Pinworm infection, also called enterobiasis or oxyuriasis, is a common worm infestation in humans. Pregnancy does not pose a risk for pinworm infection, but coming in contact with eggs of pinworms from infected people, objects, or surfaces may lead to worm infestation during pregnancy (1).
Read this MomJunction post to know more about the causes, signs and symptoms, diagnosis, treatment, and prevention of pinworm infection during pregnancy and the safety of deworming drugs.
What Are Pinworms?
A pinworm is a tiny, white roundworm (nematode) that grows inside the gastrointestinal tract of humans during its entire lifecycle. It is a common intestinal parasite.
Pinworms are also known as seatworms, enterobius vermicularis, or threadworms. They cause helminthiasis (worm infection) in humans.
Pinworms grow in the bowel and infect the anal area. They are highly contagious parasites that may infect all members of a family if one of them is infected (2).
What Are The Causes Of Pinworm Infections During Pregnancy?
Lack of proper hygiene is the leading cause of pinworm infections in pregnant women. The following may make you more susceptible to pinworm infection:(3):
- Not washing the hands properly before eating and after using the toilet
- Not washing the hands before cooking
- Not trimming and cleaning the fingernails
- Not cleaning the household items, bed sheets, towels, etc.
- Living in crowded living conditions
- Sharing clothes
How Are Pinworms Spread In Pregnancy?
Pinworms can be spread from an infected person to another by direct touch or through objects. Eggs of pinworms can spread to another person from surfaces where the infected person has touched after scratching the affected area.
It may also spread from clothes and bedsheets. Pinworms usually survive for two to three weeks.
In rare cases, pinworm infection can be caused by the inhalation of airborne pinworm eggs.
After reaching the intestines, these eggs start to hatch. A new worm can start laying eggs within two weeks. This may cause reinfection in a person if they do not follow good hygiene practices (4).
Signs And Symptoms Of Pinworm Infection During Pregnancy
Some may not develop any symptoms of infection. The usual symptoms and signs of pinworm infection in pregnant women can be (3):
- Anal itching, more intense in night hours
- Vaginal itching
- Abdominal pain or cramps
- Weight loss
- Loss of appetite
- Sleep disturbances
It is recommended that you consult your doctor if you have any of these symptoms. Though it may not affect your baby, it may affect your well-being.
Complications Of Pinworm Infection During Pregnancy
Generally, pinworm infections do not cause serious complications. In rare cases, heavy infestations can cause infection of the female genitals. Heavy infestation of pinworm happens if you leave it untreated and do not follow good personal hygiene. It may also cause weight loss in some women.
In certain cases, it may result in the movement of the parasite from the anal area to the vagina or urethra and cause the following (5):
- Vaginitis (inflammation of the vagina)
- Endometritis (inflammation of the inner lining of the uterus)
- Salpingitis (inflammation of the fallopian tubes)
- Urinary tract infection
- Appendicitis in long-standing worm infestation
- Superficial bacterial infection due to the scratching of the anal area
Diagnosis Of Pinworm Infection During Pregnancy
Pinworm infection can be diagnosed using (6):
- Tape test: It is a diagnostic test done using transparent adhesive tapes. Place adhesive tape around the anal area as soon as you wake up in the morning for three consecutive days. This makes the eggs stick to the tape. Your doctor can then confirm the presence of worms by observing the tape under a microscope.
- Moistened swab: A wet swab can be used to collect and identify pinworm eggs in the anal area.
- Fingernail samples: Sometimes, the worms can be diagnosed by analyzing the samples from under the fingernails using a microscope.
Pinworm Treatment During Pregnancy
- Mebendazole: The drug that kills the worms by blocking the uptake of nutrients and glucose from the intestine.
- Albendazole (Albenza): It reduces energy production in worms, thus causing death and immobilization of the parasite.
- Pyrantel pamoate (Pin-X, Reese’s pinworm medicine): It blocks the nerves in worms and leads to paralysis of the parasite, thus facilitating the removal of the worm in the stool.
Dosage: Anthelmintic medications are given in a single dose initially, followed by another dose of the same drug after two weeks to avoid the possible risk of reinfection (7).
Your doctor may prescribe prescription anthelmintic such as mebendazole or albendazole. Otherwise, they may recommend over-the-counter pyrantel pamoate to you and others in the family to prevent pinworm infection.
Note: It is recommended that you follow good hygiene practices to avoid reinfection. Even though the worms die with medications, their eggs may survive up to two to three weeks and cause reinfections.
Safety Of Deworming Drugs During Pregnancy
All the three drugs mentioned above belong to the category C drugs for pregnancy. Category C drugs are the drugs that have shown some adverse effects in animal experiments, but there are not enough studies about their effects on humans. Despite the risks, these drugs are usually recommended if there is a plausible benefit (9).
Deworming during pregnancy is usually recommended if the pinworm infection affects the wellbeing of a pregnant woman, often due to weight loss or sleep disturbances.
Mebendazole is not contraindicated during breastfeeding. And there are not enough studies on the safety of the other drugs during breastfeeding (9).
Note: It is recommended that you consult your doctor if you or a family member has pinworm infection when you are pregnant. Do not take over-the-counter deworming medications before consulting your doctor. Your doctor will recommend the appropriate treatment or hygiene measures based on the requirement.
How To Prevent Pinworm Infection When Pregnant
The following hygiene practices may help in the prevention of pinworm infection and reinfection during pregnancy (10):
- Wash your hands with soap after using the washroom and before meals.
- Avoid putting your fingers in the mouth.
- Take regular showers.
- Wash the anal area in the morning to reduce the eggs.
- Change your underwear daily.
- Change your bed covers daily.
- Wash your clothes in warm water with detergent and dry them on high heat.
- Keep your fingernails trimmed.
- Avoid scratching the anal area.
- Do not share towels and clothes.
- Keep your house clean.
Although some anecdotal home remedies for pinworm infections, such as the application of coconut oil, tea tree oil, apple cider vinegar, or crushed garlic, may be practiced by some people, there is no scientific evidence that they could reduce worm infestation and reinfection.
Home treatments, such as the consumption of carrots and probiotics to improve digestive health, may have certain positive effects. However, there are not enough studies to say that these could be used as alternatives to anthelmintic treatments.
The risk of pinworm infection can be high among households with young children. Anthelmintic medications and proper hygiene practices can help you avoid pinworm infections. Failure to follow hygiene measures and leaving the infection untreated can result in an infestation of worms in the vagina or bladder.
2. Parasites- Enterobiasis (also known as pinworm infection); The Centers for Disease Control and Prevention
3. Pinworm infection; New York State Department of Health
4. Pinworm infection FAQs; The Centers for Disease Control and Prevention
5. Prashanth Rawla and Sandeep Sharma; Enterobius Vermicularis (Pinworm); The United States National Library of Medicine
6. Diagnosis; Parasites- Enterobiasis (also known as pinworm infection); The Centers for Disease Control and Prevention
7. Treatment; Parasites- Enterobiasis (also known as pinworm infection); The Centers for Disease Control and Prevention
8. Ann E. Lloyd, et al.; Treatment Options and Considerations for Intestinal Helminthic Infections; The United States National Library of Medicine
9. Resources for Health Professionals; pinworm infection; The Centers for Disease Control and Prevention
10. Pinworm (threadworm) infection; health; Victoria State Government