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a form of complementary and alternative medicine that involves inserting thin needles through the skin at specific points on the body to control pain and other symptoms.


a foreign substance to the body's immune system that may cause an allergic reaction.

Alzheimer's disease

a brain disease that cripples the brain's nerve cells over time and destroys memory and learning. It usually starts in late middle age or old age and gets worse over time. Symptoms include loss of memory, confusion, problems in thinking, and changes in language, behavior, and personality.

amniotic fluid

clear, slightly yellowish liquid that surrounds the unborn baby (fetus) during pregnancy. It is contained in the amniotic sac.


the use of medicine to prevent the feeling of pain or another sensation during surgery or other procedures that might be painful.


a thin or weak spot in an artery that balloons out and can burst.


a recurring pain or discomfort in the chest that happens when some part of the heart does not receive enough blood. It is a common symptom of coronary heart disease, which occurs when vessels that carry blood to the heart become narrowed and blocked due to atherosclerosis. Angina feels like a pressing or squeezing pain, usually in the chest under the breast bone, but sometimes in the shoulders, arms, neck, jaws, or back. Angina is usually is brought on by exertion, and relieved within a few minutes by resting or by taking prescribed angina medicine.


drugs used to fight many infections caused by bacteria. Some antibiotics are effective against only certain types of bacteria; others can effectively fight a wide range of bacteria. Antibiotics do not work against viral infections.


blood proteins made by certain white blood cells called B cells in response to germs or other foreign substances that enter the body. Antibodies help the body fight illness and disease by attaching to germs and marking them for destruction.


a name for a category of medications used to treat depression.


drugs that are used to prevent or relieve the symptoms of hay fever and other allergies by preventing the action of a substance called histamine, which is produced by the body. Histamine can cause itching, sneezing, runny nose, watery eyes, and sometimes can make breathing difficult. Some of these drugs are also used to prevent motion sickness, nausea, vomiting, and dizziness. Since they may cause drowsiness as a side effect, some of them may be used to help people go to sleep.


anticancer drugs that can stop or slow down biochemical reactions in cells.


the body opening from which stool passes from the lower end of the intestine and out of the body.

anxiety disorder

serious medical illness that fills people's lives with anxiety and fear. Some anxiety disorders include panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, social phobia (or social anxiety disorder), specific phobias, and generalized anxiety disorder.


blood vessels that carry oxygen and blood to the heart, brain and other parts of the body.


disease when fatty deposits clog the walls of the arteries.


swelling, redness, warmth, and pain of the joints, the places where two bones meet, such as the elbow or knee. There are more than 100 types of arthritis. The two most common types of arthritis are osteoarthritis and rheumatoid arthritis.

assisted reproductive technology

technology that involves procedures that handle a woman's eggs and a man's sperm to help infertile couples conceive a child.


a chronic disease of the lungs. Symptoms include cough, wheezing, a tight feeling in the chest, and trouble breathing.


a disease in which fatty material is deposited on the wall of the arteries. This fatty material causes the arteries to become narrow and it eventually restricts blood flow.


blood proteins made by the body's immune system that are meant to neutralize and destroy germs or other foreign substances but instead attack healthy cells of the body.

autoimmune disease

disease caused by an immune response against foreign substances in the tissues of one's own body.

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microorganisms that can cause infections.

bacterial vaginosis (BV)

the most common vaginal infection in women of childbearing age, which happens when the normal bacteria (germs) in the vagina get out of balance, such as from douching or from sexual contact. Symptoms include vaginal discharge that can be white, gray, or thin and have an odor; burning or pain when urinating; or itching around the outside of the vagina. There also may be no symptoms.




the organ in the human body that stores urine. It is found in the lower part of the abdomen.

blood glucose level

also called blood sugar level, it is the amount of glucose, or sugar, in the blood. Too much glucose in the blood for a long time can cause diabetes and damage many parts of the body, such as the heart, blood vessels, eyes, and kidneys.

blood transfusion

the transfer of blood or blood products from one person (donor) into another person's bloodstream (recipient). Most times, it is done to replace blood cells or blood products lost through severe bleeding. Blood can be given from two sources, your own blood (autologous blood) or from someone else (donor blood).

body mass index

a measure of body fat based on a person's height and weight.


inflammation of the main air passages (bronchi) to your lungs. It causes cough, shortness of breath, and chest tightness.

