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Karyotype A record of the complete set of your chromosomes.
Karyotyping A procedure to produce a karyotype using a blood or tissue sample. It is used to check for abnormalities in the chromosomes.
Kidney The body’s two kidneys keep fluids balanced by filtering the blood. Waste products are then excreted as urine.
Klumpe’s paralysis Reduced movement in the baby’s arm from damage to nerves in the baby’s neck (see brachial plexus injury).

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Laparoscopic ovarian drilling/diathermy A surgical treatment for polycystic ovary syndrome to improve irregular periods. Small cuts are made in the abdomen and an electrical current is used to destroy a tiny part of the ovaries.
Labour The stages of childbirth. Labour is divided into three stages; first, second and third.
Laparoscopy Keyhole surgery involving up to four small cuts in the abdomen. A telescopic microscope (called a laparoscope) is inserted into the body to help diagnosis or treatment.
Laparotomy A cut up to 14 inches long giving surgeons access to the abdomen.
Laxatives Medication to open bowels.
Libido Sexual desire.
Luteinising hormone (LH) A natural hormone released during the menstrual cycle to help stimulate ovulation.

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Major placenta praevia A low-lying placenta entirely covering the cervix. See also placenta praevia.
Medical abortion A way of ending a pregnancy by using medicines. See also abortion and surgical abortion.
Meningitis Inflammation in the brain caused by a virus or bacteria.
Menopause The time when a woman’s periods stop, usually around 50 years of age. See also menstrual cycle.
Menstrual cycle The monthly process in which an egg develops and the lining of the womb is prepared for possible pregnancy. If the egg is not fertilised, it is reabsorbed back into the body and the lining of the womb (the endometrium) is shed. This is known as a period or menstruation. The cycle is controlled by hormones and on average a cycle lasts 28 days.
Meta-analysis A way of combining and contrasting results from different studies with the aim of finding underlying patterns common to all.
Miscarriage The unplanned ending of a pregnancy before 23 completed weeks.
Midtrimester The middle stage of pregnancy, between 13 and 26 weeks.
Molar pregnancy A rare condition where the placenta overgrows and the embryo does not form correctly.
Multiple pregnancy When a woman is carrying more than one baby, e.g. twins or triplets.
Musculoskeletal The body’s support structure: the bones, ligaments, joints and muscles.

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Neonatal unit An intensive care unit designed with special equipment to care for premature or seriously ill newborn babies.
Neonatalologist A doctor who specialises in caring for newborn babies.


Obstetrician A doctor who specialises in the care of pregnant women.
Oedema Swelling in any part of the body.
Oestrogen See estrogen.
Oligohydramnios Too little fluid (amniotic fluid) surrounding the baby in the uterus.
Oocyte donation When eggs are donated to help another women become pregnant.
Ovarian hyperstimulation syndrome (OHSS) A potentially serious complication of fertility treatment, particularly of IVF. Symptoms are abdominal swelling or bloating, nausea and vomiting.
Ovaries A pair of organs (each about the size of an almond) in a woman’s pelvis. They produce follicles from which eggs develop.
Ovulation The process by which the ovaries produce and release an egg each month. Ovulation usually takes place around 10–16 days before a period.
Oxytocics Drugs that stimulate the womb to contract.

