How does alcohol affect pregnancy?
Alcohol has been implicated in infertility, early miscarriage, as well as in birth defects. The amount of alcohol consumption necessary to cause these problems is not known, and varies among women. Some women can drink excessively and have normal infants. Others consume considerably less alcohol but still give birth to babies with cognitive disabilities and/or other birth defects. It is generally believed that the greater the amount of alcohol consumed during pregnancy, the greater the risk of pregnancy-related problems and birth defects.It is recommended that pregnant women avoid all consumption of alcohol. Fetal alcohol spectrum disorders are a group of conditions reflecting the possible effects of prenatal exposure to alcohol. The FASDs include fetal alcohol syndrome (FAS), alcohol-related birth defects (ARBD), and alcohol-related neurodevelopmental disabilities (ARND). Fetal alcohol syndrome (FAS) is the extreme end of the fetal alcohol spectrum disorders and is a leading cause of cognitive disabilities.
How do high blood pressure and diabetes affect pregnancy?
Elevated blood pressure (hypertension) that is present before pregnancy can interfere with growth of the fetus and increase the risk of fetal death. Therefore, controlling blood pressure with carefully chosen blood pressure medications is important during pregnancy and before conception.In addition, underlying hypertension can increase the risk for a condition called preeclampsia, a potentially very dangerous complication of pregnancy. It is sometimes difficult for doctors to distinguish between high blood pressure alone and high blood pressure occurring from preeclampsia. For those reasons, and given the risk of birth defects from many of the blood pressure medications, women with high blood pressure who become pregnant should be followed very carefully by a medical expert who is familiar with this type of situation. Ideally, medication would be switched to a relatively safe medication before the woman even becomes pregnant.
Poorly controlled diabetes can lead to high blood sugar levels. High blood sugar levels during early pregnancy can lead to miscarriages and birth defects. Therefore, controlling diabetes is important for a good pregnancy outcome, and the blood sugar should ideally be controlled before becoming pregnant. It is important to consider that control of blood sugar during pregnancy is important, but control prior to pregnancy may be just as important.
Oral diabetes medications may be dangerous to the fetus, but insulin is not dangerous to the fetus. Insulin is the key treatment for diabetes during pregnancy. Not only is insulin safe to the baby and mother, but it also helps prevent the complications that the baby could have suffered from the mother's sugar being uncontrolled. Insulin is usually substituted for pills as soon as a woman with diabetes is considering pregnancy. The ideal time to control blood sugar is before pregnancy, because control of sugar levels even in early pregnancy (when the mother does not yet know she is pregnant) is important for the developing baby's health.
What are examples of commonly-used medications that are dangerous in pregnancy?
Many women do not know that over-the-counter medications can be dangerous. In fact, many prescription and over-the-counter medications harm the fetus very early in pregnancy at a time that the mother does not even know she is pregnant. Even aspirin use by the mother can cause defects in the fetus. For this reason, as soon as pregnancy is being contemplated, women should avoid all over-the-counter and prescription medications until reviewed with their doctor.Acne medications, such as isotretinoin (Accutane) can cause birth defects, and should be discontinued before conception. Since many medications and substances can affect fetal growth and development, pregnancy planning is important so that potentially harmful substances can be stopped before conceiving.
Unplanned pregnancy during oral contraceptive use is not felt to pose a significant danger to the fetus, although deliberate use of oral contraceptives during pregnancy is not advisable. Women who become pregnant during oral contraceptive use have the same risk of birth defects in their newborns as the general population of women, in the range of 2% to 3%.
How do kidney and heart disease affect pregnancy?
Because pregnancy is associated with an increase in blood volume and an increase in cardiac output as well as other changes in the circulatory system, many types of heart disease may worsen or be associated with poor outcome during pregnancy. While many mild chronic heart conditions may be well tolerated during pregnancy, other conditions pose a significant risk to mother and fetus. Women with preexisting heart disease should always consult an expert when planning a pregnancy to examine their own degree of risk, potential outcomes, and treatment options.What infections affect pregnancy?
