Pregnancy

Stenosis

Spinal stenosis is a medical condition in which the spinal canal narrows and compresses the spinal cord and nerves. This is usually due to the spinal degeneration that commonly occurs with aging. It can also sometimes be caused by osteoporosis, spinal disc herniation, or a tumor.

Spinal stenosis may affect the cervical, thoracic or lumbar spine.

Symptoms include:

  • Pain
  • Weakness
  • Tingling of the legs

Surgery for spinal stenosis is the most common spinal operation in people over the age of 50. However, spinal stenosis caused by developmental narrowing of the spinal canal may occur in people in their 20s and 30s.

Operations used to treat stenosis include:

  • Anterior Cervical Discectomy and Fusion — A small incision in the front of the neck is used to access the upper spine. The ruptured or herniated disc is removed and replaced with a small bone plug, which eventually grows to connect the two adjacent vertebrae.
  • Cervical Corpectomy — Part of the vertebra and discs are removed and replaced with a bone graft or a metal plate and screws to support the spine.
  • Decompressive Laminectory — The roof of the vertebrae, called the lamina, is surgically removed. The procedure also may include removing part of the disc or fusing the vertebrae (spinal fusion).
  • Foramenotomy — The area where nerve roots leave the spinal canal, called the foramen, is removed. This procedure can be performed using a minimally invasive approach with an endoscope, an instrument that allows the surgeon to see inside the body through a tiny incision. The surgeon can then use other tiny incisions to perform the surgery, avoiding the discomfort and muscle atrophy associated with the traditional open technique that uses a large incision.
  • Laminoplasty — The compressive bone in the back of the neck is gently lifted off of the spinal cord creating a new “roof” over the spinal cord and nerve roots. This procedure effectively decompresses the spinal cord over multiple segments without the need for fusion or hardware. It also minimizes the chance of spinal instability or deformity that may result from the traditional laminectomy procedure.
  • Laminotomy — Only a small portion of the lamina is removed.
  • Medial Facetectomy — Part of the bone structure in the spinal canal, called the facet, is removed.
  • Cervical Disc Replacement — Instead of fusing the affected area, the natural disc material is replaced with a metal and plastic prosthesis that maintains or restores the motion segment. This will hopefully prevent degeneration of the next disc level.

Cervical Stenosis

Stenosis in the neck, also called the cervical spine, affects the upper part of the body including the arms and hands. Stenosis is the narrowing of the bony canal that protects the spinal cord and its branching nerves to the point where it injures the spinal cord or nerves.

This may be caused by a number of conditions including:

  • Bone spurs
  • Rupture of the spinal discs

Cervical stenosis may cause pain, numbness, or weakness in the legs. The pain may move from one part of the body to another but is often most noticeable in the neck.

If the stenosis is severe and is not responding to other treatment methods, surgery to widen the spinal canal may be necessary. Because bone continues to deteriorate, additional treatment may be needed several years after even successful surgery.

Lumbar Stenosis

Stenosis in the lower back is called lumbar stenosis. It is often characterized by radiating pain in the buttocks and legs.

Frequently people afflicted with lumbar stenosis have varying degrees of low back discomfort. The pain typically occurs most often during activities and is relieved by resting, sitting or bending forward. In some cases, the pain is centralized in the lower legs and feet. In severe cases, it also can impact continence (bowel and bladder control) and sexual function.

The initial treatment for stenosis is to treat the symptoms rather than the condition itself. These treatments include:

  • Rest
  • Posture changes, such as lying with the knees drawn up to the chest or leaning forward while walking, may relieve the pressure on the nerves
  • Medication such as aspirin or ibuprofen to relieve inflammation and pain
  • Physical therapy
  • Losing weight
  • Corticosteroid injections to reduce inflammation and relieve pain
  • A cervical collar

If several months of treatment have not improved the symptoms, and if the stenosis is severe, surgery to widen the spinal canal may be necessary. Because bone continues to deteriorate, additional treatment may be needed several years after even successful surgery.

Pregnancy Care

Pregnancy is broken into three time periods — called trimesters. Most women feel differently, both physically and mentally, during each trimester.

