Listeria causes miscarriage because the bacteria can cross the placenta, leading to infection and severe inflammation in the uterus and placenta, disrupting fetal development or causing the body to expel the pregnancy to protect the mother, resulting in preterm birth, stillbirth, or miscarriage, even if the mother has mild or no symptoms. The bacteria's ability to invade cells and spread directly to the fetus makes pregnancy a high-risk time due to hormonal changes weakening immune defenses, explains.
The estimated incidence of pregnancy related Listeriosis is 3–4 cases per 100,000 births. Maternal infection within the first trimester of pregnancy has an associated risk of miscarriage estimated at 65%, while infection in the 2nd or 3rd trimester has an associated risk of fetal demise estimated at 26%.
Listeriosis can lead to miscarriage, premature labor, the delivery of a low-birth-weight infant, or infant death. Late-term fetuses who have an infection may develop a wide range of health problems, including intellectual disability, paralysis, seizures, blindness, or impairments of the brain, heart, or kidney.
Infection may cause stillbirth through various mechanisms, including severe maternal illness, direct fetal infection, and placental injury.
Every year in the United States, about 1 in 25,000 pregnant women are infected with Listeria. Listeria can spread to your baby during pregnancy cause harm, even if you do not feel very sick. Sadly, 1 in 4 pregnant women who get this illness lose their pregnancy or their baby shortly after birth.
Gonorrhea, bacterial vaginosis, brucellosis, and listeriosis have been shown to consistently increase the chance of miscarriage. Another bacterial infection that has clear associations with miscarriage, although seemingly of lesser strength, is salmonella infection.
Some foods are more likely to be tainted by the bacteria than others. These include soft cheeses, deli meats and dairy products that haven't been treated to kill bacteria, called pasteurized. Healthy people rarely become very ill from listeria infection.
Chromosome conditions
If your baby inherits a chromosome condition, they'll not be able to develop properly. This causes a miscarriage. It's not possible to tell which parent passed on the chromosome condition. Chromosome conditions are thought to be the most common cause of an early miscarriage.
Listeriosis during pregnancy can also increase the chance for serious health problems after birth. Newborn babies infected with Listeria can develop either early-onset or late-onset listeriosis. Early onset listeriosis develops 1-2 days after birth, and the baby often has signs of a serious bacterial infection.
Also on the list of foods to avoid during pregnancy? Unwashed vegetables, such as lettuce, salads and raw sprouts. According to the FDA, these pose a higher risk of food illness for pregnant people, as they can harbor bacteria such as salmonella, listeria and E. coli.
With these two animal models, researchers were able to identify that two Listeria proteins, called InlA and InlB, interact with specific receptors, respectively E-cadherin and Met, which allow them to adhere to the placenta and cross it to reach the fetus.
Listeria may not infect many people each year, but it's important to be aware of it. Pregnant women (and their unborn babies), older adults and people with weakened immune systems are at higher risk of becoming ill and likely to experience severe symptoms.
Invasive illness
"Invasive" means bacteria have spread beyond the intestines (gut). Invasive listeriosis happens when Listeria spreads beyond the intestines. Symptoms of invasive illness usually start within 2 weeks after eating food contaminated with Listeria.
The good news is that you can choose safer food options to protect your baby during your pregnancy. Listeria can grow at cold temperatures in refrigerators, but it is easily killed by heat. In general, foods that are safer include: Cooked or reheated foods that reach a high enough temperature for germs to be killed.
No testing, including blood and stool cultures, or treatment is indicated for an asymptomatic pregnant woman who reports consumption of a product that was recalled or implicated during an outbreak of listeria contamination.
If you get listeriosis while you're pregnant, there is a risk it could cause miscarriage or stillbirth. In babies and people with a weakened immune system, listeriosis can sometimes lead to serious and life-threatening problems such as sepsis or meningitis.
You may also have a stiff neck, headache, confusion, or loss of balance. Symptoms may appear as late as 2 months after you have eaten something with Listeria. Even if you do not feel very sick, you can pass the infection to your fetus.
Specific deli meats to avoid during pregnancy include hot dogs, lunch meats, cold cuts, and other deli meats. Heating these meats to an internal temperature of 165°F or until steaming hot can help eliminate the risk of listeria infection for pregnant women.
Your chance of miscarriage is highest when you first find out you're pregnant — around week 3 or 4. During weeks 3 and 4 of pregnancy, the miscarriage rate is roughly 25% to 33% of all pregnancies. After week 4, the rate drops to 15% to 20% between weeks 5 and 6.
Even though you lost your child during pregnancy or soon after, you are still a parent. Take care of yourself.
There is no evidence of reduction in the risk of miscarriage in women prescribed bed rest. HCG administration as an alternative care for threatened miscarriage was more effective than bed rest in the Harrison study but this benefit is not confirmed when compared with placebo.
Listeriosis is a form of food poisoning you get from the bacteria Listeria monocytogenes. Many people refer to this bacterial infection as just “Listeria.” For many people, a Listeria infection causes mild symptoms like a fever, headache, diarrhea or vomiting.
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Listeria infection is rare. An estimated 1,600 people in the U.S. get sick from Listeria each year. Some foods are more likely than others to be contaminated with Listeria.