In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to lice or scabies may increase the risk for birth defects over that background risk. This information should not take the place of medical care and advice from your health care provider.

What are lice?

Lice are parasitic insects that can live on the body or in hair. Head lice are the most common type of lice. Lice hatch out of eggs that are called nits. Nits are usually yellow or white and are about the size of a knot in thread. Adult lice have six legs and are a tan to grayish-white color. Adult lice are about the size of a sesame seed. Lice usually cause itching and rashes. You can get lice by touching someone who has lice, mainly from head to head contact. It may also be possible to get lice from sharing an infected person’s clothing, towels, brushes, or other personal items. Lice crawl; they cannot jump or fly. Lice cannot live more than 2-4 days off the human body. Head lice are not known to spread disease.

What is scabies?

Scabies is the spread of mites (a type of insect) on the skin. The mites are so small they usually cannot be seen with the naked eye. The mites burrow into the skin and cause itching and rashes. You can get scabies by touching someone who has scabies, but usually you have to be touching for a long time (more than just a quick handshake). You can also get scabies by sharing clothes, towels, or bedding with someone who has scabies.

How can I tell if I have lice or scabies?

Lice will cause itching and rashes, usually on the scalp. You can sometimes see adult lice crawling through hair or on the scalp. You can also look for the nits (eggs) attached to the hair close to the scalp.

Scabies will cause itching all over the body and it is usually most severe at night. You may see a rash or raised S-shaped lines on the skin. Your health care provider can tell if you have scabies by taking a scraping of the skin and looking for the mites or their eggs under a microscope.

How can I protect myself from getting lice or scabies during my pregnancy?

If someone in your household or other close contact has lice or scabies, it is possible for you to get them too. To prevent this from happening, the person that has lice or scabies needs to be treated as soon as possible. All clothing and bed linens that the person wore or came in contact with in the two days before treatment should be dry-cleaned or washed in HOT water and dried in high heat for at least 20 minutes, and/or removed from body contact for at least 72 hours. The person’s combs and brushes should be soaked in rubbing alcohol or a disinfectant for one hour. If they are heat resistant, they can be soaked in hot water (at least 130 degrees) for 5-10 minutes. Floors, furniture, car seats and other fabric covered items should be vacuumed.

I am pregnant and I have lice. What over-the-counter products can I use to get rid of the lice?

Over-the-counter lice medications are usually cream rinses for hair. Typically, they contain either permethrin (brand name Nix®) or pyrethrin and piperonyl butoxide (one brand name Rid®). There are different brands available at the drugstore, and new medicines are coming onto the market. MotherToBaby does not make specific recommendations for treatment; talk with your health care provider for specific recommendations. There are also other treatments available by prescription.

Permethrin, pyrethrin and piperonyl butoxide are insecticides that do not pass through the skin into the blood in high amounts. Most animal studies have not shown an increased chance for birth defects when these insecticides were used during pregnancy. Small studies of women who used permethrin during pregnancy did not show an increase in the chance for birth defects. The Centers for Disease Control and Prevention (CDC) recommends that women use permethrin or pyrethrin/piperonyl butoxide to treat lice during pregnancy. Always follow the instructions on the bottle carefully. If a 2nd treatment is recommended, be sure to follow the timeline instructions. Reapplying too soon or too late can lower treatment success.

What if the lice do not go away after using over-the-counter products?

If over-the-counter treatments fail to kill the lice, you should see a health care provider about getting a different kind of lice medication. Common prescription medications for lice are malathion and ivermectin. There are no human studies looking at women who have been treated with malathion during pregnancy, but most animal studies have not shown an increased chance for birth defects. Ivermectin is not well studied in pregnancy, and therefore should not be used while pregnant according to the CDC.

What do I do if I think I have scabies during my pregnancy?

If you think you have scabies, you should see a health care provider. They will look at your skin carefully. To confirm a diagnosis of scabies, your healthcare provider may take a scraping of your skin. Your health care provider may prescribe a stronger kind of permethrin cream than what is available over-the-counter. One study has shown no increased chance of adverse effects in pregnancy outcome after using permethrin or another treatment, benzyl benzonate lotion. Another treatment that is thought not to increase risk when used in pregnancy is sulfur in petrolatum. However, some health care providers have questioned how well it works to treat scabies. Lindane is also sometimes used to treat scabies if other treatments fail. Lindane can cause toxic side effects in children and adults and is generally avoided in pregnancy. Studies in pregnant animals have not shown lindane to cause birth defects. You should talk to your health care provider about the benefits and risks of using your specific prescription medication to treat scabies during pregnancy, or contact MotherToBaby with the name of your medication so that we can discuss your specific exposure.

What lice and scabies medications can I use while I’m breastfeeding?

Because absorption after topical use is limited, the CDC suggests that breastfeeding women use pyrethrin or permethrin to treat lice and scabies. Ivermectin passes into breast milk in small amounts. Lindane is usually avoided during breastfeeding because it is not recommended for use in young children. Malathion is not well studied in breastfeeding mothers. If you are breastfeeding, talk to a health care provider before using a prescription medication to treat lice or scabies. Be sure to talk to your health care provider about all of your breastfeeding questions.

What if the father of the baby uses lice or scabies medication?

There have been no human studies looking at paternal exposures to lice and scabies medications. However, most medications are not thought to increase the chance of birth defects when a father uses them before or around the time of conception. Lice and scabies may be spread through sexual intercourse. As mentioned, any household member that has lice or scabies should be treated immediately to prevent spreading to other household members.

For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/.

References Available By Request