Health Library A to Z

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• Cuts and Wounds of the Mouth and Lips
Kids can get cuts and wounds in their mouth and on their lips when they are playing or doing sports. Learn how to use first aid for these injuries, and when to get medical care.

• Diet and Diabetes
It's important to learn about correct meal-planning when your child has diabetes. The type and amount of food your child eats affects their blood sugar levels.

• Infant of a Mother with Diabetes
When a mother has diabetes, her baby is at risk for problems. Read on to learn more.

• Infectious Mononucleosis (Mono) in Teens and Young Adults
Infectious mononucleosis is a contagious illness. It’s common in teens and young adults.

• Knowing When to Seek Treatment for Your Child
Common symptoms of a potential emotional, behavioral, or developmental problem include poor grades in school, withdrawal from friends and family, and insomnia.

• Major Depression in Teens
Major depression goes beyond the day's normal ups and downs. It involves a teen's body, mood, and thoughts. It can affect and disrupt eating, sleeping, or thinking patterns.

• Making Family Fitness Fun
Activity can help prevent heart disease, cancer, and stroke. It can also lessen feelings of depression, and boost confidence. As children get older, they often reduce their physical activity. Because of this, making activity a family priority is key.

• Male Conditions
Detailed information on the most common male genitourinary conditions

• Male Growth and Development
Detailed information on male growth and development

• Male Physical Development
Detailed information on male growth and development

• Malocclusion in Children
Malocclusion is when a child’s teeth become crooked or crowded. The child may also have a problem with their bite. That means the teeth of the upper jaw don’t meet normally with the teeth of the lower jaw when the jaw is closed.

• Managing Poor Weight Gain in Your Breastfed Baby
Sometimes a breastfed baby will gain weight more slowly than they should. Read on to learn some helpful tips on how to deal with this.

• Many Youngsters Suck Their Thumbs
Young children often suck on their thumbs. It's perfectly normal. But some parents worry about it.

• Marfan Syndrome in Children
Marfan syndrome is a genetic  disorder that affects the body's connective tissue. Connective tissue holds the body's cells, organs, and other tissue together. Connective tissue is also important in growth and development.

• Mastoiditis in Children
Mastoiditis is a complication of a middle ear infection. Read on to learn more about symptoms, diagnosis, and treatment.

• Measles (Rubeola) in Children
Measles (rubeola) is a respiratory illness caused by a virus. It causes a red, blotchy rash. It’s a very contagious illness.

• Measles, Mumps, and Rubella (MMR) Vaccine
The MMR vaccine is given in 2 doses--at 12 to 15 months and at 4 to 6 years, or at least 1 month after the first dose.

• Meckel Diverticulum
Meckel diverticulum is a small pouch in the wall of the intestine. It’s near where the small and large intestines meet. This condition is the most common birth defect of the digestive system. It happens to about 1 in 50 babies.

• Meconium Aspiration
Meconium aspiration happens when a newborn breathes in a mixture of meconium and amniotic fluid. Amniotic fluid is the liquid that surrounds the baby in the womb. Meconium is the baby's first stool, or poop, which is sticky, thick, and dark green. It is typically passed in the womb during early pregnancy and again in the first few days after birth.

• Medical Genetics: Chromosome Studies
When a chromosome is abnormal, it can cause health problems in the body. Tests called studies can look at chromosomes to see what type of problem a person has.

• Medical Genetics: DNA Studies for Single Gene Defects
To look for single gene defects, healthcare providers look at the DNA to see if it has any errors in it. Errors are known as mutations.

• Medical Genetics: Getting Genetic Services for Your Child
Genetic services are programs that help support families and children with genetic disorders.

• Medical Genetics: How Genetic Testing Is Used
Genetic testing can help find diseases that run in a family or don't yet have symptoms.

• Medical Genetics: Mosaicism
Mosaicism is when a person has 2 or more genetically different sets of cells in his or her body.

• Medical Genetics: Multifactorial Inheritance
Multifactorial inheritance is when more than 1 factor causes a trait or health problem, such as a birth defect or chronic illness. Genes can be 1 factor, but other things that aren't genes can play a part, too.

• Medical Genetics: Teratogens
A teratogen is something that can cause or raise the risk for a birth defect in a baby. They are things that a mother may be exposed to during her pregnancy.

• Medical Genetics: Types of Genetic Changes
Genetic changes come in 2 main types: chromosome abnormalities and single-gene defects.

