It may not be safe to use pseudoephedrine in pregnancy, however, women should consult their doctors prior to making a final decision. Taking this drug during the first trimester of pregnancy has not been conclusively linked to any harmful birth defects. The US Food & Drug Administration (FDA) does not believe that enough conclusive testing on human patients has been conducted to rate the drug as safe, and does not recommend that pregnant women use it.
In the US, pseudoephedrine has been given a pregnancy rating of Category C. Category A is given to drugs that have been tested extensively and have failed to show any signs of damage to the mother or the fetus during either the first trimester, or any subsequent period of the pregnancy. Drugs receive a Category B rating that have been tested on pregnant animals and shown no evidence of harm to the mother or baby, but have not been tested on any human pregnant patients. Category C is given to those drugs that have harmed the mother or the fetus during pregnancy in animal studies, and that have not been tested on any human pregnant patients. Categories D and X are reserved for those drugs which are known to cause fetal abnormalities and can jeopardize the health of the mother, in both human and animal testing.
The Category C rating assigned by the FDA regarding the use of pseudoephedrine in pregnancy indicates that the benefits of the drug to the mother may, in some cases, outweigh the possible side effects. Animal testing, while a precursor to human testing, does not always produce the same results. A pregnant rat may birth a deformed baby when given pseudoephedrine, while a pregnant human mother taking the same drug births a perfectly formed and healthy baby. The risks associated with this drug during animal testing, however, may make extensive trials in human patients unlikely.
The possible side effects of using pseudoephedrine in pregnancy include gastroschisis and small intestinal atresia. Gastroschisis is a condition caused by the failure of the baby's abdominal wall to close completely during development. This opening is typically beside the umbilical cord, and some of the baby's intestines may push through the opening. This condition is detectable by ultrasound, and can be corrected through surgery performed relatively soon following birth.
Small intestinal atresia occurs when a portion of the small intestines either closes or disconnects during fetal development. This condition can also be detected by ultrasound, or diagnosed immediately upon birth. Newborns with this condition often have a large, distended stomach that indicates the inability of waste to pass through the intestines. This type of defect is generally corrected through surgery soon after delivery.
These illnesses are only conditionally associated with the use of pseudoephedrine in pregnancy and are not conclusively linked with the drug. Other medications and genetic factors cannot yet be overlooked in those cases where these defects have been detected. The fetus completes the majority of its muscular, neural, and skeletal development during the first trimester of pregnancy. Some doctors may feel that taking this medication during later stages of pregnancy, such as the second or third trimesters, pose less of a risk to the baby, and provide a significant benefit to the mother, and may recommend its use for their patients.