Pregnancy Planning (cont.)

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.