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a unit of energy-producing potential in food.


a term for diseases in which abnormal cells in the body divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymphatic system, which is a network of tissues that clears infections and keeps body fluids in balance.

celiac disease

a digestive disease that damages the small intestine and interferes with absorption of nutrients from food. When people with celiac disease eat foods containing gluten, their immune system responds by damaging the small intestine.


the lower, narrow part of the uterus (womb). The cervix forms a canal that opens into the vagina, which leads to the outside of the body.

cesarean section or C-section

procedure where the baby is delivered through an abdominal incision. Also called cesarean delivery or cesarean birth.


treatment with anticancer drugs.

chicken pox

a disease caused by the varicella-zoster virus, which results in a blister-like rash, itching, tiredness, and fever.


an alternative medical system that takes a different approach from standard medicine in treating health problems. The goal of chiropractic therapy is to normalize this relationship between your body's structure (mainly the spine) and its function. Chiropractic professionals use a type of hands-on therapy called spinal manipulation or adjustment.


a common sexually transmitted disease (STD). Most people have no symptoms, but chlamydia can cause serious damage a women's reproductive organs. When a woman does have symptoms, they may include thin vaginal discharge and other symptoms similar to gonorrhea like burning when urinating. Long-term irritation may cause lower abdominal pain, inflammation of the pelvic organs, and pelvic inflammatory disease (PID).


a fatty substance present in all parts of the body. It is a component of cell membranes and is used to make vitamin D and some hormones. Some cholesterol in the body is produced by the liver and some is derived from food, particularly animal products. A high level of cholesterol in the blood can help cause atherosclerosis and coronary artery disease. In the blood, cholesterol is bound to chemicals called lipoproteins. Cholesterol attached to low-density lipoprotein (LDL) harms health and is often called bad cholesterol. Cholesterol attached to high-density lipoprotein (HDL) is good for health and is often called good cholesterol.


long-lasting, such as a chronic illness or chronic disease.


the result of chronic liver disease, where the liver is scarred and no longer functions properly. This causes many complications, including build up of fluid in the abdomen, bleeding disorders, increased pressure in the blood vessels and brain function disorders.

cleft lip or palate

birth defects that affect the upper lip and the hard and soft palates of the mouth. Features range from a small notch in the lip to a complete fissure or groove, extending into the roof of the month and nose. These features may occur separately or together.

colon cancer

cancer in the inner lining of the colon. The colon is the part of the digestive tract that removes water from feces before the feces leaves the body through the anus. Most colon cancers start as noncancerous growths called polyps.

colorectal cancer

cancer of the colon or rectum is also called colorectal cancer. See colon cancer.


thick, yellowish fluid secreted from breast during pregnancy, and the first few days after childbirth before the onset of mature breast milk. Also called first milk, it provides nutrients and protection against infectious diseases.


infrequent or hard stools or difficulty passing stools.

coronary artery disease

also called coronary heart disease. It is the most common type of heart disease that results from atherosclerosis — the gradual buildup of plaques in the coronary arteries, the blood vessels that bring blood to the heart. This disease develops slowly and silently, over decades. It can go virtually unnoticed until it produces a heart attack.

cystic fibrosis (CF)

one of the most common serious genetic (inherited) diseases. One out of every 400 couples is at risk for having children with CF. CF causes the body to make abnormal secretions leading to mucous build-up. CF mucous build-up can impair organs such as the pancreas, the intestine and the lungs.


also called "dropped bladder," when the bladder drops into or out of the vagina. A cystocele happens when the muscles or tissues of the pelvic area are weak or damaged and can no longer support the pelvic organs.

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when a person believes something that is not true and that person keeps the belief even though there is strong evidence against it. Delusions can be the result of brain injury or mental illness.


a group of symptoms caused by disorders that affect the brain. Symptoms may include memory loss, confusion, personality changes, and difficulty with normal activities like eating or dressing. Dementia has many causes, including Alzheimer's disease and stroke.

dental dam

a square, thin piece of latex that can be placed over the anus or the vagina before oral sex.


term used to describe an emotional state involving sadness, lack of energy and low self-esteem.



a disease in which blood glucose (blood sugar) levels are above normal. There are two main types of diabetes. Type 1 diabetes is caused by a problem with the body's defense system, called the immune system. This form of diabetes usually starts in childhood or adolescence. Type 2 diabetes is the most common form of diabetes. It starts most often in adulthood.



birth control device made of a thin flexible disk, usually made of rubber, that is designed to cover the cervix to prevent the entry of sperm during sexual intercourse.


passing frequent and loose stools that can be watery. Acute diarrhea goes away in a few weeks. Diarrhea becomes chronic when it lasts longer than 4 weeks.

dietary fiber

coarse fibrous substances found in grains, fruits, and vegetables. Dietary fiber is generally not digested but helps move food through the digestive tract. Eating dietary fiber helps prevent many long-term illnesses, including type 2 diabetes, cardiovascular diseases, and certain gastrointestinal diseases.

