Saturday 9 March 2013

The study of monsters: a perfect area for more critical thinking.

(Teratology: Noun: The scientific study of congenital abnormalities and abnormal formations. From the Greek teras [meaning monster or marvel] and logos [meaning study])

"Hands up, who is afraid of advising someone takes a medicine in pregnancy?"

In the couple of training sessions I've delivered, this has been my opening line. And many hands go up. I regularly give advice on medicines in pregnancy in my job, and it strikes me that it is an area which could hugely benefit from more critical thinking and a reliance on evidence in everyday medical practice. I'm thinking might do a little series of blog posts on this subject.

So why are so many people afraid of giving advice? One word: thalidomide. You'll all probably know what went wrong in the thalidomide disaster- a drug that was commonly used for morning sickness which unfortunately causes limb malformations when used at the time of pregnancy when women get morning sickness. That, coupled with the lack of post-marketing regulation ad monitoring back in those days- led to a perfect teratogenic storm, with obvious impacts for those affected, but which also shook the medical profession to its core. The good thing is that it forced a rethink in medicines regulation and triggered interest in pharmacovigilance, with schemes like pregnancy registries, teratology information services, and the MHRA's Yellow Card scheme being introduced in its wake. It's also left a lasting, deep-rooted fear of the potential of medicines to cause harm in pregnancy in pharmaceutical companies, patients and medical professionals alike.

Why is this fear a problem? Well, primarily because some pregnant women do still get ill, and do still need medical treatment. I've lost count of the number of times I've heard a doctor say to me "my patient has (insert life threatening disease) and she's found out she's pregnant, so I've stopped all of her meds. What harm will that have caused?" And my first response is "how is your patient?", along with having to try very hard to stop myself saying "what do you think is going to be more of a teratogen, whatever the drug is, or having a patient who is dead?!" Such decisions to stop treatments are often done without consulting any evidence first, and there is a clear potential for harm to patients and their pregnancies in such situations.

Another harm is that, in the event of something going wrong in a pregnancy, there's a tendency to way something to blame. I think it must be truly awful to have to think that because you have taken medicines, it's all your fault, especially as in many, many cases there will be no clear causality.

I think we can pretty safely say that, because of the things that have been put in place since thalidomide, that another similar disaster won't happen again. There are drugs which can undoubtedly cause harm in pregnancies but as with all things in medicine, we have to consider a benefit vs risk balance. And we have to take into account what evidence we have access to, think about its limitations, and apply it to each individual situation. Just stopping all medicines because a patient is pregnant is not going to be the least risky option in most cases (and indeed in all those aforementioned cases that I've discussed, the drugs the patient has been on have turned out to have some pretty reassuring data sets). I even know of a dr who panicked so much when he found out his patient was pregnant that he put a note through her door telling her to have an abortion because he had prescribe her some drugs which turned out to have a pretty robust safety record in pregnancy. Imagine the emotional harm this sort of thing could cause.

I don't want to end up writing a hugely long blog post so I'm going to end this one here as I'll cover some more aspects in future posts.