In addition to weight and body shape, other alterations in your body chemistry and function also take place.

  • The heart works harder
  • Your temperature registers slightly higher
  • Body secretions increase
  • Joints and ligaments are more flexible
  • Hormones are altered

Mood changes also are common, resulting from a combination of hormonal changes and greater fatigue, as well as normal anxiety over body image, sexuality, finances, partner roles and impending parenthood.

Each trimester is marked by specific fetal developments. Full term pregnancy is considered 40 weeks and infants delivered before the end of 37th week are considered premature. Premature infants may have problems with their growth and development, as well as difficulties in breathing and digesting.

First Trimester — 0 to 13 Weeks

The first trimester is the most crucial to your baby’s development. During this period, your baby’s body structure and organ systems develop. Most miscarriages and birth defects occur during this period.

Your body also undergoes major changes during the first trimester. These changes often cause a variety of symptoms, including:

  • Nausea
  • Fatigue
  • Breast tenderness
  • Frequent urination

Although there are common symptoms of pregnancy, every woman has a different experience. For example, while some may experience an increased energy level during this period, others may feel very tired and emotional.

Second Trimester — 13 to 26 Weeks

The second trimester of pregnancy is often called the “golden period” because many of the unpleasant effects of early pregnancy have ended. During the second trimester, you’re likely to experience:

  • Decreased nausea
  • Better sleep patterns
  • Increased energy level

However, during this period you may experience a whole new set of symptoms and feelings, such as back pain, abdominal pain, leg cramps, constipation and heartburn.

You will probably hear your baby’s heartbeat for the first time at around 12 weeks. An ultrasound is typically performed around 19 weeks. And, somewhere between 16 weeks and 20 weeks, you may feel your baby’s first fluttering movements.

Third Trimester — 26 to 40 Weeks

You have now reached your final stretch of pregnancy and are probably very excited and anxious for the birth of your baby. Some of the physical symptoms you may experience during this period include:

  • Shortness of breath
  • Hemorrhoids
  • Urinary incontinence
  • Varicose veins
  • Sleeping problems

Many of these symptoms arise from the increase in the size of your uterus, which expands from approximately 2 ounces before pregnancy to 2.5 pounds at the time of birth.

Prenatal Care

Expert prenatal care ensures that both you and your baby are as healthy as possible throughout your pregnancy. Once you think that you are pregnant, contact your doctor to make an appointment and establish your prenatal care schedule.

Many factors affect the number of visits you have, and the same formula does not work for everyone. Your schedule may vary depending on your personal health as well as your doctor’s preference. Additional prenatal care may be necessary if you have any preexisting medical conditions, such as diabetes, and/or complications arise during your pregnancy. However, if all things are going well with your pregnancy, visits are planned around key pregnancy developments and certain tests that need to be performed. In addition, visits are a time for your doctor to give you important information as your pregnancy progresses.

The goal of prenatal care is not only to provide the best care for you and your unborn child, but also to prepare you for birth. During prenatal visits, tests are performed on you and your baby to assess any potential risks, to treat any maternal or fetal complications, and to monitor the growth and development of your baby.

Create a Birth Plan

You also will be provided with a Birth Plan, a form asking about your preferences for delivery. This promotes communication with your health care provider and helps them meet your individual needs. You will complete your Birth Plan and discuss it with your health care provider at your 34 to 36 week visit. Make photocopies of your Birth Plan. Give one to your health care provider to put in your medical record and bring one with you when you come to the hospital in labor.

Danger Signs

Although numerous symptoms are a normal part of pregnancy, there are certain danger signs that may indicate problems with your pregnancy. You should notify your doctor immediately if you experience any of the following:

  • Persistent vomiting
  • Chills or fever
  • Continuous pain
  • Burning with urination
  • Blurred vision
  • Continuous headache
  • Sudden swelling of the hands or face
  • Five or more uterine contractions per hour
  • Decreased fetal movements
  • Leaking of fluid from the vagina (blood or water). If you have vaginal bleeding at any time during your pregnancy, have someone call your doctor immediately.

