Acetaminophen Used During Pregnancy May Be Linked to Birth Defects
Acetaminophen, the main ingredient in the over-the-counter medication Tylenol, is widely used for mild to moderate pain and to reduce fevers. It has traditionally been considered “safe” for use during pregnancy and is used by over half of pregnant women worldwide and up to 65% in the U.S.
Newly released research shows that the medication may not be as safe as previously thought. Researchers who conducted epidemiological and experimental studies have found that fetal exposure to acetaminophen during pregnancy may increase the risk of certain birth defects including neurodevelopmental, reproductive, and urogenital disorders.
Birth defects and conditions which may be linked to Tylenol use in pregnancy include:
- Autism/Autism Spectrum Disorder
- Undescended testicles (cryptorchidism)
- Abnormal urethra opening (hypospadias)
- Other reproductive disorders
Tylenol Use During Pregnancy
Tylenol contains acetaminophen, also known as paracetamol or by the name “APAP”. Acetaminophen is also an ingredient in a number of over-the-counter medications such as cough and cold remedies and is an ingredient in certain prescription medications.
Over half of all pregnant women use acetaminophen for mild to moderate pain, as a fever reducer and as part of other over-the-counter medications. Tylenol has long been thought to be “safe” for use during pregnancy, and has been encouraged, partly because other OTC medications such as ibuprofen and aspirin have long been known to increase the risk of fetal abnormalities, some of which are severe.
While high fever in pregnant women can result in birth defect, most women take acetaminophen for other reasons such as aches, mild pain, or headache. For many women, Tylenol use is so common, it is not thought of as a true medication that can have possible side effects. Research is showing that acetaminophen may have more risk than previously thought.
In addition to new and current concerns about neurologic, reproductive, and urogenital disorders, previous research has also attempted to link Tylenol use to autism, ADHD, intestinal disorder, and other birth defects. It is thought that higher, more frequent doses which are used for longer periods of times may place women and their fetuses at greater risk.
Research Group Finds Possible Link Between Acetaminophen and Birth Defect
An international group of 13 scientists conducted a review of 25 years’ worth of clinical data and medical literature including epidemiologic and experimental research of acetaminophen use. The research, published in September 2021 issue of Nature Reviews Endocrinology, shows an increased risk of neurological, urogenital, or reproductive disorders in children born to women who used acetaminophen during pregnancy.
Specifically, acetaminophen exposure during pregnancy may increase the risk of:
- Perinatal – cryptorchidism (undescended testicles), reduced anogenital distance (AGD), both of which are genital malformations (in males) and may indicate higher risk factor for reproductive disorder later in life
- Childhood – ADHD, Autism Spectrum Disorder, hyperactivity, behavioral difficulties, slow language development (in girls)
- Adolescence – Early onset puberty (in girls), other reproductive issues (in boys)
The conclusion reached by the 13-member science group was that guidelines for acetaminophen use during pregnancy should be changed. The recommendations for change were echoed by a group of 91 physicians, scientists, and clinicians from a number of countries including Australia, Brazil, Canada, Israel, Scotland, the U.K., the U.S., and other countries of the EU.
New Recommendations for Acetaminophen Use During Pregnancy
The group recommends that pregnant women should not use Tylenol or acetaminophen during pregnancy unless it is medically necessary and that the medication should only be used at the smallest dose, for the shortest time possible.
These recommendations have been echoed in most medical settings both in and outside of the U.S. Pregnant women are advised to contact their health care provider before taking any medication during pregnancy.
Acetaminophen as an Ingredient in Medications
In addition to name-brand Tylenol and generic acetaminophen sold as pain and fever remedies, it is a common ingredient in other medications sold over-the-counter and in a number of prescription medications used mainly for pain treatment.
Examples of OTC medications containing acetaminophen:
- Tylenol
- Tylenol Cough and Cold
- Tylenol Sinus
- Excedrin
- DayQuil / NyQuil
- Theraflu
- Robitussin Multi-symptom
- Coricidin
- Advil Dual Action
- Generic or store brand products
Because the medications are so common, the science groups are recommending that women who are pregnant be advised to “forgo” acetaminophen use whenever possible and to only use it at the lowest dose, for the shortest time when it is medically necessary. Manufacturers of popular over-the-counter medications have advised that women who are pregnant contact their health care provider before taking any medication.
Johnson & Johnson, manufacturers of Tylenol, may be facing thousands of lawsuits filed by people whose children may have been harmed but acetaminophen use during pregnancy.