Certain infections during early pregnancy can cause birth defects in the fetus. Rubella (German measles) virus infection during early pregnancy can cause birth defects and even miscarriages. Therefore, women of child bearing age are tested for blood antibodies against this virus. Women lacking rubella virus antibodies are susceptible to rubella infection, and should be vaccinated against this virus. Pregnancy should be avoided for one month after vaccination, due to the theoretical concern that the vaccine virus itself may cause fetal damage.Toxoplasmosis is a small parasite that is transmitted through cat feces and raw meats, especially pork. Toxoplasmosis, like the rubella virus, can cause severe birth defects if the infection occurs during early pregnancy. Women planning pregnancy should avoid raw meat and avoid handling the cat litter box. Many people have been exposed to toxoplasmosis without even knowing it. As a result, they develop a protective immunity from the "silent" infection. Women who have a blood test that is positive for toxoplasmosis immunity can be reassured that they will not develop toxoplasmosis complications during pregnancy.
Hepatitis B is the only type of hepatitis that is known to affect the newborn infant.
Female healthcare workers, dental assistants, and others exposed to hepatitis B should receive hepatitis B vaccination to avoid chronic infection by this virus. The majority of hepatitis B virus infections resolve spontaneously without treatment. Patients whose disease resolves completely are no longer contagious. Approximately 10% of hepatitis B virus infections do not resolve, and become chronic. Patients chronically infected with hepatitis B virus may have no symptoms of liver disease early on, but they remain contagious. Over time, chronic hepatitis B infection can lead to liver cirrhosis and/or liver cancer.
Women with chronic hepatitis B infection can transmit the virus to their babies at birth. Babies infected are at risk of developing chronic liver disease, liver cirrhosis, and liver cancer in later life. Currently, infants born to mothers infected with the hepatitis B virus are given both the hepatitis B antibodies and hepatitis B vaccinations at birth for protection. Therefore, pregnant women are often tested for signs of hepatitis B infection, even if they do not have any symptoms or knowledge of past infection. The babies of infected mothers detected in this manner would receive special care at (and after) delivery.
Cytomegalovirus (CMV) is a common viral infection worldwide that often does not produce any symptoms. Women who become infected or have a reactivation of a previous infection during pregnancy may pass the infection along to their babies. Congenital CMV infection is the most common congenital viral infection. Although the majority of infected infants will not have any symptoms, up to 20% will have symptoms that may include an enlarged spleen, jaundice, or rash. Rarely, involvement of many organs may occur resulting in severe illness or disability.
Genital herpes may also result in the passage of the infection to the infant at the time of delivery. The risk of transmission is increased if the genital lesions are from a herpesvirus (HSV) infection acquired during the pregnancy, rather than simply a reactivation of previous disease. HSV infection can have multiple effects in the newborn. Disease may be limited to the eyes, skin and mouth; may be localized to the central nervous system; or may be widespread and involve many organs. Treatment involves administration of antiviral medications to the newborn and supportive care.
Parvovirus B19 is a virus that causes the condition known as Fifth disease, a common mild disease of childhood. Transmission is by droplets in the air (respiratory secretions) or through blood. Pregnant women who have not previously had fifth disease should avoid contact with those who have it because parvovirus B-19 can infect a fetus prior to birth. Although no birth defects have been reported as a result of fifth disease, it can cause the death of an unborn fetus. This occurs in less than 5% of pregnant women who become infected with the virus.
When traveling to a foreign country, it is important to determine what diseases are common, whether vaccines are needed, and whether they are safe during pregnancy. Human immunodeficiency virus (HIV) infection can be passed from a mother to her baby. The chances of this happening are decreased substantially with certain medication programs during pregnancy. Pregnant women are routinely offered testing for HIV infection. Women with previously undetected infection who are found to have HIV infection can be given special medication to try to protect the baby. At the same time, the medication may benefit the health of the mother herself.
Varicella, or chickenpox, can cause pneumonia or even death in older adults and in pregnant women. Varicella vaccine is available for women who are not immune to chickenpox. Women who had chickenpox in the past do not need a vaccine because they are immune. Women who are not sure if they are immune can receive a blood test to determine immunity status. A vaccine would be given if the blood test showed they were not immune.
Is it safe to exercise during pregnancy?
Recommendations from the American College of Obstetrics and Gynecology say that pregnant women who have an uncomplicated pregnancy should participate in at least 30 minutes of moderate exercise on most, if not all, days of the week. A few exceptions are noted: ice hockey, kickboxing, soccer, and horseback riding probably should be avoided because they are activities with higher risk of trauma to the abdomen. Also, scuba diving poses a risk of decompression sickness ("the bends") to the fetus and should be avoided. Exercise programs should be discussed with the monitoring health care professional.Elevated temperatures can have adverse effects on the development of the fetus. Therefore, hot tubs and sauna baths should be avoided when trying to conceive and during pregnancy.
