Pregnancy and Common Medications and Substances
From Encyclopedia of Sex and Sexuality
In the United States the average pregnant woman may ingest from three to seven different drugs in the course of her pregnancy. Many common drugs can cross the placenta and enter the circulation of the developing baby. While only a few have been shown to directly cause birth defects, very little information is available on the effects of most drugs on the fetus and even less is available on the potential long-term effects of these drugs. Given the large number of over-the-counter drugs currently available, it becomes the responsibility of every pregnant woman to consider her own use of drugs.
The best rule of thumb is that a woman who suspects she is pregnant use no prescription or over-the-counter medications without first consulting her obstetrician. The potential for severe birth defects tends to be higher the earlier during pregnancy that a drug is used (See also Fetal and Infant Substance Abuse Syndromes).
 Commonly Used Drugs
A short list of commonly used drugs is discussed below. This list employs generic names. In some cases, these drugs may be more popularly known by a brand name.
Acetaminophen is commonly used during each trimester of a pregnancy to control pain and lower fevers. Appropriate usage, as recommended on the label, is apparently safe. Acetaminophen does cross the placenta, but no birth defects have been associated with this drug. However, continuous high doses cause fetal liver and kidney problems.
Aspirin is probably the most commonly used over-the-counter drug during pregnancy. Some studies have shown adverse effects including maternal anemia, prolonged pregnancy, prolonged labor, and excessive bleeding at delivery. Fetal effects may include impaired blood clotting ability and hemorrhage into the brain in a preterm infant. Aspirin should be avoided during pregnancy.
Caffeine does cross the placental barriers but no evidence establishing a relationship of caffeine use to birth defects has been found. Some studies have shown an association between high caffeine consumption (six to eight cups of coffee per day) and miscarriage as well as low birth weight infants, but these studies are not well supported.
No reports have associated ibuprofen use with congenital defects. However, use of this drug has been shown to prolong pregnancy. In addition, a theoretical risk of ibuprofen includes a change in fetal heart circulation. Therefore, the manufacturer does not recommend usage during pregnancy.
Many different antacid preparations are currently available, These include buffered calcium carbonate, magnesium, and aluminum hydroxide. These have not shown any harmful effects to the fetus. However, care should be taken because many of these preparations are high in salt. Furthermore, use of them may lead to diarrhea or constipation.
 Cold Medicines
There are many over-the-counter cold medications that contain an antihistamine and/or a decongestant.Two such drugs, Cyclizine and Pseudoephedrin, are commonly used during pregnancy. Studies have linked both drugs to congenital defects, including cleft lip and club foot; however, those studies are not well supported. Therefore, it is prudent to avoid these drugs during the first trimester of pregnancy when possible. Furthermore, continuous high doses should be discouraged.
 Artificial Sweeteners
Questions often arise regarding the safety of artificial sweeteners used during pregnancy. No congenital defects have been linked to the usage of these products; however, moderation is certainly advisable.
 Antifungal Medications
Yeast infections are extremely common throughout pregnancy. Medications commonly taken to control them have not been found to cause birth defects. Care, however, should be taken when applying these medications into the vagina.