Miscarriage and Abortion

First trimester uterine aspiration — sometimes called vacuum or suction aspiration — is performed as an elective abortion, as treatment after a miscarriage and for pregnancy termination due to fetal anomalies. This procedure can be performed in a one-day office visit if the pregnancy is less than 14 weeks. It involves gentle suction to remove pregnancy tissue.

The procedure is generally performed in a doctor’s office with local anesthesia and pain-relieving medications. Patients may take oral anti-anxiety medications to help relax but these medications should not be taken until a doctor instructs you to do so. Intravenous (IV) sedation or general anesthesia is usually not offered for this procedure.

You should not eat or drink for two hours before your appointment. The entire visit should take about three hours if you’re less than 12 weeks pregnant. If you’re 12 to 14 weeks pregnant, your visit will be five to six hours because of the additional time required to soften or dilate your cervix.

Someone must be available to take you home after the procedure since you shouldn’t drive a car or ride a taxi or public transit alone after taking pain and anti-anxiety medications.

Before the procedure, you’ll learn about uterine aspiration, undergo an exam and receive oral medications, which may include pain relief and anti-anxiety medications. If you’re 12 to 14 weeks pregnant, you may receive a medication called misoprostol to soften your cervix for dilation. Misoprostol takes two to three hours to take effect. It is recommended that you bring reading material for this waiting period.

During uterine aspiration, you’ll be awake, but relaxed. If you wish, someone may accompany you during the entire procedure, which takes about 15 minutes. During the procedure, your doctor will:

  • Place a speculum to view inside your vagina
  • Clean the cervix with gauze soaked in soap
  • Apply local anesthesia to numb the cervix
  • Dilate your cervix, the opening to the uterus, with tapered rods
  • Insert a straw-like flexible tube or cannula through the cervix into the uterus
  • Apply gentle suction, using either a hand-held or electric device, to the other end of the tube to aspirate or remove pregnancy tissue

At the end of the procedure, you may feel a cramp similar to a menstrual cramp in your uterus as it shrinks to its normal size.

After the procedure, you’ll rest for a few minutes. You may experience some cramping and spotting. When you feel able, you may get dressed. A health educator will review instructions for care after the procedure and possible complications. You’ll be given antibiotics to prevent infection.

You can expect to return to normal activities, such as work and school, the next day.

Unless you experience complications or have concerns, there’s no need to return for follow up appointments.

Uterine aspiration is one of the safest medical procedures. Although rare, possible complications include:

  • A blood clot in the uterus that can cause pain or require a repeat aspiration
  • Infection, which is generally easily identified and treated
  • A tear in the cervix that can be easily repaired with suture
  • Perforation
  • Retained pregnancy tissue requiring repeat aspiration
  • Excessive bleeding requiring a transfusion

Complications are less frequent and less serious than those associated with giving birth.

Fertility

Most people plan to have children at some point in their lives, and many assume that when they are ready they will be able to conceive without trouble. However, that is not always the case. Infertility refers to the biological inability of a person to contribute to conception. There are many biological causes of infertility, some which may be bypassed with medical intervention.

Infertility is when a couple has not conceived after months of contraceptive-free intercourse if the female is under the age of 34. Infertility in a couple can be due to either the woman or the man, not necessarily both. Infertility is not a sexual disorder.

Approximately 10 to 15 percent of North American couples who want children are infertile. Worldwide it is estimated that one in seven couples have problems conceiving.

There are many options available to help women and men address infertility. Medications and surgery are the traditional approaches to correcting infertility. Modern technology has created a new group of fertility solutions called assisted reproductive technologies, or ART, in which a portion of the conception process may occur outside the body. The most common ART is in vitro fertilization (IVF) but a variety of others have been developed to address specific fertility problems.

These procedures include:

  • In Vitro Fertilization
  • Intra-Uterine Insemination
  • Ovulation Induction
  • Male Treatments

Infertility in Women

A woman’s age is probably the most significant factor related to her ability to conceive. While many women today are waiting until later in life to attempt pregnancy, the ovary’s ability to produce normal, healthy eggs declines with age, increasing the risk of chromosomal abnormalities and unsuccessful implantation.

