Friday, July 12, 2013

Illnesses Affecting The Introduction Of An Infant

Most women who become pregnant will have no complications and will give birth to healthy babies. In the past it was believed that the baby was completely protected while growing in the uterus. We had thought that the fetus was completely protected from any outside influences. Today, we know that this is not the case and that environmental influences can affect the development of the fetus. These influences include not only those bombarding the mother from the outside world but also toxins found in the mother's own bloodstream. Such toxins can include chemicals, hormones, viruses and other microscopic organisms which affect the prenatal development of the infant.


All of these toxins and other environmental influences affect the health of the baby because as a fetus grows and develops from a zygote to an embryo and beyond, the different organs and structures of the body grow at different rates.


The first three months of pregnancy are particularly critical months in the development of the embryo. This is the period of time in which the tissues and body systems begin to develop. Any adverse environmental toxins encountered during this period usually affect the very basic structure and form of the fetus's body, especially the nervous system. Malformation may occur and physical development may slow down or stop.


Although the placental barrier is effective against filtering out some dangerous environmental influences, it cannot filter out extremely small microorganisms, such as viruses and bacteria. Infants, whose mothers develop or have active disease, can then be born with measles, mumps, chickenpox, syphilis and many other diseases as a result.


When infection is spread from the mother to the baby it is defined as vertical transmission. Infections can occur during three separate periods of growth and development. When the fetus is still growing in the uterus it is known as an in utero or congenital infection. Newborns may also become infected during labor and delivery and finally, the infant may become infected in the neonatal period or the period of a month after the infant was born.


The infections that we will discuss are those infectious processes that are congenital in nature; that is those that affect the baby in utero. A number of infectious microorganisms cause congenital infection. Congenital infection can lead to problems in fetal development and even death.


An acronym for the most common congenital infections is TORCH. These infections are toxoplasmosis; other infections (syphilis, hepatitis B, Coxsackievirus, varicella zoster virus and human parvovirus); Rubella; Cytomegalovirus (CMV); and Herpes Simplex Virus.


Your obstetrician will decide what tests you may require based on an assessment of your medical history and risk factors, as well as exposure to any infectious diseases. She will base care on results from ultrasounds and evaluations during your prenatal visits. Your health care provider will decide whether or not you will nee


Toxoplasmosis


Toxoplasmosis is a protozoal infection that can cause severe congenital malformations when maternal infection occurs during pregnancy. The effects of toxoplasmosis occur primarily during the fetal stage of development rather than during organ development in the embryonic stage.


Effects on the fetus include prematurity, central nervous system defects, mental retardation, low birth weight, enlarged spleen, destructive changes in the eye or in the brain. Toxoplasmosis can also lead to death of the fetus.


Maternal signs and symptoms of toxoplasmosis are vague if they are present at all as the disease is usually asymptomatic. Consult with a physician who specializes in viral diseases if you have had a history of handling cat feces or of eating raw meat. Toxoplasmosis is contracted through eating infected raw meat or meat that is undercooked and through contact with infected cat feces from cleaning out a litter box.


Other Diseases


The consequences of contracting sexually transmitted diseases during pregnancy can result in long-term effects on the health of your baby. Sexually transmitted diseases are one of the leading complications during pregnancy, affecting approximately two million pregnant women.


Although in the past, approximately 33 percent of infants infected with syphilis were stillborn, the incidence of fetal death has decreased. The microorganism responsible for syphilis infection is called a spirochete and it easily crosses the placenta resulting in infection of the fetus. The highest incidence of congenital infection occurs in neonates whose mothers have early syphilis. Once the woman has entered late latent disease, disease that is greater than one-year duration, the incidence is at its lowest. However, fetal infection may occur in any stage of maternal syphilis.


Consequences as a result of fetal or neonatal infection can include: blindness, deafness, facial deformity and neurological problems. Skin lesions, pneumonia, myocarditis (an inflammation of the heart muscles) and abnormal kidneys are other conditions associated with congenital syphilis. Congenital syphilis is also responsible for a degenerative bone condition, especially in the femur, tibia or radius. The infant receives poor nutrition and blood supply as the placenta becomes large and pale with diminishing capacity to nourish the fetus.


Hepatitis is an inflammation of the liver that can be caused by several different viruses. Hepatitis B is one of the most common forms in the United States. Transmission of hepatitis B to the fetus is also quite common when there is maternal infection.


Hepatitis B is transmitted through blood, blood products, contaminated needles, saliva, vaginal secretions and semen. In fact, it is found in all bodily fluids except for breast milk, according to "Varney's Midwifery". Vertical transmission of hepatitis B to the fetus has serious consequences for the newborn. Infection can result in a chronic state increasing the risk for chronic active hepatitis, chronic liver disease, cirrhosis of the liver and liver cancer later in life.


Women who test positive for the antigens, which indicate active or early hepatitis B disease, have a 90 percent chance of passing the disease to their infants. Ninety percent of infected infants will become carriers and 25 percent will die of cirrhosis or primary liver cancer.


Coxsackie infections, though usually asymptomatic in the pregnant woman, can cause aseptic meningitis, rashes, respiratory disease or heart problems. Because the disease can be fatal to the fetus and newborn, it is considered a serious complication of pregnancy. Infection from the Coxsackievirus can cause injuries to the embryo and fetus producing congenital anomalies and malformations. Other conditions that exposure to Coxsackievirus may cause include hepatitis, myocarditis and encephalomyelitis (an inflammation of the brain and spinal cord) which can cause fetal death.