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Peer review An assessment of the content and quality of a report or body of research by a group of individuals who have a range of expertise in a particular field.
Paediatrician A doctor who specialises in the care of babies, children and teenagers.
Pelvic Of the pelvis.
Pelvic congestion Swollen pelvic veins.
Pelvic examination,
A check to feel the size and position of the womb and other reproductive organs to rule out any abnormality or problem.
Pelvic floor muscles Layers of muscle which support the bladder and other organs in the pelvis.
Pelvic inflammatory disease (PID) An infection in the womb, fallopian tubes and/or pelvis caused by infections such as chlamydia and gonorrhoea.
Pelvic pain Pain in the lower abdomen or pelvis.
Pelvis The bony structure at the lower part of the abdomen.
Perineum The area of skin between the vagina and the anus.
Period A bleed from the vagina between every 3 to 5 weeks which forms part of the menstrual cycle (see menstrual cycle).
Peritoneum The tissue that lines the abdominal wall and covers most of the organs in the abdomen.
Pessaries A medication or device which is placed in the vagina.
Physiotherapy Special exercises and physical activities to improve body function and strength.
Pituitary gland A gland in the brain that produces hormones.
Placenta An organ which develops in the womb linking the baby with the mother’s system. It is delivered after the baby, when it is known as the afterbirth.
Placenta accreta When the placenta is attached to the muscle of the womb and does not come away properly after the birth.
Placenta praevia A condition where the placenta covers all or part of the cervix. If the placenta does not move sufficiently it may be necessary to perform a caesarean. See also major placenta praevia.
Platelets Specialised cells necessary for blood clotting.
Polycystic ovaries Ovaries which have at least twice as many developing follicles as normal ovaries in the early part of the menstrual cycle.
Polycystic ovary syndrome (PCOS) A condition which can affect a woman’s menstrual cycle, fertility, hormones and aspects of her appearance. It can also affect long-term health.
Polyhydramnios Too much fluid (amniotic fluid) surrounding the baby in the uterus.
Postnatal The baby’s condition after birth.
Postpartum The mother’s condition after childbirth.
Postpartum haemorrhage Heavy blood loss after the delivery of the baby.
Pre-eclampsia (also known as toxaemia) A condition that occurs in the second half of pregnancy, associated with high blood pressure and protein in the urine.
Pregnancy test A test on a sample of urine or blood to confirm whether a woman is pregnant. The test works by detecting the presence of a pregnancy hormone.
Preterm labour Labour that happens before 37 weeks of pregnancy.
Preterm premature rupture of membranes When a pregnant woman’s waters break before 37 weeks of pregnancy.
Progesterone A hormone produced as a result of ovulation. It prepares the lining of the womb to enable a fertilised egg to implant there.
Progestogen A synthetic hormone, similar to progesterone. It thickens the mucus around the cervix, making it difficult for sperm to get into the womb or for a fertilised egg to implant in the womb.
Prolactin The hormone which is responsible for producing breast milk.
Prolapse Where the bladder, womb or bowel pushes through the wall of the vagina.
Prostaglandin The hormone that makes the womb contract during labour. Synthetic prostaglandins can be used to induce labour or in medical abortion to end a pregnancy.
Proteinuria Protein in the urine.
Pubic, pubis The area around the bone at the front of the pelvis.
Pudendal block A local anaesthetic injection inside the vagina.
Pulmonary embolus Part of a blood clot (DVT) which breaks off and travels in the blood stream and becomes stuck in the lung.

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Randomised controlled trial (RCT) A study which tests the effectiveness and safety of treatments or procedures as fairly and objectively as possible. By randomly assigning patients to different treatments for the same problem, the results can be assessed equally with the aim of discovering the best possible procedure for the condition.
Rectocele When the rectum bulges into the weakened wall of the vagina. A lump may be seen or felt.
Rectum The part of the large intestine which stores solid waste until it leaves the body through the anus.
Recurrent miscarriage When a woman loses three or more babies before 23 completed weeks.
Reproductive organs The parts of the male and female body needed to create and sustain a pregnancy.
Reproductive years In women, the time from the start of menstrual periods (menarche) to the menopause.
Retrovirus A type of virus. HIV is a retrovirus. See also HAART and antiretroviral therapy.
RhD antigen A protein on the red blood cells of 85% of people in the UK. These people are known as RhD positive. People who do not have the protein are described as RhD negative. See also blood group.
Risk The chance that an activity or hazard will give rise to harm. Risk is generally given in terms of numerical odds (1 in 10) or percentages (10%).
Royal College of Obstetricians and Gynaecologists (RCOG) The professional body which oversees the medical education, training and examination of obstetricians and gynaecologists in the UK and many places overseas. It sets internationally recognised standards and produces clinical guidelines for treatment and care.
Rupture of membranes The medical term for the breaking of waters in pregnancy.

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Screening A test or set of tests to check for a condition in a person who shows no symptoms, but who may be at risk (perhaps because of their age or sexual behaviour, for example).
Sanitary pad A disposable pad of absorbent material used to collect blood during menstruation and after childbirth.
Scientific evidence Information gathered in a systematic way to confirm or disprove a particular idea. Growing understanding may result in established practices being changed.
Second-degree tear A tear during childbirth which affects the muscle of the perineum as well as the skin, and usually requiring stitches.
Second stage of labour The period when the cervix is fully dilated until the birth. This is the time when the woman will start pushing.
Semen The fluid that contains sperm.
Severe pre-eclampsia When pre-eclampsia has progressed and treatment is required or the baby needs to be delivered.
Sexually transmitted infection (STI) An infection that is passed on through close physical contact during sex. Some STIs have no symptoms, so it is important to be tested if you think you have been at risk. See also chlamydia, genital herpes and HIV.
Shoulder dystocia A situation during birth when the baby’s head has been born but one of the shoulders becomes stuck behind the mother’s pelvic bone, preventing the birth of the baby’s body.
Sickle cell disease (SCD) An inherited condition in which red blood cells, which carry oxygen around the body, develop abnormally.
Special care baby unit A specialist unit in a hospital to care for premature babies.
Speculum A plastic or metal instrument used to separate the walls of the vagina to show or reach the cervix.
Sperm The male reproductive cell which fertilises a woman’s eggs. Men usually have millions of sperm in their semen.
Spina bifida A condition which affects the unborn baby in the early stages of pregnancy. Spina bifida causes damage to the spinal cord and nerves.
Spontaneous vaginal birth The natural birth of a baby through the vaginal canal without assistance.
Sporadic A ‘one-off’ event.
Sterilisation Permanent contraception for women (see tubal occlusion) and men (see vasectomy).
Steroids A group of natural or synthetic hormones. See also corticosteroids.
Stillbirth When a baby is born dead after the 23rd completed week of pregnancy.
Stool (or faeces) The waste matter discharged in a bowel movement.
Stress incontinence Leaking urine during everyday activities like coughing, laughing or exercising. This usually happens because the muscles that support the bladder are too weak.
Surgical abortion A type of abortion using suction instruments or D&E to end a pregnancy. See also abortion and medical abortion.
Sutures Stitches.
Symphysis fundal height A measure of the size of the uterus used to monitor a baby’s growth and development during pregnancy.
Symptom A specific medical sign of a condition, illness or disease.
Syndrome A collection of different signs and symptoms that are all part of the same underlying medical condition.
Systematic review A review of evidence from a number of studies on a particular topic. The review uses standardised methods to analyse results and assess conclusions.

