Diabetes before pregnancy:

A person with diabetes produces little or no insulin, 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.

Uncontrolled diabetes before pregnancy can lead to birth defects, miscarriage, and stillbirth. If blood sugar levels are under control in a woman with diabetes, many complications can be avoided. Many women with diabetes have healthy pregnancies.

Babies born to mothers with poorly controlled diabetes (preexisting or gestational) are at higher risk for jaundice, breathing problems, and low blood sugar levels.

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.

Unlike type 1 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 and 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 risks factors associated with gestational diabetes?

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

• obesity
• family history of diabetes
• having given birth previously to a very large infant, a still birth, or a child with a birth defect
• having too much amniotic fluid
• women who are older than 25 are at greater risk than younger women

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

How is gestational diabetes diagnosed?

Gestational diabetes is diagnosed with a glucose screening test, which, generally, involves drinking a glucose drink followed by measurement of glucose levels after a one-hour interval.

If this test shows a blood sugar level of greater than 140 mg/dl, another test will be performed after a few days of following a special diet. The second test also involves drinking a glucose drink, and results are measured at three-hour intervals.

If results of the second test are in the abnormal range, gestational diabetes is diagnosed.

Treatment for gestational diabetes:

Specific treatment will be determined by your physician or certified nurse practitioner based on:

• your age, overall health, and medical history
• extent 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 (rarely)

Possible complications for the baby:

Unlike type 1 diabetes, gestational diabetes generally does not cause birth defects. Birth defects usually originate sometime during the first trimester (before the 13th week) of pregnancy. But, the insulin resistance from the contra-insulin hormones produced by the placenta does not usually occur until approximately the 24th week. 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 but, in general, there are two major problems of gestational diabetes:

• 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 cause the fetus to grow excessively large.

• 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.

High blood pressure and pregnancy:

High blood pressure can either be a preexisting condition or develop during pregnancy. Extremely high blood pressure can lead to placental complications and slowed fetal growth. Severely high blood pressure can also endanger a woman’s life during pregnancy.

Women with slightly high blood pressure may be ordered by a physician to discontinue the hypertensive medication.

However, women with moderately high blood pressure 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 usually performed regularly on pregnant women with moderately 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 premature labor and rupture of the membranes surrounding the fetus. Some common infectious diseases include:

• toxoplasmosis

  To prevent infection, pregnant women should avoid all contact and exposure to cat feces and cat litter, which may contain a parasite toxoplasma gondii that causes toxoplasmosis. Other sources of infection include insects (i.e., flies) that have been in contact with cat feces and should be avoided during pregnancy. Toxoplasmosis can cause a serious illness in, or death, of the fetus. A pregnant woman can reduce her risk of infection by avoiding all potential sources of the infection. A blood test before or during pregnancy can determine if a woman has been exposed to the toxoplasma gondii parasite.

• 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.

• sexually transmitted diseases

  Infections such as chlamydia can lead to premature labor and rupture of the membranes. A woman with human immunodeficiency virus (HIV) has a one-in-four chance of infecting her fetus. Genital herpes can be spread to the baby during delivery, if a woman has an active infection at that time.