The likelihood for successful pregnancy generally begins to decrease in women in their early 30s or possibly in their late 20s. While this decline is initially quite minimal, it begins to accelerate at about age 38 and fall even more rapidly at age 42 and beyond.

Many doctors recommend that women over 35 have a fertility evaluation after attempting pregnancy for six months. Couples under age 35 should consider evaluation if conception does not occur after trying for a year. A woman using donor insemination should ask her physician about an infertility evaluation after six months.

Other conditions that can interfere with a woman’s ability to conceive and carry a child to term include:

Infertility in Men

A couple’s failure to achieve conception is equally as likely to result from a problem with the man as with the woman.

Male infertility can be divided into problems with:

  • Ejaculation and erection
  • The fine, small reproductive tract ducts
  • Sperm production

Problems with sperm production is by far the most common of the three and can be detected during semen analysis. There are many causes of abnormal sperm production, including:

  • Varicocele (varicose veins)
  • Genetic problems
  • Infections
  • Exposures to heat or toxic chemicals
  • Drugs and medications
  • Hormonal imbalance

Over the last several decades, concern has risen about the impact of industrialization on reproductive health. This concern stems largely from reports showing that semen quality of men in Europe and North America has decreased over the latter half of the 20th century. The environmental toxins most often cited as potential contributors to infertility can be organized into physical, chemical, occupational and lifestyle factors.

  • Physical factors include hyperthermia (increased temperature), radiation and electromagnetic fields
  • Chemical causes include cigarette smoking, excessive alcohol consumption, marijuana and cocaine use as well as caffeine intake
  • Occupational hazards include some pesticides, industrial toxins like dioxin and polychlorinated biphenyls (PCBs), and exposure to heavy metals
  • Stress, nutrition and other lifestyle factors also can play a role

Any fertility treatment may be expected to have an effect on semen quality roughly three months after it is started, as this is the length of time required for a single cycle of spermatogenesis, or sperm production. If neither surgical nor medical therapy is appropriate, assisted reproductive technologies are possible.

Spina Bifida

Spina bifida (SB) is a neural tube defect (a disorder involving incomplete development of the brain, spinal cord, and/or their protective coverings) caused by the failure of the fetus’s spine to close properly during the first month of pregnancy.

Infants born with SB sometimes have an open lesion on their spine where significant damage to the nerves and spinal cord has occurred. Although the spinal opening can be surgically repaired shortly after birth, the nerve damage is permanent, resulting in varying degrees of paralysis of the lower limbs. Even when there is no lesion present there may be improperly formed or missing vertebrae and accompanying nerve damage.

The three most common types of SB are:

  • Myelomeningocele – the severest form, in which the spinal cord and its protective covering (the meninges) protrude from an opening in the spine
  • Meningocele – in which the spinal cord develops normally but the meninges protrude from a spinal opening
  • Occulta – the mildest form, in which one or more vertebrae are malformed and covered by a layer of skin.

SB may also cause bowel and bladder complications, and many children with SB have hydrocephalus (excessive accumulation of cerebrospinal fluid in the brain). In addition to physical and mobility difficulties, most individuals have some form of learning disability.

The prognosis for individuals with SB depends on the number and severity of abnormalities. Prognosis is poorest for those with complete paralysis, hydrocephalus, and other congenital defects. With proper care, most children with SB live well into adulthood.

There is no cure for SB because the nerve tissue cannot be replaced or repaired. Treatment for the variety of effects of SB may include surgery, medication, and physiotherapy. Many individuals with SB will need assistive devices such as braces, crutches, or wheelchairs. Ongoing therapy, medical care, and/or surgical treatments may be necessary to prevent and manage complications throughout the individual’s life. Surgery to close the newborn’s spinal opening is generally performed within 24 hours after birth to minimize the risk of infection and to preserve existing function in the spinal cord.