DNA test

a lab test in which a patient's DNA is tested. DNA is a molecule that has a person's genetic information and is found in every cell in a person's body.

Down syndrome

Down syndrome is the most frequent genetic cause for mild to moderate mental retardation and related medical problems. It is caused by a chromosomal abnormality. For an unknown reason, a change in cell growth results in 47 instead of the usual 46 chromosomes. This extra chromosome changes the orderly development of the body and brain.

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eating disorder

eating disorders, such as anorexia nervosa, bulimia nervosa, and binge-eating disorder, involve serious problems with eating. This could include an extreme decrease of food or severe overeating, as well as feelings of distress and concern about body shape or weight.

ectopic pregnancy

a pregnancy that is not in the uterus. It happens when a fertilized egg settles and grows in a place other than the inner lining of the uterus. Most happen in the fallopian tube, but can happen in the ovary, cervix, or abdominal cavity.


a group of conditions in which the skin becomes inflamed, forms blisters, and becomes crusty, thick, and scaly. Eczema causes burning and itching and may occur over a long period of time. Atopic dermatitis is the most common type of eczema.

electrocardiogram (ECG or EKG)

an external, noninvasive test that records the electrical activity of the heart.

endometrial cancer

cancer that develops from the endometrium, or the inner lining of the uterus (womb).


a condition in which tissue that normally lines the uterus grows in other areas of the body, usually inside the abdominal cavity, but acts as if it were inside the uterus. Blood shed monthly from the misplaced tissue has no place to go, and tissues surrounding the area of endometriosis may become inflamed or swollen. This can produce scar tissue. Symptoms include painful menstrual cramps that can be felt in the abdomen or lower back, or pain during or after sexual activity, irregular bleeding, and infertility.


during labor a woman may be offered an epidural, where a needle is inserted into the epidural space at the end of the spine, to numb the lower body and reduce pain. This allows a woman to have more energy and strength for the end stage of labor, when it is time to push the baby out of the birth canal.


a physical disorder that involves recurrent seizures. It is caused by sudden changes in how the brain works.


This is a procedure where an incision is made in the perineum (area between the vagina and the anus) to make the vaginal opening larger in order to prevent the area from tearing during delivery.


tube that connects the throat with the stomach.


a group of female hormones that are responsible for the development of breasts and other secondary sex characteristics in women. Estrogen is produced by the ovaries and other body tissues. Estrogen, along with progesterone, is important in preparing a woman's body for pregnancy.

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fallopian tube(s)

part of the female reproductive system, one of a pair of tubes connecting the ovaries to the uterus.


a feeling of lack of energy, weariness or tiredness.

fetal alcohol spectrum disorders (FASD)

a term used to describe the full range of harmful effects that can occur when a fetus is exposed to alcohol.


body temperature is raised above normal and is usually a sign of infection or illness.

fibromyalgia (FM)

a disorder that causes aches and pain all over the body, and involves tender points on specific places on the neck, shoulders, back, hips, arms, and legs that hurt when pressure is put on them.

follicle-stimulating hormone (FSH)

a hormone produced by the pituitary gland. In women, it helps control the menstrual cycle and the production of eggs by the ovaries.

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a condition where the body is not able to process galactose (a sugar), which makes up half of the sugar (called lactose) found in milk. When galactose levels become high, body organs and the central nervous system can be damaged. In newborns, the condition is found when first breastfeeding and can cause jaundice and other problems.


solid material that forms in the gallbladder or common bile duct. Gallstones are made of cholesterol or other substances found in the gallbladder. They may occur as one large stone or as many small ones, and they may vary from the size of a grain of sand to a golf ball.


the functional and physical unit of heredity made up of DNA, which has a specific function and is passed from parent to offspring

gestational diabetes

diabetes that occurs during pregnancy.

gestational high blood pressure

also called gestational hypertension; high blood pressure that happens only during pregnancy. Gestational high blood pressure raises your risk for health problems during pregnancy such as preeclampsia.


a cell, group of cells, or organ that makes chemicals and releases them for use by other parts of the body or to be excreted. The pituitary gland, for example, makes growth hormone, which stimulates cells to grow and divide. Sweat glands excrete water, salts, and waste to help cool down the body.


a sexually transmitted disease that often has no symptoms. However, some women have pain or burning when urinating; yellowish and sometimes bloody vaginal discharge; bleeding between menstrual periods; heavy bleeding with periods; or pain when having sex. Untreated gonorrhea can cause serious and permanent health problems like pelvic inflammatory disease (PID).

