Medical Conditions and Pregnancy

Medical conditions that may affect pregnancy

Certain medical conditions may complicate a pregnancy. However, with proper medical care, most women can enjoy a healthy pregnancy, despite their medical challenges.

Diabetes before pregnancy

Diabetes is a condition where sufficient amounts of insulin are either not produced or the body is unable to use the insulin that is produced. Insulin is the hormone that allows glucose to enter the cells of the body to provide fuel. When glucose cannot enter the cells, it builds up in the blood and the body's cells literally starve to death. Diabetes in pregnancy can have serious consequences for the mother and the growing fetus. The severity of problems often depends on the severity of the mother's diabetic disease, especially if she has vascular (blood vessel) complications and poor blood glucose control.

Diabetes that occurs in pregnancy is described as:

• Gestational diabetes--when a mother who does not have diabetes develops a resistance to insulin because of the hormones of pregnancy. Women with gestational diabetes may be noninsulin dependent or insulin dependent.

• Pregestational diabetes--women who already have diabetes and become pregnant.

What is gestational diabetes?

Gestational diabetes is a condition in which the glucose level is elevated and other diabetic symptoms appear during pregnancy in a woman who has not previously been diagnosed with diabetes. In most cases, all diabetic symptoms disappear following delivery. However, women with gestational diabetes have an increased risk of developing diabetes later in life, especially if they were overweight before pregnancy.

Unlike other types diabetes, gestational diabetes is not caused by a lack of insulin, but by blocking effects of other hormones on the insulin that is produced, a condition referred to as insulin resistance.

What causes gestational diabetes?

Although the cause of gestational diabetes is not known, there are some theories as to why the condition occurs.

The placenta supplies a growing fetus with nutrients and water, as well as produces a variety of hormones to maintain the pregnancy. Some of these hormones (estrogen, cortisol, and human placental lactogen) can have a blocking effect on insulin, which usually begins about 20 to 24 weeks into the pregnancy.

As the placenta grows, more of these hormones are produced, and insulin resistance becomes greater. Normally, the pancreas is able to make additional insulin to overcome insulin resistance, but when the production of insulin is not enough to overcome the effect of the placental hormones, gestational diabetes results.

What are the risk factors associated with gestational diabetes?

Although any woman may develop gestational diabetes during pregnancy, some of the factors that may increase risk are:

• Family history of diabetes

• Obesity

• Having given birth previously to a very large infant, a stillbirth, or a child with a birth defect

• Age (women who are older than 25 are at greater risk than younger women)

Although increased glucose in the urine is often included in the list of risk factors, it is not believed to be a reliable indicator for gestational diabetes.

How is gestational diabetes diagnosed?

A glucose screening test is usually performed between 24 and 28 weeks of pregnancy, which involves drinking a special glucose drink followed by measurement of the blood sugar level after one hour.

If this test shows an increased blood sugar level, a three-hour glucose tolerance test may be performed after a few days of following a special diet. If results of the second test are in the abnormal range, gestational diabetes is diagnosed.

Treatment for gestational diabetes

Specific treatment for gestational diabetes will be determined by your physician or midwife based on:

• Your age, overall health, and medical history

• Severity of the disease

• Your tolerance for specific medications, procedures, or therapies

• Expectations for the course of the disease

• Your opinion or preference

Treatment for gestational diabetes focuses on keeping blood glucose levels in the normal range. Treatment may include:

• Special diet

• Exercise

• Daily blood glucose monitoring

• Insulin injections

Possible gestational diabetes complications for the baby

Unlike other types of diabetes, gestational diabetes generally does not cause birth defects. Birth defects usually originate sometime during the first trimester of pregnancy. They are more likely in women with pregestational diabetes, who may have changes in blood glucose during that time. Women with gestational diabetes generally have normal blood sugar levels during the critical first trimester.

The complications of gestational diabetes are usually manageable and preventable. The key to prevention is careful control of blood sugar levels just as soon as the diagnosis of gestational diabetes is made.

Infants of mothers with gestational diabetes are vulnerable to several chemical imbalances, such as low serum calcium and low serum magnesium levels, but, in general, the major problems of gestational diabetes include the following:

• Macrosomia
  Macrosomia refers to a baby that is considerably larger than normal. All of the nutrients the fetus receives come directly from the mother's blood. If the maternal blood has too much glucose, the pancreas of the fetus senses the high glucose levels and produces more insulin in an attempt to use this glucose. The fetus converts the extra glucose to fat. Even when the mother has gestational diabetes, the fetus is able to produce all the insulin it needs. The combination of high blood glucose levels from the mother and high insulin levels in the fetus results in large deposits of fat which causes the fetus to grow excessively large.