Hydranencephaly

Hydranencephaly is a rare condition in which the brain’s cerebral hemispheres are absent and replaced by sacs filled with cerebrospinal fluid.

It may be caused by vascular infections or traumatic disorders after the 12th week of pregnancy.

Hydranencephaly is considered to be an extreme form of porencephaly, a rare disorder characterized by a cyst or cavity in the cerebral hemispheres.

An infant with hydranencephaly may appear normal at birth. The infant’s head size and spontaneous reflexes such as sucking, swallowing, crying, and moving the arms and legs may all seem normal. However, after a few weeks the infant usually becomes irritable and has increased muscle tone. After a few months of life, seizures and hydrocephalus (excessive accumulation of cerebrospinal fluid in the brain) may develop. Other symptoms may include:

  • Visual impairment
  • Lack of growth
  • Deafness
  • Blindness
  • Spastic quadriparesis (paralysis)
  • Intellectual deficits

Some infants may have additional abnormalities at birth including seizures, myoclonus (spasm or twitching of a muscle or group of muscles), and respiratory problems.

Diagnosis may be delayed for several months because early behavior appears to be relatively normal.

The outlook for children with hydranencephaly is generally poor, and many children with this disorder die before age 1. However, in rare cases, children with hydranencephaly may survive for several years or more.

There is no definitive treatment for hydranencephaly. Treatment is symptomatic and supportive. Hydrocephalus may be treated with a shunt (a surgically implanted tube that diverts fluid from one pathway to another).

Holoprosencephaly

Holoprosencephaly is a disorder caused by the failure of the prosencephalon (the embryonic forebrain) to sufficiently divide into the double lobes of the cerebral hemispheres. The result is a single-lobed brain structure and severe skull and facial defects. Normally, the forebrain is formed and the face begins to develop in the fifth and sixth weeks of pregnancy.

The exact cause of holoprosencephaly are yet to be determined, although the presence of toxins may be suspected. However, it often seems that there is no specific cause at all.

There are three classifications of holoprosencephaly:

  • Alobar – in which the brain has not divided at all, is usually associated with severe facial deformities
  • Semilobar – in which the brain’s hemispheres have somewhat divided, causes an intermediate form of the disorder
  • Lobar – in which there is considerable evidence of separate brain hemispheres, is the least severe form. In some cases of lobar holoprosencephaly the baby’s brain may be nearly normal

In most cases of holoprosencephaly, the malformations are so severe that babies die before birth. In less severe cases, babies are born with normal or near-normal brain development and facial deformities that may affect the eyes, nose, and upper lip.

The least severe of the facial anomalies is the median cleft lip (premaxillary agenesis). The most severe is cyclopia, an abnormality characterized by a single eye located in the area normally occupied by the root of the nose, and a missing nose or a proboscis (a tubular-shaped nose) located above the eye. The least common facial anomaly is ethmocephaly, in which a proboscis separates closely-set eyes. Cebocephaly, another facial anomaly, is characterized by a small, flattened nose with a single nostril situated below incomplete or underdeveloped closely-set eyes.

Moderate to severe defects may cause:

  • Mental retardation
  • Spastic quadriparesis
  • Athetoid movements
  • Endocrine disorders
  • Epilepsy
  • Other serious conditions

Mild brain defects may only cause learning or behavior problems with few motor impairments.

Seizures may develop over time with the highest risk before 2 yrs of age and the onset of puberty. Most are managed with one medication or a combination of medications. Typically, seizures that are difficult to control appear soon after birth, requiring more aggressive medication combinations and doses.

Most children with holoprosencephaly are at risk of having elevated blood sodium levels during moderate-severe illnesses, that alter fluid intake/output, even if they have no previous diagnosis of diabetes insipidus or hypernatremia.

The prognosis for individuals with the disorder depends on the severity of the brain and facial deformities.

There is no standard course of treatment for holoprosencephaly. Treatment is symptomatic and supportive.

Anencephaly

Anencephaly is a defect in the closure of the neural tube during fetal development. The neural tube is a narrow channel that folds and closes between the 3rd and 4th weeks of pregnancy to form the brain and spinal cord of the embryo.