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when a person who is awake senses something that is not real. Examples of hallucinations are hearing voices when no one is speaking, seeing something that doesn't exist, or smelling something that is not present.

heart disease

a number of abnormal conditions affecting the heart and the blood vessels in the heart. The most common type of heart disease is coronary artery disease, which is the gradual buildup of plaques in the coronary arteries, the blood vessels that bring blood to the heart. This disease develops slowly and silently, over decades. It can go virtually unnoticed until it produces a heart attack.

hemorrhagic stroke

type of stroke caused by a weakened blood vessel that bursts, causing bleeding in the brain.


veins around the anus or lower rectum that are swollen and inflamed.

hepatitis B

a serious disease caused by a virus that attacks the liver. The virus, which is called hepatitis B virus (HBV), can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death. You get hepatitis B by direct contact with the blood or body fluids of an infected person; for instance, you can become infected by having sex or sharing needles with an infected person. A baby can get hepatitis B from an infected mother during childbirth.

herpes simplex virus (HSV)

a virus that causes blisters and sores mainly around the mouth and genitals. There are two types. Type 1 is the most common and causes sores around the mouth, or cold sores. It is transmitted by infected saliva. Type 2 causes sores mainly on the genitals and is transmitted sexually.

high blood pressure


human immunodeficiency virus (HIV) is the virus that infects and destroys the body's immune cells and causes a disease called AIDS, or Acquired Immunodeficiency Syndrome. AIDS occurs in the most advanced stage of HIV infection, when a person's T-cell count goes below 200 and he or she becomes ill with one of the health problems common in people with AIDS. HIV and AIDS infection is lifelong—there is no cure, but there are many medicines to fight both HIV infection and the infections and cancers that come with it.


red and sometimes itchy bumps on the skin, usually caused by an allergic reaction to a drug or a food.


substance produced by one tissue and conveyed by the bloodstream to another to affect a function of the body, such as growth or metabolism.

human T-cell lymphotropic virus type 1 or type 2 (HTLV 1-2)

viruses that infect T cells, a type of white blood cell, and can cause leukemia and lymphoma. HTLV 1-2 is spread by sharing syringes or needles, through blood transfusions or sexual contact, and from mother to child during birth or breastfeeding.


also called high blood pressure, it is having blood pressure greater than 140 over 90 mmHg (millimeters of mercury). Long-term high blood pressure can damage blood vessels and organs, including the heart, kidneys, eyes, and brain.


a focused state of concentration used to reduce pain. With self-hypnosis, you repeat a positive statement over and over. With guided imagery, you create relaxing images in your mind.



surgery to remove the uterus.

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immune system

a complex system in the body that recognizes and responds to potentially harmful substances, like infections, in order to protect the body.


the inability to control the flow of urine from the bladder, called urinary incontinence, or the escape of stool from the rectum, called fecal incontinence.


a condition in which a couple has problems conceiving, or getting pregnant, after 1 year of regular sexual intercourse without using any birth control methods. If a woman keeps having miscarriages, it's also called infertility. Infertility can be caused by a problem with the man or the woman, or both.


used to describe an area on the body that is swollen, red, hot, and in pain.

inflammatory bowel disease

long-lasting problems that cause irritation and ulcers in the gastrointestinal tract. The most common disorders are ulcerative colitis and Crohn's disease.


chemicals used to control or kill insects.


not being able to sleep.


one of many hormones that helps the body turn the food we eat into energy and helps store energy to be used later. People with diabetes mellitus, a condition in which the body does not make enough insulin, might need to inject themselves with insulin to help their bodies' cells work properly.


also known as the bowels, or the long, tube-like organ in the human body that completes digestion or the breaking down of food. They consist of the small intestine and the large intestine.

intrauterine device

a small device that is placed inside a woman's uterus by a health care provider, which prevents pregnancy by changing the environment of the uterus (or womb).


an important mineral involved in creating and using energy, including moving oxygen throughout the body.

ischemic stroke

a blockage of blood vessels supplying blood to the brain, causing a decrease in blood supply.

