An infection caused by a bacteria or virus that can be passed from a mother to her baby during pregnancy or delivery is called a perinatal infection.
Perinatal infections include bacterial or viral illnesses that can be passed from a mother to her baby either while the baby is still in the uterus or during the delivery process. Maternal infection can, in some cases, cause complications at birth. The mother may or may not experience active symptoms of the infection during the pregnancy. Some perinatal infections are sexually transmitted.
Transmission of many perinatal infections occurs during childbirth, particularly in cases when invasive techniques such as episiotomy or artificial rupture of membranes are employed. In other cases, transmission may occur during pregnancy, if the infectious agent can cross the placental barrier, and it may occur during breastfeeding, if the infectious agent can be found in breast milk.
The incidence of perinatal infection depends on the causative agent of infection. For example, perinatal transmission of cytomegalovirus occurs in two to 24 out of every 1,000 live births. The rate of transmission of genital herpes during pregnancy is one to two out of every 2,000 pregnancies; the rate of transmission during childbirth changes to one out of every 2,000 to 5,000 live births. Perinatal transmission of group beta streptococcus causes neonatal infection in one to five out of every 1,000 live births, and rubella (German measles), 0.02 out of every 1,000 live births. HIV is transmitted from untreated mother to child in 25 to 40 percent of cases, but in only 1 percent of cases if mother receives treatment and the infant receives prophylaxis.
The following represent some of the more common infections that can be transmitted perinatally.
The bacterium Chlamydia trachomatis is the cause of the most common bacterial sexually transmitted disease in the United States, causing more than 4 million infections each year. The majority of women with chlamydial infection experience no obvious symptoms. The infection affects the reproductive tract and causes pelvic inflammatory disease, infertility, and ectopic pregnancy (when the fertilized egg implants somewhere other than in the uterus). This infection can cause premature rupture of the membranes and early labor. It can be passed to the infant during delivery and can cause ophthalmia neonatorum (an eye infection) within the first month of life and pneumonia within one to three months of age. Symptoms of chlamydial pneumonia are a repetitive cough and rapid breathing. Wheezing is rare and the infant is usually without a fever.
Cytomegalovirus (CMV) is a common virus in the herpes virus family. It is found in saliva, urine, and other body fluids and can be spread through sexual contact or other more casual forms of physical contact such as kissing. In adults, CMV may cause mild symptoms of swollen lymph glands, fever, and fatigue. Many people who carry the virus experience no symptoms at all. Infants can become infected with CMV while still in the uterus if the mother becomes infected or develops a recurrence of the infection during pregnancy. Although most infants exposed to CMV before birth develop normally and do not show any symptoms, as many as 6,000 infants who were exposed to CMV before birth are born with serious complications each year. CMV interferes with normal fetal development and can cause mental retardation, blindness, deafness, or epilepsy in these infants.
Genital herpes, which is usually caused by herpes simplex virus type 2 (HSV-2), is a sexually transmitted disease that causes painful sores on the genitals. Women who have their first outbreak of genital herpes during pregnancy are at high risk of miscarriage or delivering a low birth weight baby. The infection can be passed to the infant at the time of delivery if the mother has an active sore. The most serious risk to the infant is the possibility of developing HSV-2 encephalitis, an inflammation of the brain, with symptoms of irritability and poor feeding.
Hepatitis B is a contagious virus that causes liver damage and is a leading cause of chronic liver disease and cirrhosis. Approximately 20,000 infants are born each year to mothers who test positive for the hepatitis B virus. These infants are at high risk for developing hepatitis B infection through exposure to their mothers blood during delivery.
Human immunodeficiency virus (HIV) is a serious, contagious virus that causes acquired immunodeficiency syndrome (AIDS). About 25 to 40 percent of untreated pregnant women pass the infection on to their newborn infants, while only 1 percent of treated pregnant women transmit the virus. There are often no symptoms of HIV in infants, but within a few months most infants who are infected show signs of opportunistic infections such as failure to thrive, chronic thrush, and persistent diarrhea.
Human papillomavirus (HPV) is a sexually transmitted disease that causes genital warts and can increase the risk of developing some cancers. HPV appears to be transferred from the mother to the infant during the birth process and can cause tracheal narrowing due to lesions (warts) from the virus.
