There is a problem in the modern world, I think: we honestly believe there is an answer to any question we ask if we pursue it with enough effort. It leads to unrealistic expectations and a suspicion that there should be no need to compromise -or if we do, a sense of disappointment that it was necessary. Medical knowledge seems to fall into this trap. We have come a long way, and yet how far there is still to go is often underestimated. Success comes in steady but often unpredictable increments, punctuated with unexpected retrenchments. It was hoped that sulpha and penicillin would mean the end of infectious diseases…
What brought this to mind are a series of papers warning against, for example, relying on supplements for chemoprophylaxis against –among other things- prostate cancer, osteoporosis, and Alzheimer’s disease. There still seems to be no adequate substitutes for exercise, a good healthy diet, or more probably, good genes. For many things we just don’t yet have any answers –except, maybe, healthy lifestyles. No compromises. No shortcuts. Just when we think we have it figured out, we find that we only were in possession of a portion of the answer –what constitutes wise choices for healthy living, for example… Sometimes we wander onto the wrong track altogether.
An area in which this is particularly important, is prenatal care. After all, those things that might make sense for the adult mother, may not generalize to her foetus. An obvious example is alcohol. Small amounts consumed outside the framework of pregnancy have a long body of evidence suggesting safety in the adult. Of course even this evidence is now suspect in light of data linking alcohol to a higher incidence of breast cancer. But in pregnancy, even small amounts may have a detrimental effect on the developing foetus. The problem, of course, is that there seem to be many other factors playing a role: metabolic differences from person to person, family to family; and different thresholds, or different consumption patterns that muddy the water sufficiently to allow all manner of interpretations and rationalizations about its use and safety in any or all trimesters.
The most recent studies have also questioned the safety of yet another medication we used to consider relatively safe for the foetus: acetaminophen (Tylenol is one of its brand names). http://www.huffingtonpost.ca/2014/02/24/acetaminophen-use-in-preg_n_4850454.html and a slightly different take on the evidence: http://www.huffingtonpost.com/2013/11/26/tylenol-during-pregnancy_n_4343319.html Of course there is often a need for analgesics from time to time –pregnant or not- but there are definite problems during pregnancy with the use of, say, ibuprofen or other NSAIDs –Non Steroidal Anti Inflammatory Drugs: kidney damage, internal bleeding, or even premature closure of a blood vessel, the ductus arteriosus that bypasses the (still unnecessary) lungs in the foetus. Even though the effect maybe transitory, it is probably best avoided. Aspirin (acetylsalicylic acid) can also lead to bleeding and has many similar effects to ibuprofen. So, what’s left for headaches? Morphine? Some other narcotic? No. Acetaminophen, while implicated in liver damage even in adults if overused, was felt to be safe for the foetus. It still probably is, and yet there is some evidence it may be linked to mood disorders and other more difficult to define problems in childhood. It can be, we have learned, an endocrine disrupter –something that might alter the effect or even normal production of hormones.
So what now? Suffer? Wait until the next miracle drug comes along and hope that it will prove safe in the long run? Well, I think that we’re going to have to accept that the use of medications in pregnancy is always going to be problematic. Risky. It is unethical, and totally unacceptable to run controlled experiments –whether blinded, or prospective (looking ahead to see what the results will be) on a developing foetus. Yes, there are animal models that can be tried –also with some ethical issues- but animals are not humans. The results may be misleading and not generalizable, or even applicable to humans. The most believable theories may eventually prove misguided. Or wrong.
Until we find another more satisfactory method of testing medications –complex computer simulations are an intriguing prospect- I suspect that most information in pregnancy will come by using retrospective data –that is, someone (or a great number of people) inadvertently used something and by good fortune, nothing happened to their babies. But the problem with this evidence is obvious. Not a sufficient number of cases may have been reported to make the information useful. The people using the medication may have had different characteristics that might alter the results for the rest of us. Or, they might have been just plain lucky! Worse –because we might be lulled into accepting the apparent safety of their use- the effects on the baby may not be apparent for months or years to come. Maybe that’s what is currently being described with acetaminophen –although the authors and others have recommended caution in interpreting their data for much the same reasons.
No, I think that for some time to come, we are going to have to look at medication consumption –especially in pregnancy- using a risk-benefit framework. There will always be some risk, but does the benefit override it? Some things with known risks carry an even greater likelihood of serious illness to the mother if they are not used in her pregnancy –antirejection medications for women with kidney transplants, are one fairly obvious example. There, the risk is likely worth it. It has been similarly argued that antidepressants in some women are essential to prevent either worsening depression and the consequences that it might have on good antenatal care, or even suicide…
But not everything requires an immediate solution; not everything requires medication. And it’s helpful if every once in a while, someone calls attention to this -and the fact that nothing should be considered completely safe in pregnancy. Maybe we should concentrate on trying to frame the risk in a fashion that is readily assimilable. Understandable for everybody.
We already have a system that assigns risks of medications in pregnancy from A (generally acceptable, with controlled studies in pregnant women showing no evidence of risk to the foetus) all the way to D (use in life-threatening emergencies only when no other safer drug is available; There is positive evidence of human foetal risk). There is even a class X (Do not use in pregnancy –the risks outweigh any potential benefits. Use something else!)
People are becoming more aware of this classification system as they look their prescriptions up online. It is up to the prescribing doctor or midwife to simplify it even more for them if necessary. Often that involves putting it into context.
We need a similar classification system that applies to new evidence as well, so that health care professionals can be confident that their information is both timely and reasonable. It serves no one well if the patient or the professional jumps to unwarranted conclusions based on inadequate evidence, or a poorly performed study.
Medicine is evolving quickly, but I think the most important change should be in the further education of both sides of the healthcare equation that there will always be risks. The unknown will never disappear. And it is naïve to insist that just because something can be framed as a question, there has to be an answer. Or even should be… Maybe that’s just the way it is sometimes…And I, for one, am frequently awed by the feeling of sheer speculative wonder, the mystery, of where geese go when they fly into a fog and their calls slowly fade into the distance. I will not frame it as a question.