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a yellowing of the skin and the whites of the eyes, caused by too much bilirubin in the blood. While not a disease, jaundice can signal a liver or gallbladder problem. Newborns can develop jaundice, which is only temporary and goes away.

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kidney stones

hard mass developed from crystals that separate from the urine and build up on the inner surfaces of the kidney.

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lactose intolerance

a digestive disorder in which the body cannot digest or absorb lactose, a type of sugar found in milk and other dairy products.


a metal that can make infants and young children sick.


sexual drive.


a harmful bacteria found in some refrigerated and ready-to-eat foods that can cause early delivery or miscarriage.


the largest body organ, the liver has many jobs, including changing food into energy and cleaning alcohol and poisons from the blood. The liver also makes bile, a yellowish-green liquid that helps with digestion.

low birth weight

having a weight at birth that is less than 2500 grams, or 5 pounds, 8 ounces.


luteinizing hormone

a hormone that triggers ovulation and stimulates the corpus luteum (empty follicle) to make progesterone.

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male circumcision

the surgical removal of the skin covering the tip of the penis. In the United States and in many countries around the world, circumcision is done on newborn boys for religious, cultural, or medical reasons. Circumcision may protect against infections, including sexually transmitted infections (STIs). Male circumcision is different from female genital cutting (FGC), which is sometimes called female circumcision. FGC is the piercing, cutting, removing, or sewing closed all or part of a girl's or woman's external genitals for no medical reason.




infection which causes inflammation of the membranes covering the brain and spinal cord.

menopausal hormone therapy (MHT)

replaces the hormones that a woman's ovaries stop making at the time of menopause, easing symptoms like hot flashes and vaginal dryness. MHT is associated with serious risks, including breast cancer, heart disease and stroke. Women who choose to use MHT should use the lowest dose that helps for the shortest time needed.


the transition in a woman's life when production of the hormone estrogen in her body falls permanently to very low levels, the ovaries stop producing eggs, and menstrual periods stop for good.


the blood flow from the uterus that happens about every 4 weeks in a woman.


Metabolism refers to all of the processes in the body that make and use energy, such as digesting food and nutrients and removing waste through urine and feces.


a medicine that kills microbes such as bacteria or a virus. It is usually a gel, cream, or foam that is put on the vagina or rectum before sex to stop HIV or other sexually transmitted infections (STIs).


a medical condition that usually involves a very painful headache, usually felt on one side of the head. Besides intense pain, migraine also can cause nausea and vomiting and sensitivity to light and sound. Some people also may see spots or flashing lights or have a temporary loss of vision.


an unplanned loss of a pregnancy. Also called a spontaneous abortion.

multiple sclerosis

also called MS, a disorder of the brain and spinal cord that causes decreased nerve function associated with the formation of scars on the covering of nerve cells. Symptoms range from numbness to paralysis and blindness. A person with MS slowly loses control over his or her body.

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necrotizing enterocolitis

necrotizing enterocolitis occurs when the lining of the intestinal wall dies and the tissue falls off.It mainly affects premature infants or sick newborns. The cause for this disorder is unknown. But it is thought that a decrease in blood flow to the bowel keeps the bowel from making mucus that protects the gastrointestinal tract. Bacteria in the intestine may also be a cause.


the protruding part of the breast that extends and becomes firmer upon stimulation. In breastfeeding, milk travels from the milk sinuses through the nipple to the baby.


any food substance that provides energy or helps build tissue.

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see obesity.


having too much body fat. People with a body mass index of 30 or higher are obese.


a bone disease that is characterized by progressive loss of bone density and thinning of bone tissue, causing bones to break easily.

ovary (ovaries)

part of a woman's reproductive system, the ovaries produce her eggs. Each month, through the process called ovulation, the ovaries release eggs into the fallopian tubes, where they travel to the uterus, or womb. If an egg is fertilized by a man's sperm, a woman becomes pregnant and the egg grows and develops inside the uterus. If the egg is not fertilize, the egg and the lining of the uterus is shed during a woman's monthly menstrual period.


the release of a single egg from a follicle that developed in the ovary. It usually occurs regularly, around day 14 of a 28-day menstrual cycle.