Rubella is a virus that causes German measles, an illness that includes rash, fever, and symptoms of an upper respiratory tract infection. Most people are exposed to rubella during childhood and develop antibodies to the virus so they never get it again. Rubella infection during early pregnancy can pass through the placenta to the developing infant and cause serious birth defects, including heart abnormalities, mental retardation, blindness, and deafness.
Group beta streptococcus (GBS) infection is the most common bacterial cause of infection and death in newborn infants. Although rates have declined in the United States since the introduction of antibiotics to at-risk women during labor in the 1980s, about 1,600 cases and 80 newborn deaths still occur each year. In women, GBS can cause vaginitis and urinary tract infections. Both infections can cause premature birth, and the bacteria can be transferred to the infant in the uterus or during delivery. GBS causes pneumonia, meningitis, and other serious infections in infants.
Syphilis is a sexually transmitted bacterial infection that can be transferred from a mother to an infant through the placenta before birth. Up to 50 percent of infants born to mothers with syphilis are premature or stillborn or die shortly after birth. Infected infants may have severe birth defects. Those infants who survive infancy may develop symptoms of syphilis up to two years later.
Pregnant women who exhibit symptoms of infection should contact their healthcare provider to determine if the infection can be passed vertically to the child during pregnancy, childbirth, and/or breastfeeding. In some cases, early detection and treatment of infection can minimize the risk of perinatal transmission.
How a bacterial or viral infection is diagnosed depends on the causative agent. Examples include the following:
Methods of treating some of the more common causes of perinatal infection include:
The prognosis of a neonate who has contracted an infection perinatally depends on the specific infection. Examples include the following:
Use of a barrier method of contraceptive (e.g. condom) can prevent transmission of some sexually transmitted infections during intercourse. Intravenous drug use and sexual intercourse with infected partners increase the risks of exposure to most of these infections. Pregnant women can be tested for many of the bacterial or viral infections described; however, effective treatment may not be available to protect the infant.
In some cases, the method of childbirth may impact the chance of passing an infection from mother to child. For instance, research has shown that delivering a baby by caesarian section over vaginal delivery reduces the risk of transmitting HIV from mother to child.
A woman's nutritional status may contribute to her ability to fight off infections, particularly in cases of malnutrition. A well-balanced diet rich in nutrients such as folic acid, calcium, iron, zinc, vitamin D, and the B vitamins is recommended for pregnant women. Mothers are recommended to eat approximately 300 additional calories day (above and beyond a normal nonpregnancy diet) to support the fetus's growth and development.
Cesarean section—Delivery of a baby through an incision in the mother's abdomen instead of through the vagina; also called a c-section, cesarean birth, or cesarean delivery.
Ectopic pregnancy—A pregnancy that develops outside of the mother's uterus, such as in the fallopian tube. Ectopic pregnancies often cause severe pain in the lower abdomen and are potentially life-threatening because of the massive blood loss that may occur as the developing embryo/fetus ruptures and damages the tissues in which it has implanted.
Encephalitis—Inflammation of the brain, usually caused by a virus. The inflammation may interfere with normal brain function and may cause seizures, sleepiness, confusion, personality changes, weakness in one or more parts of the body, and even coma.
Episiotomy—An incision made in the perineum (the area between the vulva and the anus) during labor to assist in delivery and to avoid abnormal tearing of the perineum.
Perinatal—Referring to the period of time surrounding an infant's birth, from the last two months of pregnancy through the first 28 days of life.
Pneumonia—An infection in which the lungs become inflamed. It can be caused by nearly any class of organism known to cause human infections, including bacteria, viruses, fungi, and parasites.
Minimizing the risk of transmitting a maternal infection to a fetus is often a major concern for parents. The first step is identifying possible maternal infections. Proper prenatal care in many cases allows for early diagnosis and thus early treatment of certain infections, thus improving the newborn's prognosis.
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March of Dimes Birth Defects Foundation. 1275 Mamaroneck Ave., White Plains, NY 10605. Web site: http://.
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Altha Roberts Edgren Teresa G. Odle Stephanie Dionne Sherk
The following comments are not guaranteed to be that of a trained medical professional. Please consult your physician for advice.