The cause of anencephaly is unknown. Although it is thought that a mother’s diet and vitamin intake may play a role, scientists believe that many other factors are also involved.

Anencephaly occurs when the “cephalic” or head end of the neural tube fails to close, resulting in the absence of a major portion of the brain, skull, and scalp. Infants with this disorder are born without a forebrain (the front part of the brain) and a cerebrum (the thinking and coordinating part of the brain). The remaining brain tissue is often exposed–not covered by bone or skin.

A baby born with anencephaly is usually blind, deaf, unconscious, and unable to feel pain. Although some individuals with anencephaly may be born with a rudimentary brain stem, the lack of a functioning cerebrum permanently rules out the possibility of ever gaining consciousness. Reflex actions such as breathing and responses to sound or touch may occur.

The prognosis for babies born with anencephaly is extremely poor. If the infant is not stillborn, then he or she will usually die within a few hours or days after birth.

There is no cure or standard treatment for anencephaly. Treatment is supportive.

Recent studies have shown that the addition of folic acid (vitamin B9) to the diet of women of childbearing age may significantly reduce the incidence of neural tube defects. Therefore it is recommended that all women of childbearing age consume 0.4 mg of folic acid daily.

Prolactinoma

A prolactinoma is a benign (noncancerous) tumor of the pituitary gland that produces a hormone called prolactin. Prolactinomas are the most common type of pituitary tumor.

Prolactin stimulates the breast to produce milk during pregnancy. After giving birth, a mother’s prolactin levels fall unless she breastfeeds her infant. Each time the baby nurses, prolactin levels rise to maintain milk production.

Although small benign pituitary tumors are fairly common in the general population, symptomatic prolactinomas are uncommon. Prolactinomas occur more often in women than men and rarely occur in children.

The cause of pituitary tumors remains largely unknown. Most pituitary tumors are sporadic, meaning they are not genetically passed from parents to their children.

Symptoms of prolactinoma are caused by too much prolactin in the blood (hyperprolactinemia) or by pressure of the tumor on surrounding tissues. In women, high levels of prolactin in the blood often cause infertility and changes in menstruation. In some women, periods may stop. In others, periods may become irregular or menstrual flow may change. Women who are not pregnant or nursing may begin producing breast milk. Some women may experience a loss of interest in sex. Intercourse may become painful because of vaginal dryness.

In men, the most common symptom of prolactinoma is erectile dysfunction. Because men have no reliable indicator such as changes in menstruation to signal a problem, many men delay going to the doctor until they have headaches or eye problems caused by the enlarged pituitary pressing against nearby optic nerves. They may not recognize a gradual loss of sexual function or libido. Only after treatment do some men realize they had a problem with sexual function.

The goals of treatment are to:

  • Return prolactin secretion to normal
  • Reduce tumor size
  • Correct any visual abnormalities
  • Restore normal pituitary function

In the case of large tumors, only partial achievement of these goals may be possible.

Because dopamine is the chemical that normally inhibits prolactin secretion, doctors may treat prolactinoma with the dopamine agonists bromocriptine (Parlodel) or cabergoline (Dostinex). Agonists are drugs that act like a naturally occurring substance. These drugs shrink the tumor and return prolactin levels to normal in approximately 80 percent of patients.

Surgery to remove all or part of the tumor should only be considered if medical therapy cannot be tolerated or if it fails to reduce prolactin levels, restore normal reproduction and pituitary function, and reduce tumor size. If medical therapy is only partially successful, it should be continued, possibly combined with surgery or radiation.

Rarely, radiation therapy is used if medical therapy and surgery fail to reduce prolactin levels.

How does prolactinoma affect pregnancy?

If a woman has a small prolactinoma, she can usually conceive and have a normal pregnancy after effective medical therapy. If she had a successful pregnancy before, the chance of her having more successful pregnancies is high.

A woman with prolactinoma should discuss her plans to conceive with her physician so she can be carefully evaluated prior to becoming pregnant. This evaluation will include an MRI scan to assess the size of the tumor and an eye examination with measurement of visual fields.