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Pap test

a test that finds changes in the cells of the cervix. The test can find cancer or cells that can turn into cancer. To perform a Pap test, a health care provider uses a small brush to gently scrape cells from the cervix for examination under a microscope.


an organism that lives on or in a host organism and gets its food from or at the expense of its host.

pelvic exam

during this exam, the doctor or nurse practitioner looks for redness, swelling, discharge, or sores on the outside and inside of the vagina. A Pap test tests for cell changes on the cervix. The doctor or nurse practitioner will also put two fingers inside the vagina and press on the abdomen with the other hand to check for cysts or growths on the ovaries and uterus. STD tests may also be done.

pelvic inflammatory disease (PID)

an infection of the female reproductive organs that are above the cervix, such as the fallopian tubes and ovaries. It is the most common and serious problem caused by sexually transmitted diseases (STDs). PID can cause ectopic pregnancies, infertility, chronic pelvic pain, and other serious problems. Symptoms include fever, foul-smelling vaginal discharge, extreme pain, and vaginal bleeding.


the phase in a woman's reproductive lifecycle leading up to menopause. Menopause is reached when a woman hasn't had a period for 12 months in a row. Before that point, during perimenopause, a woman's body slowly makes less of the hormones estrogen and progesterone. This causes some women to have symptoms such as hot flashes and changes in their periods. Many women go through it in their 40s and 50s.


any substance or mixture of substances intended for preventing, destroying, or repelling any pest. It also includes herbicides, fungicides, and various other substances used to control pests.

phenylketonuria (PKU)

an inherited disorder in which the body cannot process a portion of the protein called phenylalanine (Phe), which is in almost all foods. If the Phe level gets too high, the brain can become damaged. All babies born in the United States are now tested for PKU soon after birth, making it easier to diagnose the disease and to treat it early.


during pregnancy, a temporary organ joining the mother and fetus. The placenta transfers oxygen and nutrients from the mother to the fetus, and permits the release of carbon dioxide and waste products from the fetus. The placenta is expelled during the birth process with the fetal membranes.

placental abruption

when the placenta separates from the uterine wall before delivery, which can mean the fetus doesn't get enough oxygen.


a buildup of fat, cholesterol and other substances that accumulate in the walls of the arteries.


a severe inflammation of the lungs in which the alveoli, or tiny air sacs in the lungs, are filled with fluid. This may cause a decrease in the amount of oxygen that the blood can absorb from air breathed into the lung. Pneumonia is usually caused by infection but may also be caused by radiation treatment, allergy, or irritation of lung tissue by inhaled substances. It may involve part or all of the lungs.

polycystic ovary syndrome (PCOS)

a health problem that can affect a woman's menstrual cycle, ability to have children, hormones, heart, blood vessels, and appearance. With PCOS, women typically have high levels of androgens or male hormones, missed or irregular periods, and many small cysts in their ovaries.

postpartum depression (PPD)

a serious condition that requires treatment from a health care provider. With this condition, feelings of the baby blues (feeling sad, anxious, afraid, or confused after having a baby) do not go away or get worse.


a mineral that plays important roles in muscle contraction, the beating of the heart, and the sending of nerve impulses.

preconception health

a woman's health before she becomes pregnant. It involves knowing how health conditions and risk factors could affect a woman or her unborn baby if she becomes pregnant.


also known as toxemia, it is a syndrome occurring in a pregnant woman after her 20th week of pregnancy that causes high blood pressure and problems with the kidneys and other organs. Symptoms include sudden increase in blood pressure, too much protein in the urine, swelling in a woman's face and hands, and headache.

premature birth

premenstrual syndrome (PMS)

a group of symptoms linked to the menstrual cycle that occur in the week or two weeks before menstruation. The symptoms usually go away after menstruation begins and can include acne, breast swelling and tenderness, feeling tired, having trouble sleeping, upset stomach, bloating, constipation or diarrhea, headache or backache, appetite changes or food cravings, joint or muscle pain, trouble concentrating or remembering, tension, irritability, mood swings or crying spells, and anxiety or depression.

preterm birth

also called premature birth, it is a birth that occurs before the 37th week of pregnancy.

preterm labor

labor that occurs before 37 completed weeks of pregnancy.

primary ovarian insufficiency (POI)

a reproductive health problems that occurs when a woman's ovaries stop working normally before she is 40. POI is not the same as early menopause. Some women with POI still get a period now and then. But ovulation problems can make getting pregnant hard for women with POI.


a female hormone produced by the ovaries. Progesterone, along with estrogen, prepares the uterus (womb) for a possible pregnancy each month and supports the fertilized egg if conception occurs. Progesterone also helps prepare the breasts for milk production and breastfeeding.


a hormone that increases during pregnancy and breastfeeding. It stimulates the human breast to produce milk. Prolactin also helps inhibit ovulation.

prostate gland

a gland in a man's reproductive system. It makes and stores seminal fluid. This fluid is released to form part of semen.


any of a group of large molecules that contain primarily carbon, hydrogen, oxygen, and nitrogen. Proteins are essential to the structure and function of all living cells. Examples of proteins in the body include enzymes, antibodies, and some hormones.


time when the body is changing from the body of a child to the body of an adult. This process begins earlier in girls than in boys, usually between ages 8 and 13, and lasts 2 to 4 years.

