Things That Can Harm a Fetus

Creatas Images/Creatas/Getty Images

During pregnancy, the health and safety of the foetus depends significantly on external factors. Anything that the mother is exposed to or consumes can affect the foetus, potentially causing birth defects or even a miscarriage. Avoiding known risks to the foetus can help the pregnancy go as smoothly as possible. Always check with your doctor to learn about any risks or things that can harm your foetus that are specific to your pregnancy.

Environmental Factors

Many toxins and other environmental factors can pose serious risks to the foetus. Exposure to radiation and lead contributes to serious birth defects in the foetus. Avoid lead-based paint and getting X-rays if pregnant. Heavy metals and acids can also poison the foetus. Even common household cleaners can pose a risk to the foetus; check all cleaning product labels for any risks to pregnant women.


Both cat faeces and raw meat can carry parasites responsible for causing toxoplasmosis, a serious disease that causes brain damage or blindness in the foetus. This disease is generally harmless to adults, but the foetus is more vulnerable. Avoid eating raw meat and cleaning up after cats when pregnant. Exposure to the parasite also occurs while gardening if the cat lives primarily outdoors.

Alcohol and Tobacco

Alcohol poses severe risks to the foetus, causing mental and physical defects. Since alcohol can pass through the placenta, any amount can harm the foetus. Consumption of alcohol during pregnancy can lead to fetal alcohol syndrome, causing slow progress in mental and physical development and facial deformities. Smoking also causes problems for the foetus, such as a low birth weight or premature birth. Premature birth and low birth weight mean that the foetus does not develop properly, and this can lead to other issues after birth.


Any disease that the mother has at the start of the pregnancy, or contracts while pregnant, can put the foetus at risk. Hepatitis, AIDS and some other STDs can be transmitted directly to the foetus and require treatment after the baby is born. Other diseases such as diabetes, lupus, anaemia, hypertension and rubella can also cause pregnancy complications or birth defects.


Both over-the-counter and prescription medications can potentially put the foetus at risk. Over-the-counter drugs such as ibuprofen and aspirin can hinder the blood's ability to clot, putting both mother and foetus at risk. They can also affect hormone levels. Prescription drugs used to treat conditions such as acne, psoriasis, migraines, epileptic seizures and heart disease can sometimes cause birth defects or pregnancy complications, so check with your doctor about any prescription medications you need to take.

Illegal drugs can also harm the foetus if the mother abuses them while pregnant. When exposed to street drugs such as cocaine and heroin, the foetus can be born addicted to those drugs, causing a traumatic withdrawal process for the baby. Illegal drugs can also cause birth defects and miscarriage or stillbirth.


Exposure to sources of high levels of heat in the first trimester of pregnancy, such as hot tubs, saunas or baths, can sometimes cause birth defects. Internal sources of heat, such as a high fever, can cause the same problem. However, if you have a fever, make sure that the fever-reducing medication you take is safe for pregnant women.


Listeria is a bacteria that sometimes occurs in uncooked food products, such as meat, dairy products, and vegetables. This bacteria causes an infection called listeriosis, which has the potential to cause miscarriage or infections and death to the newborn as well as making the pregnant mother quite ill. As pregnant women are more susceptible to this infection, they should always make sure that food is cooked properly in order to kill the bacteria. Listeriosis can be contracted by consuming not only raw or undercooked foods, but by eating foods such as cold deli meat and soft cheeses, as well.


Caffeine has the potential to cause miscarriages and birth defects if consumed in large quantities. A moderate amount of caffeine is safe to consume, but since that amount has not been conclusively determined, you should generally try to consume as little as possible. Caffeine is a stimulant and can cross through the placenta to the foetus, so any caffeine consumed directly affects the foetus. The stimulating effect of caffeine can rates both the mother and the foetus' heart rate, putting the foetus at risk. In high doses, caffeine can even cause preterm labour.

Most recent