“The data gap around pregnant women and medication is a huge problem,” says Dr. Christina Chambers, Professor of Pediatrics at the University of California, San Diego. “Lack of sufficient data leads to treatment decisions with no evidence base, and in some cases to avoidance of needed medication or to under-treatment. This can lead to complications because there is fear on the part of the clinician or the patient that a medication might be harmful.”
This data gap is something Dr. Chambers is working to redress as an active member of the Organization of Teratology Information Specialists (OTIS). OTIS aims to educate the public about exposures during pregnancy and breastfeeding through its service, MotherToBaby, at the same time as conducting its own observational research.
Women may choose to sign up to the OTIS studies after calling one of the MotherToBaby counselling services in the US or Canada with questions about exposures in pregnancy. Others join the study via general obstetric, family practice referral or directly through web, print, and social media advertising.
While recruitment is relatively simple, with women keen to both learn about their own issues and help others in the same position, one of the challenges of these studies is that they are often longitudinal, meaning children must be monitored as they grow to gauge any possible impact of medication taken by their mothers during pregnancy.
“For some studies, the child follow-up extends to 5-10 years or more, including neurodevelopmental and growth assessments at multiple time points,” says Dr. Chambers.
Longitudinal studies matter
Tapping into this need for data on pregnancy and medication to be longitudinal are the lifetime studies which follow participants from birth to death, taking regular measures of health as well as information about life factors such as career and family status. While studies of this kind do not recruit women based on having a particular condition or illness, data is collected about medications taken during pregnancy.
Lifetime studies are underway across the world and some are now many decades in. In the UK, the National Child Development Study began in 1958 while, in New Zealand, the Dunedin Multidisciplinary Health and Development Study began monitoring its participants in 1972.
More recently launched, the Avon Longitudinal Study of Parents and Children (Children of the 90s) study, based at the University of Bristol, UK, has been able to make links between medication taken during pregnancy and childhood health. Women were recruited during pregnancy and asked to fill in questionnaires about medication.
OTIS has been conducting studies for more than 30 years and has published numerous papers on outcomes following exposure to a wide variety of medications and other agents. In the US and Canada, thousands of women have taken part in studies around the safety of influenza vaccine in pregnancy, pertussis vaccine, asthma medications, and all of the medications used for the treatment of autoimmune diseases, including rheumatoid arthritis, Crohn's Disease, psoriasis, psoriatic arthritis, ankylosing spondylitis, and multiple sclerosis.
On logistics and funding
Long-term studies present practical challenges: not only are they costly, but keeping track of participants can be logistically tough.
“The two key issues in my opinion are funding – these studies are incredibly expensive to do well – and avoiding attrition by maintaining the cohort (maintaining up-to-date contact details),” says Dr. Kate Northstone, Head of Epidemiological Research for the Children of the 90s study.
The value of these time-consuming, lengthy studies is vast and it is vital that their unique data on pregnancy and medication be used.
“To my knowledge nobody has yet looked at the differences between social groups and medication use during pregnancy [within the Children of the 90s study] and at the moment there have been no policy implications based on this data, which is clearly underused,” says Dr. Northstone.
The OTIS MotherToBaby studies have had some direct influence over patient and provider decisions – for example with influenza vaccination (which led to pregnant women being more reassured about the safety of the vaccine during pregnancy), but Dr. Chambers believes more needs to be done to utilize and disseminate its findings.
“We urgently need to find more effective methods of translating and communicating results of such work to pre-pregnant women, pregnant women, and their providers,” she says.
A huge amount of work goes into these studies and it does indeed seem crucial that the results are as widely publicized as possible. After all, very real life-decisions are at stake for the thousands of women who must balance pregnancy with a need for medical treatment.