Varicella, or chickenpox, is an extremely contagious viral infection caused by a form of herpes virus. Varicella during pregnancy can have serious consequences for both the mother and the fetus or infant. The earlier in pregnancy that a woman develops varicella, the greater the risk of congenital varicella syndrome. The greatest risk occurs in the first 20 weeks of pregnancy. According to "Varney's Midwifery",


congenital varicella syndrome is associated with cataracts, chorioretinitis (inflammatory condition of the retina of the eye), limb hypoplasia (incomplete or underdeveloped organs or tissues), bony leg defects, hydronephrosis, microcephaly (a congenital anomaly characterized by abnormal smallness of the head in relation to the rest of the body), mental retardation, or problems involving skin or dermal layer development.


Maternal varicella infection occurring from six days before through two days after delivery can also be passed on to the newborn as there is insufficient time for maternal immunity to develop and be passed on to the baby. Varicella vaccine is an attenuated live vaccine and is, therefore, contraindicated in pregnancy.


The Human B19 parvovirus causes a skin infection called fifth disease, which appears clinically as a bright red rash which gives the face the appearance of having been slapped. The rash is accompanied by joint pain. It is thought to be an immune complex disease. Although in some women, the disease is asymptomatic, maternal infection can be associated with adverse pregnancy outcomes, including abortion and fetal death. Parvovirus has been linked to congenital anomalies in the fetus, as a result of first trimester infection. Evidence for fetal myocardial damage has been found as well.


Rubella


The virus that causes rubella, or German measles, is particularly pathogenic during pregnancy. It is the most widespread of the viruses causing abnormalities in the fetus. Mothers who contract rubella during the first trimester, or the first three months of pregnancy, have an approximately 40 percent chance that their baby will be born with congenital malformations. The most common malformations include cataracts, cardiac defects and deafness. Other abnormalities may exhibit as glaucoma, microcephaly, and other defects involving the eyes, ears, heart, brain and central nervous system. The most severely affected fetuses may abort spontaneously.


There is no direct relationship between the severity of the disease in the mother and its effect on the fetus. For example, women having mild attacks of rubella have been known to give birth to babies with severe congenital rubella syndrome. Women who have not been immunized against rubella and contract the disease during the first trimester of pregnancy are often given a very tough decision by their health care providers as to whether to obtain a therapeutic abortion. There are no chemical agents to prevent the disease once it has been contracted. Vaccination during pregnancy is not recommended because the vaccine is a live virus, although no evidence of adverse effects from the vaccine have been demonstrated.


Cytomegalovirus (CMV)


Cytomegalovirus is a form of herpes virus that eventually infects just about every one during their lifetime. The most common cause is perinatal infection. Cytomegalovirus is another of the microorganisms with the potential to cause severe congenital malformations when contracted during pregnancy. CMV exerts its effect during the fetal period, after the first trimester, rather than during the embryonic period.


Maternal infection is usually asymptomatic with the disease unsuspected until birth. Congenital cytomegalovirus infection, termed cytomegalic inclusion disease has a plethora of symptoms including low birth weight, microcephaly, calcifications in the brain, chorioretinitis, mental and motor retardation, sensorineural defects, liver disease, and blood diseases. Infants born with the disease are predisposed to seizures, blindness, encephalitis and learning disabilities. There is no vaccine and no effective treatment for the infection.


Fortunately, of the estimated 40,000 babies born infected in the United States every year, only approximately 10 percent demonstrate cytomegalic inclusion disease, which is more prevalent in neonates born to women whose primary infection occurred during the first half of her pregnancy.


Herpes Simplex Virus (HSV)


The fetus almost always becomes infected with herpes simplex virus during viral shedding from the cervix or the lower genital tract. The virus may also invade the uterus after the membranes have been ruptured or the fetus will come in contact with the virus during delivery. Newborn infection can take one of three forms: disseminated disease with involvement of the major organs; localized infection, where involvement is confined to the central nervous system, eyes, skin or mucosa; or asymptomatic. As many as 50 percent of infected newborns are born prematurely. Risk of infection to the newborn directly correlates with whether maternal infection is primary or recurrent.


Localized infection is usually associated with better outcomes. Conversely, even with treatment of the disease with various medications known to be effective in the suppression of HSV, disseminated neonatal infection is associated with a 60 percent mortality rate. Serious ophthalmic and central nervous system damage has been identified in at least half of the survivors.


Considerations


Although the pregnant woman and her fetus are susceptible to a number of infections and infectious diseases, some of which can be quite serious and life-threatening for the mother as well as having a profound impact on neonatal outcome, preconceptual care may help to avoid many adverse conditions. Take part in your care and educate yourself about infectious diseases which can affect the growth and development of your newborn. Be sure to notify your health care provider about exposure to any of the above or other infectious disease processes. Again, the majority of women will have an uncomplicated pregnancy with a healthy infant, but this is not the time to take chances with your or your infant's health.









Related posts



    How the Smoke Reaches the FetusSmoking cigarettes during pregnancy more damage to the fetus than to the mother. When the smoke from a cigarette enters the body, some of the additives are quickly e...
    Nicotine is a toxic chemical in cigarette smoke that can be absorbed into the blood through the lungs and passed from a mother to her unborn baby. The effects of nicotine on unborn babies can be c...
    How Does Cigarette Smoke Affect a Fetus?InstructionsCigarette Smoke Exposes a Fetus to Toxic Substances1. When a pregnant woman smokes, she risks miscarriage and negatively affects her unborn chil...
    How Does Smoking Affect a Fetus?How Does Smoking Affect a Fetus?Smoking during pregnancy is never a good idea, as it can severely affect the unborn child. The nicotine in cigarettes can cause arte...
    Periodontal DiseaseIt is estimated that over half the cases of periodontal disease can be attributed to tobacco use. Periodontal disease and gum disease are the same condition. It is a bacterial i...