• Birth injury
  Birth injury may occur due to the baby's large size and difficulty being born.

• Hypoglycemia
  Hypoglycemia refers to low blood sugar in the baby immediately after delivery. This problem occurs if the mother's blood sugar levels have been consistently high, causing the fetus to have a high level of insulin in its circulation. After delivery, the baby continues to have a high insulin level, but it no longer has the high level of sugar from its mother, resulting in the newborn's blood sugar level becoming very low. The baby's blood sugar level is checked after birth, and if the level is too low, it may be necessary to give the baby glucose intravenously.

• Respiratory distress (difficulty breathing)
  Too much insulin or too much glucose in a baby's system may delay lung maturation and cause respiratory difficulties in babies. This is more likely if they are born before 37 weeks of pregnancy.

High blood pressure and pregnancy

High blood pressure can occur in pregnancy in two forms. It may be a preexisting condition, called chronic hypertension, or it can develop during pregnancy--a condition known as gestational hypertension. It is also called toxemia or preeclampsia and occurs most often in young women with a first pregnancy. It is more common in twin pregnancies, and in women who had blood pressure problems in a previous pregnancy.

High blood pressure can lead to placental complications and slowed fetal growth. If untreated, severe hypertension may cause dangerous seizures and even death in the mother and fetus.

Women with preeclampsia may need bedrest. Moderate or severe preeclampsia or eclampsia usually require hospitalization and medications.

Women who have high blood pressure before pregnancy often need to continue taking their antihypertensive medication. Your physician may switch you to a safer antihypertensive medication during pregnancy.

Kidney function tests and ultrasounds are often performed more frequently on pregnant women with high blood pressure to monitor the mother's health and fetal growth and development.

Infectious diseases and pregnancy

Infections during pregnancy can pose a threat to the fetus. Even a simple urinary tract infection, which is common during pregnancy, should be treated immediately. An infection that goes untreated can lead to preterm labor and rupture of the membranes surrounding the fetus. Some infectious diseases include:

• Toxoplasmosis
  Toxoplasmosis is an infection caused by a single-celled parasite named Toxoplasma gondii. Although many people may have toxoplasma infection, very few have symptoms because the immune system usually keeps the parasite from causing illness. Babies who became infected before birth can be born with serious mental or physical problems. Toxoplasmosis often causes flu-like symptoms, swollen lymph glands, or muscle aches and pains that last for a few days to several weeks. Mothers can be tested to see if they have developed an antibody to the illness. Fetal testing may include ultrasound, and/or testing of amniotic fluid or cord blood. Treatment may include antibiotics. The Centers for Disease Control and Prevention (CDC) recommends the following measures to help prevent toxoplasmosis infection:

  • Wear gloves when you garden or do anything outdoors that involves handling soil. Cats, who may pass the parasite in their feces, often use gardens and sandboxes as litter boxes. Wash your hands well with soap and warm water after outdoor activities, especially before you eat or prepare any food.

  • Have someone who is healthy and not pregnant change your cat's litter box. If this is not possible, wear gloves and clean the litter box daily (the parasite found in cat feces can only infect you a few days after being passed). Wash your hands well with soap and warm water afterward.

  • Have someone who is healthy and not pregnant handle raw meat for you. If this is not possible, wear clean, latex gloves when you touch raw meat and wash any cutting boards, sinks, knives, and other utensils that might have touched the raw meat. Wash your hands well with soap and warm water afterward.

  • Cook all meat thoroughly, that is, until it is no longer pink in the center or until the juices run clear. Do not sample meat before it is fully cooked.

• Food poisoning
  A pregnant woman should avoid eating undercooked or raw foods because of the risk of food poisoning. Food poisoning can dehydrate a mother and deprive the fetus of nourishment. In addition, food poisoning can cause meningitis and pneumonia in a fetus, resulting in possible death. Tips for preventing food poisoning include:

  • Thoroughly cook raw food from animal sources, such as beef, pork, or poultry.

  • Wash raw vegetables thoroughly before eating.

  • Keep uncooked meats separate from vegetables and from cooked foods and ready-to-eat foods.

  • Avoid raw (unpasteurized) milk or foods made from raw milk.

  • Wash hands, knives, and cutting boards after handling uncooked foods.