Is this safe in pregnancy?! Will this medication hurt my baby? If I don't take this medication, what exactly is the risk to my unborn baby? These and other questions related to what medications are safe to use in pregnancy are some of the most commonly asked in OBGYN offices around the world. This month's Green Journal features a series of three related articles about the interesting topic of drugs and pregnancy.
Dr. Chescheir, editor of the journal, introduces the series with an editorial in which she highlights the fact that the Food and Drug Administration (FDA) recently changed the way they label prescription drugs for pregnant women. Since June 30, 2015, the old A-B-C-D-X labels are a thing of the past. The consensus was that these labels were confusing to most providers and patients and implied that C is worse than B and so forth, when it really means that we simply don't have as much information about the drug's safety. Now the FDA gives specific information for three classes of people: pregnant women (including when they're in labor), nursing mothers, and men and women who have the potential of reproducing ("of reproductive potential"). The FDA provides the risks identified for each drug for these groups of people. Over time we will see if providers and patients find this new method more or less confusing and if it changes practice patterns.
The question follows: did the FDA categories influence what drugs pregnant women received? Did providers totally avoid Category D and X drugs? In the second article, researchers from UC San Diego and Harvard School of Public Health ask just this question. They used data on all the outpatient prescriptions dispensed from Medicaid records from 2000-2007 that included all pregnant women who had Medicaid prior to becoming pregnant. Excluding fertility treatments, 42% of the women had filled at least one prescription that was FDA Category D or X during their pregnancy. Looking at the data on all medications, antibiotics were the most common with 21.6% of women taking nitrofurantoin (commonly used for urinary tract infections- UTI) and 19.4% taking metronidazole (commonly used for bacterial vaginosis- BV). In all, 82.5% of pregnant women were dispensed at least one prescription drug during their pregnancies. So, what was the post popular Category D drug? Narcotics. 11.9% of women received codeine and 10.2% received hydrocodone. In total, 27.1% of women received a narcotic prescription during pregnancy.
Is this a problem? Dr. Kremer and Dr. Arora from Case Western argue, in their commentary article about opioid abuse in pregnancy, that opioids have no proven teratogenicity. They argue that the most dangerous side effect of opioid addiction in pregnancy is withdrawal, which is linked to miscarriage, the placenta detaching from the uterus (placental abruption), the baby being born before 37 weeks (preterm birth), and stillbirth. The authors argue that the best way to treat opioid addiction in pregnancy is to provide compassionate, nonjudgmental care and understand how to administer opioid maintenance therapy (methadone or buprenorphine- found in suboxone or subutex). They site research that showed that pregnant women enrolled in maintenance therapy were less likely to relapse and those without it were more likely to withdraw in the hospital, leading to further complications, and high relapse rates. Most of us immediately wonder: how do babies do with opioid maintenance therapy? The biggest risk to the baby is also withdrawal, known as neonatal abstinence syndrome. This can be severe and lead to lengthy hospital stays. Preliminary research suggests that buprenorphine (subutex) may be better in this respect, but how severe the neonatal abstinence syndrome is depends on the dose of opioids being taken during the pregnancy. Certainly these considerations necessitate an interdisciplinary approach between the patient, obstetrician, addiction/substance abuse expert, neonatologist, and pediatrician. Surely an individualized approach to maximizing the health of mothers and infants will be most effective.
In all, this series of articles highlights one interesting aspect of caring for pregnant women: providing prescription medications. We are still in the early stages of the new FDA system and only time will tell how our understanding of opioid use in pregnancy will develop.