Safety Testing Challenge – Drugs During Pregnancy

There is a real challenge when it comes to the ethics of testing the side effects of drugs that are taken during pregnancy. On the one hand, it is necessary to know the side effects and whether it is safe to take a drug, especially during pregnancy. On the other hand, is it ethical to expose an innocent and otherwise healthy fetus to the potential side effects of the drug. What to do?

The result is that little is done in the way of pre-market testing. That is, most drugs are not tested to determine if they are safe for the unborn. This means that there is a critical need to actively follow up with post market data collection and to aggressively look at that data to determine if there are dangerous side effects for the unborn child. It is important to gather this data accurately, and to act upon it quickly.

Such is the case with the recent analysis of data on Proton-Pump Inhibitors (PPIs) which are commonly given as a treatment for heart burn and acid reflux. Data from Denmark, that included every live-born infant in the country from 2005-2008, was reviewed to determine if there was an increase in birth defects as a result of antenatal exposure to PPI drugs. The study looked at 840,000 births and accounted for many potential confounding factors. With this large data set, the authors of the study determined that there is not likely to be any association between the use of PPIs and birth defects. This preliminary data is reassuring for those who have taken or are taking PPI drugs during pregnancy.

The findings are considered "preliminary" for a couple of reasons. Most importantly is that the authors were looking at all birth defects, which would mask a possible increase in any one birth defect. This is significant because, when a birth defect is caused by a drug, usually it is a specific birth defect (e.g. heart problems in the case of Paxil). Other reasons that these results need to be considered preliminary are that not all confounding factors were accounted for, and many different PPI drugs were included in the study. Again, both of these factors could mask any side effects of a particular drug or for a particular condition.

In conclusion, the authors found that:

In this large cohort, exposure to PPIs during the first trimester of pregnancy was not associated with a significantly increased risk of major birth defects. (Funded by the Danish Medical Research Council and the Lundbeck Foundation.)