• Medicine Rashes in Children
Medicine rashes are the body’s reaction to a certain medicine. The type of rash that occurs depends on the type of medicine that is causing it. Rashes can range from mild to severe.

• Megaloblastic Anemia in Children
Anemia is a problem in which there are not enough red blood cells or hemoglobin. Hemoglobin is the part of red blood cells that carries oxygen throughout the body. In megaloblastic anemia, the bone marrow, where the cells are formed, makes fewer cells. And the cells that are formed don’t live as long as normal.

• Megaureter in Children
Megaureter is a ureter that is much wider than normal. A megaureter may not drain urine normally. This can lead to infections and kidney damage.

• Meningitis in Children
Meningitis is most often caused by a bacterial or viral infection that moves into the cerebral spinal fluid (CSF).

• Meningococcal Infection in Children
Meningococcal infections are not common, but they can be fatal. They occur most often in late winter and early spring. Children are more often affected, but the illnesses also occur in teens and adults.

• Menstrual Cramps (Dysmenorrhea) in Teens
Menstrual cramps (dysmenorrhea) are severe, painful cramps that occur with menstruation.

• Menstrual Disorders
Detailed information on the most common menstrual conditions, including premenstrual syndrome (PMS), premenstrual dysphoric disorder, amenorrhea, dysmenorrhea, and menorrhagia

• Metatarsus Adductus in Children
Metatarsus adductus is a common foot deformity noted at birth. It causes the front half of the child's foot (forefoot) to turn inward.

• Microcephaly in Children
Microcephaly is a condition where a baby's head is much smaller than normal. It is most often present at birth (congenital). Most children with microcephaly also have a small brain and an intellectual disability. Some children with small heads have normal intelligence.

• Micropenis in Children
A micropenis is a penis that is smaller than normal. A penis length of less than 0.75 inches is considered micropenis.

• Milk Allergy Diet for Children
Helpful information on helping your child follow a milk-free diet, including tips for reading food labels.

• Minor Cuts, Scrapes, and Skin Wounds
Detailed information on minor cuts, scrapes, and skin wounds in children

• Minor Injuries Overview
Children's days are filled with running, jumping, bicycling, sports, and other fun activities that keep them active and on-the-go" from morning until night. Along with the fun comes an occasional cut

• Mitochondrial Inheritance- Leber Hereditary Optic Neuropathy
Detailed information on mitochondrial inheritance and Leber's optic atrophy.

• Mold
Detailed information on mold allergy, including possible sources of mold inside and outside the home

• Molluscum Contagiosum in Children
Molluscum contagiosum is a viral skin disease that causes small pink or skin-colored bumps on your child’s skin. It is not harmful and usually does not have any other symptoms. The virus is inside the bumps and is mildly contagious. These bumps usually clear over time.

• Mood Disorders in Teens
Anyone can feel sad or depressed at times. But mood disorders are more intense. They are harder to handle than normal feelings of sadness. Read on to learn more about these types of disorders in teens.

• Mosaic Down Syndrome
Detailed information on mosaic Down syndrome, including the chances for it to happen again in a family

• Motor Vehicle Safety Overview
Detailed information on motor vehicle safety, including installing and using child safety seats and booster seats

• Mouthguards
Mouthguards are important to help protect your child's mouth and teeth from serious injury.

• Moving Your Toddler from Crib to Bed
Moving your child from the crib to a first bed is a milestone event. But more than the bittersweet emotional concerns, your priorities will be safety and a healthy sleep routine.

• Mumps in Children
Mumps is a very contagious viral illness that infects the pair of salivary glands in front of the ears. Cases of mumps in the U.S. happen much less often since the mumps vaccine has been used.

• Muscle and Joint Injuries
Detailed information on muscle and joint injuries, including prevention

• Myasthenia Gravis (MG) in Children
Myasthenia gravis (MG) is a disorder that causes weakness in muscles around the body. This happens because antibodies destroy some of the places where nerves and muscles meet. It mostly affects the eyes, mouth, throat, arms, and legs.

• Newborn Measurements
Your newborn will be weighed in the hospital and at all check-ups. In most cases, metric units are used to record babies' weight. This chart will help you convert the metric unit grams (g) to pounds (lb) and ounces (oz).

• Superficial Injuries of the Face and Head- Overview
During a child's day, minor injuries may happen during play and sports activities. The face and head are especially at risk for cuts and scrapes.

• Turner Syndrome (Monosomy X) in Children
A detailed look at Turner syndrome, a genetic disorder that occurs in girls.