A recent study published in Anesthesiology, the official journal of the American Society of Anesthesiologists, examined opioid prescription rates among pregnant women and surveyed what research still needs to be done on opioids and pregnancy.
The study was authored by Brian Bateman, M.D., M.Sc., assistant professor at Harvard Medical School. He stated, “Nearly all women experience some pain during pregnancy. However, the safety of using opioids to manage their pain remains unclear. Ultimately, we need more data to assess the risk/benefit ratio of prescribing these drugs to women and how it may affect their babies.” For the study, he and his team examined data from a research database of women who were enrolled in a commercial insurance plan and delivered babies between 2005 and 2011. The database contained data from over 530,000 women with a median age of 31. They focus primarily on what types of pain were most frequently treated, how often opioids were prescribed, and how this varies geographically.
The most surprising statistic relates to how many women were prescribed opioids during their pregnancy. According to Bateman and his team, 14.4% of these women (or 76,742 women) were prescribed opioids at some point during their pregnancy. These prescriptions typically lasted less than a week in duration. Of the women who were prescribed opioids, about 40% have prescribed an opioid during the first and second trimester; 45% have prescribed an opioid during the third trimester, and 15% were prescribed an opioid three times or more during pregnancy.
These opioids were most commonly prescribed for back pain, with 37% of prescriptions being dispensed for that purpose. Other relatively common conditions that called for opioid prescriptions included migraine, abdominal pain, joint pain, and fibromyalgia. Several different opioids were prescribed, with the most common being hydrocodone (6.8%), codeine (6.1%), oxycodone (2.0%), and propoxyphene (1.6%). (These numbers in themselves point to how many different opioids there are on the market today.) And then these prescriptions did vary significantly by geographic region. The lowest rates were observed in the Northeast, with a prescription rate of 6.5% (among all women). The highest rates were observed in the South, with a prescription rate of 26.3%.
Pamela Flood, M.D., professor of anesthesiology, Pain and Perioperative Medicine at Stanford University, shared her comments on the use of opioids during pregnancy. “The risk to the fetus of short-term exposure to prescription opioids under medical supervision is difficult to assess and needs to be carefully examined in future studies.” She added that previous studies have offered contradictory evidence surrounding the issue, with some finding no link between opioid prescription and birth defects, and others finding links to defects such as hypoplastic left heart syndrome, spina bifida. and gastroschisis. Additionally, there has been a proven link between long-term opioid use during pregnancy and birth defects.
Edward A. Yaghmour, M.D., of the ASA Committee on Obstetric Anesthesia, had this to say on the issue: “We need to carefully balance medications given to the mother and the risk to her and her baby. For example, we would never stop giving anti-seizure medication or medication for diabetes; the danger in those situations is clear. With opioids, there are simply not enough data to have a clear answer. Untreated severe pain in the mother may also be harmful to the fetus.” He added that other treatments and therapies should be explored first before turning to opioids.