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treatment using radiation to destroy cancer cells.

restless legs syndrome (RLS)

a disorder that causes a powerful urge to move your legs. Your legs become uncomfortable when you are lying down or sitting. Some people describe it as a creeping, crawling, tingling or burning sensation. Moving makes your legs feel better, but not for long.

rheumatoid arthritis (RA)

form of arthritis that causes pain, swelling, stiffness and loss of function in your joints. It can affect any joint but is common in the wrist and fingers. If one hand has RA, the other one usually does too. It's an autoimmune disease. This means the arthritis is caused by your immune system attacking your body's own tissues. RA can affect body parts besides joints, such as your eyes, mouth and lungs.

Rh factor

a protein found on most people's red blood cells. If you do not have the protein, you are Rh negative. Most pregnant women who are Rh negative need treatment to protect the fetus from getting a blood disease that can lead to anemia.


also called German measles. Rubella virus causes rash, mild fever, and arthritis. If a woman gets rubella while she is pregnant, she could have a miscarriage or her baby could be born with serious birth defects.

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saturated fat

fat such as butter, solid shortening, lard, and fatback. It is recommended that people avoid eating saturated fat, which increases the risk of certain long-term illnesses, such as coronary artery disease.


a drug that calms a person and allows her or him to sleep.


uncontrollable contractions of muscles that can result in sudden movement or loss of control, also known as convulsions.


the fluid (which contains sperm) a male releases from his penis when he becomes sexually aroused or has an orgasm.

sexually transmitted infections (STIs)

diseases that are spread by sexual activity. Also called sexually transmitted diseases (STDs).

sickle cell anemia

a blood disorder passed down from parents to children. It involves problems in the red blood cells. Normal red blood cells are round and smooth and move through blood vessels easily. Sickle cells are hard and have a curved edge. These cells cannot squeeze through small blood vessels. They block the organs from getting blood. Your body destroys sickle red cells quickly, but it can't make new red blood cells fast enough — a condition called anemia.

sleep apnea

a disorder involving brief interruptions of breathing during sleep.


a mineral that is used in regulating the amount of water in the body. Sodium also plays important roles, along with potassium, in muscle contraction, the beating of the heart, and the sending of nerve impulses. Sodium is an ingredient of table salt.

spina bifida

spina bifida is the most common of all birth defects. Its name means clef spine, or a failure of a fetal spine to close the right way when it is developing before birth. It occurs very early in pregnancy, roughly three to four weeks after conception, before most women know that they are pregnant. Any woman can have an affected pregnancy. Most women who bear a child with Spina bifida have no family history of it.


when a fetus dies during birth, or when the fetus dies during the late stages of pregnancy when it would have been otherwise expected to survive.


stoppage of blood flow to an area of the brain, causing permanent damage to nerve cells in that region. A stroke can occur either because an artery is clogged by a blood clot (called ischemic stroke) or an artery tears and bleeds into the brain. A stroke can cause symptoms such as loss of consciousness, problems with movement, and loss of speech.

sudden infant death syndrome (SIDS)

the diagnosis given for the sudden death of an infant under one year of age that remains unexplained after a complete investigation. Because most cases of SIDS occur when a baby is sleeping in a crib, SIDS is also commonly known as crib death. Most SIDS deaths occur when a baby is between 1 and 4 months of age.

symptothermal method

a method of pregnancy planning or birth control that combines certain aspects of the calendar, the basal body temperature, and the cervical mucus methods. It takes into account all these factors as well as other symptoms a woman might have, such as slight cramping and breast tenderness.


a sexually transmitted disease which may or may not have symptoms. Symptoms in the first stages can include painless sores on the genitals, anus, or mouth and enlarged lymph nodes in the area around the sore. Syphilis can be cured with antibiotics. If left untreated, syphilis can permanently damage the brain, nerves, eyes, heart, blood vessels, liver, bones, and joints. This damage includes paralysis (not being able to move or feel a part of the body), numbness, blindness, dementia, and even death.

systemic lupus erythematosus

an autoimmune disease that can cause inflammation and damage to the joints, skin, kidneys, heart, lungs, blood vessels, and brain.