As soon as a woman is pregnant, her doctor will usually advise her to stop taking the medications. Although the drugs are safe for the fetus in early pregnancy, their safety throughout an entire pregnancy has not been established. Many doctors prefer to use bromocriptine in patients who plan to become pregnant because it has a longer record of safety in early pregnancy than cabergoline.

The pituitary enlarges and prolactin production increases during pregnancy in women without pituitary disorders. Women with prolactin-secreting tumors may experience further pituitary enlargement and must be closely monitored during pregnancy. Less than 3 percent of pregnant women with small prolactinomas have symptoms of tumor growth such as headaches or vision problems. In women with large prolactinomas, the risk of symptomatic tumor growth is greater, and may be as high as 30 percent.

Most endocrinologists see patients every 2 months throughout the pregnancy. A woman should consult her endocrinologist promptly if she develops symptoms of tumor growth—particularly:

  • Headaches
  • Vision changes
  • Nausea
  • Vomiting
  • Excessive thirst or urination
  • Extreme lethargy

Treatment with medications may be reinitiated and additional treatment may be required if the woman develops symptoms during pregnancy.

Diabetes Insipidus

Diabetes insipidus (DI) is a rare disease that occurs when the body’s precise system of regulating the kidneys’ handling of fluids is disrupted, causing frequent urination.

The body has a complex system for balancing the volume and composition of body fluids. The kidneys remove extra body fluids from the bloodstream. These fluids are stored in the bladder as urine. If the fluid regulation system is working properly, the kidneys make less urine to conserve fluid when water intake is decreased or water is lost, for example, through sweating or diarrhea.

With DI, the large volume of urine is diluted, mostly water. To make up for lost water, a person with DI may feel the need to drink large amounts and is likely to urinate frequently, even at night, which can disrupt sleep and, on occasion, cause bedwetting. Because of the excretion of abnormally large volumes of dilute urine, people with DI may quickly become dehydrated if they do not drink enough water. Children with DI may be irritable or listless and may have fever, vomiting, or diarrhea.

Diabetes insipidus should not be confused with diabetes mellitus (DM), which results from insulin deficiency or resistance leading to high blood glucose, also called blood sugar. DI and DM are unrelated, although they can have similar signs and symptoms, like excessive thirst and excessive urination. DI is a different form of illness altogether.

Milder forms of DI can be managed by drinking enough water, usually between 2 and 2.5 liters a day. DI severe enough to endanger a person’s health is rare.

Central DI results from damage to the pituitary gland, which disrupts the normal storage and release of ADH – antidiuretic hormone that directs the kidneys to reabsorb water into the bloodstream and make less urine. Damage to the pituitary gland can be caused by different diseases as well as by head injuries, neurosurgery, or genetic disorders.

To treat the ADH deficiency that results from any kind of damage to the hypothalamus or pituitary, a synthetic hormone called desmopressin can be taken by an injection, a nasal spray, or a pill.

Nephrogenic DI results when the kidneys are unable to respond to ADH. The kidneys’ ability to respond to ADH can be impaired by drugs and by chronic disorders including polycystic kidney diseasesickle cell disease, kidney failure, partial blockage of the ureters, and inherited genetic disorders. Sometimes the cause of nephrogenic DI is never discovered.

A person with nephrogenic DI may be given hydrochlorothiazide (HCTZ) or indomethacin. HCTZ is sometimes combined with another drug called amiloride. The combination of HCTZ and amiloride is sold under the brand name Moduretic.

Dipsogenic DI is caused by a defect in or damage to the thirst mechanism, which is located in the hypothalamus. This defect results in an abnormal increase in thirst and fluid intake that suppresses ADH secretion and increases urine output.

Scientists have not yet found an effective treatment for dipsogenic DI.

Gestational DI occurs only during pregnancy and results when an enzyme made by the placenta destroys ADH in the mother.

Most cases of gestational DI can be treated with desmopressin. In rare cases, however, an abnormality in the thirst mechanism causes gestational DI, and desmopressin should not be used.