When used according to directions, acetaminophen (the active ingredient in Tylenol) is considered safe for pregnant women.
Care providers typically recommend acetaminophen for almost every ache and pain experienced in pregnancy. It has a long record of safety.
Page Two: Learn more about acetaminophen use during pregnancy
If pain or discomfort is a problem in pregnancy, your care provider should investigate the reason. Headaches may be relieved with, massage, stress reduction, rest, application of cold or heat or even a cup of coffee. (Headaches are often caused by normal physiological process of vasodilation and a small amount of caffeine might be enough to relieve the headache.)
If acetaminophen is necessary in pregnancy, it should be used only for short-term therapy and it would be wise to take only one or two tablets or capsules every eight hours in order to stay well under the recommended adult dosage.
The safe adult maximum dose for acetaminophen is four grams over a 24- to 48-hour period. Most capsules or tablets contain 325 mg. This means that a maximun dose would be equal to approximately 12 tablets. A maximum dosage could easily be reached if two tablets are taken every four hours. Considering that other products may also contain acetaminophen, it is likely that the maximum dose could be easily exceeded.
Despite its safety record, studies continue to be conducted to evaluate the possibility of adverse effects of using acetaminophen during pregnancy. One such report by Thulstrup et al, published in the American Journal of Perinatology, vol. 16(7), 1999, investigated fetal growth and possible adverse birth outcomes in women receiving prescriptions for acetaminophen during pregnancy. Results showed there was no excess risk of malformation and no evidence that acetaminophen adversely influenced fetal growth.