How Does Listeria Affect The Unborn Baby?

Listeria is a bacterial foodborne infection. Infection is caused by eating contaminated food with Listeria monocytogenes. Usually this bacterium is present in uncooked meats, uncooked vegetables, unpasteurized milk and processed food. Listeria infection is rare, but there is a high incidence of death associated with the infection.

If a pregnant woman gets infected with L. monocytogenes she will be most probably asymptomatic.

If listeria becomes symptomatic infections presents as flu-like illness with fever, body pains, and headache, backache often preceded by diarrhea or other gastrointestinal symptoms.

The infection can be transmitted to the baby via the placenta and this can cause serious problems in the baby while still in the womb or shortly after birth.

Problems That Can Occur In The Fetus And Newborn Baby Because Of Listeria Are:

Miscarriage: If the listeria infection occurs early in the pregnancy (during the first 3 months), it may end up in a miscarriage. Sometimes you might not even know that you were pregnant.

Infection of the Placenta and/or Amniotic Fluid: The placenta provides the required oxygen and nutrition to the fetus from the mother. The baby lies in a sealed sac surrounded with fluid. This fluid is amniotic fluid. It protects the baby from trauma acting as a cushion in the womb. Also it facilitates the exchange of nutrient, water and other metabolic products between mother and the fetus.

Listeria can infect the placenta or the amniotic fluid. Then the fetus will not receive oxygen and nutrients that is needed for the growth and development. Also the fetus can get the infection as well.

Preterm Birth: Preterm birth is birth before 37 weeks of gestation. Listeria infection of the placenta, amniotic fluid or fetus can result in preterm birth. Babies born before 37 weeks (term) will have respiratory problems, intestinal problems, feeding difficulties, temperature control difficulties, metabolic problems and heart problems. This can even lead to death of the newborn baby.

• Granuloamatosis Infantosepticum: Granuloamatosis infantosepticum is an intrauterine infection with high fetal or neonatal mortality (death). The infection is generalized in the fetus and characterized by extensive erythematous rash with pale nodules or granulomas in the liver, spleen, skin, adrenal glands, lungs and brain.
• Neonatal Infections: Baby can develop symptomsfew days after birth orfew weeks after birth from an exposure while inside the womb or while passing through the birth canal. The infection in the newborn can be fatal. The infection can be:

  1. Early onset 

     Symptoms and signs are seen within few hours after birth. These babies are low birth weight with other obstetric complications. Usually the respiratory and circulatory insufficiency with pneumonia is seen in these babies. Aspiration or swallowing of amniotic fluid or the vaginal secretions can lead in utero or afterbirth infection of the lungs. Symptoms and signs are:

     • Breathing difficulties
     • Fever
     • Grunting – abnormal noise made when breathing
     • Tachypnea (increase respiratory rate)
     • Nasal flaring
     • Intercostal and subcostal recessions – when breathing the chest depressions are prominent

  2. Late Onset 

     Symptoms and signs are delayed up to several weeks. Most of time this is due to the infection presenting with features of neonatal sepsis or meningitis. Symptoms and signs are:

     • Fever
     • Poor feeding
     • Lethargy
     • Drowsiness
     • Fits (convulsions)

Stillbirths/Neonatal Death: 22% of cases of perinatal listeriosis result in stillbirth or neonatal death.

When a pregnant woman becomes infected with Listeria monocytogenes she will be asymptomatic most of the time, if not non-specific flu-symptoms can occur. Listeria infection can be transmitted to the baby in utero or while passing through the birth canal and this can be fatal to the fetus/ newborn baby. Listeriosis can cause miscarriages, preterm birth, infection of the placenta and/or amniotic fluid, fetal/neonatal infection (neonatal sepsis, neonatal meningitis), and stillbirths or neonatal death. As you see the complications are quite severe prevention of listeria infection in a pregnant woman is important.

References:

Also Read:

• What is Listeriosis or Listeria, Know its Causes, Symptoms, Treatment, Prevention, Prognosis
• Can Listeria be Transmitted from Person to Person?
• How do you Know If you have Listeria?
• What are the First Signs of Listeria?
• Where to Look for Listeria and How to Avoid it?