Okay, so I have done my research now.
Tylenol pm contains diphenhydramine, and acetaminophen.
Acetaminophen is used to reduce pain and fever. Unlike nsaids (nonsteroidal anti-inflammatory drugs), it lacks anti-inflammatory activity. Acetaminophen is available by itself or in nonprescription and prescription-only combination products used to relieve pain and the symptoms associated with colds and flu.
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.
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Diphenhydramine is an antihistamine used to relieve allergic rhinitis (seasonal allergy) symptoms including sneezing, runny nose, itching, and watery eyes and to relieve itching and swelling associated with uncomplicated allergic skin reactions. It is also used as a short-term sleep aid, to control coughs due to colds or allergy, and to prevent/treat motion sickness. Diphenhydramine is available in nonprescription products alone and in combination with other nonprescription drugs, to treat symptoms of allergy, colds, and upper respiratory infections.
Diphenhydramine may cause uterine irritability or contractions near term when used in high doses (greater than 50mg)
in 1974 saxen reported that a study group of 599 infants with oral clefting were more likely to have been exposed to diphenhydramine during the first trimester than a control group of infants without clefting. Subsequent retrospective studies of more than 2300 infants have found no association between first trimester exposure to diphenhydramine and oral clefting or major malformations.
Stillbirth has been reported following the use of diphenhydramine and temazepam during human pregnancy. The toxicity of this combination was confirmed in pregnant rabbits.
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Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

there is no information available about the safety of this medicine during pregnancy. It is not recommended for use during pregnancy. Seek medical advice from your doctor.

this medicine may pass into breast milk. It is recommended to avoid the use of this medicine when breastfeeding. Seek medical advice from your doctor.
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therefore, I wouldnt take it if I were you. But hey, do what you want.