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testicle (testis)

the male sex gland. There are a pair of testes behind the penis in a pouch of skin called the scrotum. The testes make and store sperm, and make the male hormone testosterone.


a yeast infection, caused by the fungus Candida albicans, of the mouth and throat. It's hallmark is white patches in the mouth. It can also occur in the gastrointestinal tract and vagina, and causes some types of diaper rash in infants.


The thyroid is a small gland in the neck that makes and stores hormones that help regulate heart rate, blood pressure, body temperature, and the rate at which food is converted into energy.

tourette's syndrome

a brain-based disorder that starts in childhood in which a person makes involuntary movements and sounds (called tics).


an infection caused by the parasite named Toxoplasma gondii that can invade tissues and damage the brain, especially in a fetus and in a newborn baby. Symptoms include fever, fatigue, headache, swollen lymph glands, and muscle aches and pains. Can be contracted by touching the hands to the mouth after gardening, cleaning a cat's litter box, or anything that came into contact with cat feces; or by eating raw or partly cooked meat, or touching the hands to the mouth after touching raw or undercooked meat.

trans fat

a type of unsaturated fat. Foods made with partially hydrogenated or hydrogenated oils contain trans fat. Food manufacturers use trans fat to prolong the shelf life of processed food. Some trans fats occur naturally in meat and dairy products from animals such as cattle, goats, and sheep. Eating trans fats increases the risk of certain long-term illnesses, such as coronary artery disease.


a type of fat in the blood stream and fat tissue. High triglyceride levels (above 200) can contribute to the hardening and narrowing of arteries.

trisomy 18

a condition in which a baby is conceived with three copies instead of the normal two copies of chromosome #18. Children with this condition have multiple malformations and mental retardation due to the extra chromosome #18. Some of the problems include: low birth weight, small head, small jaw, malformations of the heart and kidneys, clenched fists with abnormal finger positioning, and malformed feet. The mental retardation is severe. Ninety five percent of children with this condition die before their first birthday.


a disease caused by bacteria that usually affects your lungs. Tuberculosis (TB) bacteria is spread through the air from one person to another. If someone with TB of the lungs or throat coughs or sneezes, people nearby who breathe in the bacteria can get TB. If your body can't stop the bacteria from growing, you will develop TB disease.

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a painless test that uses sound waves to produce images of the organs and structures of the body on a screen. Also called sonography.

umbilical cord

connected to the placenta and provides the transfer of nutrients and waste between the woman and the fetus.


the tube that releases urine from the body.

urinary tract infection

an infection anywhere in the urinary tract, or organs that collect and store urine and release it from your body (the kidneys, ureters, bladder, and urethra). An infection occurs when microorganisms, usually bacteria from the digestive tract, cling to the urethra (opening to the urinary tract) and begin to multiply.

uterine contractions

during the birthing process, a woman's uterus tightens, or contracts. Contractions can be strong and regular (meaning that they can happen every 5 minutes, every 3 minutes, and so on) during labor until the baby is delivered. Women can have contractions before labor starts; these are not regular and do not progress, or increase in intensity or duration.

uterine fibroids

common, benign (noncancerous) tumors that grow in the muscle of the uterus, or womb. Fibroids often cause no symptoms and need no treatment, and they usually shrink after menopause. But sometimes fibroids cause heavy bleeding or pain, and require treatment.


a woman's womb, or the hollow, pear-shaped organ located in a woman's lower abdomen between the bladder and the rectum.

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the muscular canal that extends from the cervix to the outside of the body. Its walls are lined with mucus membranes and tiny glands that make vaginal secretions.


Inflammation of the vagina, often caused by infection. Symptoms can include vaginal itching, burning, pain, and discharge.


small microscopic organisms that often cause disease.


the external female genital organ. It has five parts, including the urinary opening and the opening to the vagina.

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breathing with difficulty, with a whistling noise. Wheezing is a symptom of asthma.

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yeast infections

a common infection in women caused by an overgrowth of the fungus Candida. It is normal to have some yeast in your vagina, but sometimes it can overgrow because of hormonal changes in your body, such as during pregnancy, or from taking certain medications, such as antibiotics. Symptoms include itching, burning, and irritation of the vagina; pain when urinating or with intercourse; and cottage cheese-looking vaginal discharge.

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