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Thrombophilia A blood clotting abnormality which tends to run in families, whereby the blood is more likely to clot than usual.
Tachycardia A rapid heart beat.
Tampon A tube of absorbent material that fits into the vagina to absorb the menstrual blood.
Temperature The degree of hotness or coldness of a body or an environment.
Term Between 37 and 42 weeks of pregnancy.
Third-degree tear A tear during childbirth which extends downwards from the vaginal wall and perineum to the anal sphincter, the muscle that controls the anus.
Threatened miscarriage Bleeding before 24 weeks of pregnancy which occurs without harm to the baby.
Thrombosis A clot in a blood vessel.
Thrush See vaginal thrush.
To open bowels To go to the toilet to pass solid waste.
Tocolysis Treatments used to delay or prevent early labour.
Toxaemia See pre-eclampsia.
Transabdominal scan A scan where the probe is moved across the abdomen.
Transvaginal scan A scan where the probe is placed inside the vagina.
Transverse position When the baby is lying across the womb.
Trimester A three-month period of time. Pregnancy is divided into three trimesters:
  • First trimester – up to around 13 weeks
  • Second trimester – to around 13 to 26 weeks
  • Third trimester – around 27 to 40 weeks
Tubal occlusion An operation which blocks, seals or cuts the fallopian tubes. Also known as sterilisation. It is a permenant method of contraception for women.

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Ultrasound High-frequency sound waves used to provide images of the body, tissues and internal organs.
Umbilical cord (umbilicus) The cord that connects a mother’s blood system with a baby’s (through its navel) and which is cut after the birth.
Urethra The tube through which urine empties out of the bladder.
Urethracele When the tissues that hold the urethra in place weaken, causing it to move and put pressure on the vagina, sometimes pushing through the wall of the vagina.
Urine Excreted fluids containing waste products of the body.
Urodynamics Tests to assess how the bladder is working.
Uterus (also known as womb) The organ where a baby develops during pregnancy. Made of muscle, it is hollow, stretchy and about the size and shape of an upside-down pear. It sits between the bladder and the rectum in a woman’s pelvis.

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Vagina The canal leading from the vulva to the cervix.
Vaginal discharge Any vaginal secretion except menstrual bleeding.
(Normal) vaginal discharge A clear or whitish fluid that comes from the vagina or cervix.
(Abnormal) vaginal discharge An abnormal smelling yellow or green discharge which should be assessed by a doctor.
Vaginal examination – internal A check to feel the size and position of the vagina and cervix to check there isn’t any abnormality or problem. This may be carried out using a speculum.
Vaginal swab Similar to a cotton bud, but smaller and rounder. Some have a small plastic loop at the end instead of a cotton tip. It is wiped over the vagina to collect samples of fluid to check for infection.
Vaginal thrush An infection caused by a yeast known as Candida albicans. Symptoms include redness and itching around the genital area and unusual vaginal discharge.
Varicella The medical name for chickenpox. See chickenpox.
Vas deferens The tube which carries sperm from the testicles to the penis.
Vasectomy A permanent method of contraception for men. It blocks, seals or cuts the tube (the vas deferens) which carries sperm from the testicles to the penis. Also known as sterilisation.
Vein A blood vessel that takes blood towards the heart.
Venous thrombosis A blood clot that forms in a vein.
Ventouse delivery A way of helping deliver a baby by using suction through a special cup placed on the baby’s head.
Virus A micro-organism which invades living cells in order to grow or reproduce. Viruses cause many infections, from the common cold, chickenpox and measles to HIV.
Vulva The area surrounding the opening of the vagina. It includes the inner and outer vaginal lips (the labia) and the clitoris.

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Weak cervix When the cervix (the neck of the womb) opens too early in pregnancy, in the second trimester, and without contractions. Used to be known as ‘incompetent cervix’.
White cell Cells in the lymphatic and blood systems of the body which fight infection. They are part of the body’s immune system.
White cell count A count to measure the number of white blood cells.
Womb See uterus.


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Read the most common queries put to the College by patients
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