Dr Wendy Jones MBE, Author, and Pharmacist
I was born above a community pharmacy. The daughter and niece of pharmacists before me, there was never any doubt about what I “wanted to do when I grew up”. When I had my daughters, I became equally passionate about breastfeeding, quickly afterward deciding to qualify as a breastfeeding peer supporter. It changed my life. Perhaps unsurprisingly I combined my two passions and started researching the compatibility of various medications with breastfeeding. I wrote a leaflet for National Childbirth Trust (NCT) and allowed them to share my home phone number, offering to answer any questions readers might have. With hindsight, that might not have been the best of ideas, but it started me along a very different route.
As a mother of three and working as a locum pharmacist, I began a Ph.D. project comparing the experiences of mothers, pharmacists, and GPs around breastfeeding and medication. My passion grew to educate professionals when reading comments such as “If a mother insisted on breastfeeding when she needs medication, I would report her to social services”. I heard from mothers still heartbroken having felt forced to stop breastfeeding against their wishes and my heart went out to them. I found websites and books that presented research on drugs that pass into breast milk. These studies might have been small but someone somewhere had taken the time to publish their findings.
Over the last 22 years, I have written a lot of information about common conditions experienced by breastfeeding women, from treating threadworms and providing pain relief to having an MRI scan. I was at one stage messaged by 10,000 people a year over various social media outlets and by email. The stories on occasion were heart-rending. It felt as though many professionals saw no difference between breast milk and commercial formula. Opting for the latter when a new mother was on medication. There was a perceived risk surrounding the level of drug passing to the baby and a lack of understanding of the pharmacokinetics of how drugs pass into breast milk. Until fairly recently this was a topic not covered by undergraduate education. Instead, professionals learned this “on the job”, provided they had a mentor who happened to be informed. Some professionals learned only once they had their own baby and encountered an issue. I wish I had £5 for everyone who told me “I didn’t get it until I had my own baby”.
Let’s take a step back and look at the evidence available for drug levels passing to babies through breast milk. In most published papers there are less than 20 babies exposed to a medication via milk, where levels of a drug are measured in the milk and outcomes for the baby are recorded (usually only for a few days). Why? This is vastly different from the studies required for pharmaceutical licenses which is why the standard patient information leaflet (PIL) in every box of tablets/creams etc says “Do not use if you are breastfeeding” or “Ask a health professional before using this product if you are breastfeeding”. It just means they aren’t required to take responsibility because they haven’t been able to do the studies. When I worked as a practice support pharmacist to GPs I looked at studies with many thousands of participants involved. Does this mean that the breastfeeding studies aren’t valid? No, it doesn’t. The reports are usually accompanied by pharmacokinetic data on the drug which provides a theoretical picture of transfer. Pharmaceutical companies don’t finance studies into the amount of their drug passing into milk, with very few exceptions. It is extremely hard to source funding for these studies elsewhere.
There is also a publication bias on research into drugs in breast milk. If a practitioner studies a group of mothers on drug x and the babies feed normally, gain weight normally, and show no adverse events would it be worth the time and effort to write and publish a paper? In most cases, it doesn’t happen because scientific journals, like most media, prefer something “interesting” to have happened. So, the outcome of the group of mother and baby dyads is lost to our knowledge unless the researcher is particularly keen and determined to share the information.
A paper in the Pharmaceutical Journal in December 2022 commented that “Often the only information on medicines and breastfeeding emanates from small case series or pharmacokinetic studies and is therefore a suboptimal evidence-base for advice”. My heart sank. This is a battle I have been fighting for almost 30 years. Has it all been for nothing? Is the theoretical risk of continuing to breastfeed greater than the known disadvantages of substituting breast milk for commercial formula? The authors continued “Currently, there are insufficient data to predict which infants will be harmed, in the short or long term.” We do have a paper that clearly states that serious acute adverse drug reactions and other adverse events from drugs in breast milk appear to be uncommon.
As I look at my precious grandchildren I know why I have been so passionate about breastfeeding and medication.
According to Public Health Scotland, in 2021-22 65% of babies in Scotland received breast milk after delivery but only about 46% continue to be given any breast milk beyond 6- 8 weeks (with only about 28% of those fed exclusively with breast milk). No research has revealed what proportion of the 35% entirely ruled out breastfeeding as an option because of concerns about their medications harming their babies – or what proportion of the 54% of early discontinuers stopped because of the same misapprehensions. The guidelines from the WHO are that babies should be exclusively breastfed for 6 months, so current statistics suggest we are failing our future generation. According to the Infant Feeding Survey 2010, of those mothers who give up breastfeeding within the first week, 80% said that they would have liked to feed for longer but were unable, presumably not having had access to effective support. Of these, 7% stopped breastfeeding because they were ill or on medication. This figure is the same for those who stopped before 6 weeks. The percentage of women who have chronic conditions apparently accelerated four-fold between 2009 and 2013. How many of these women had children and breastfed, we do not know. I am hopeful that this data will be provided by the Infant Feeding Survey carried out this year. What we do know is that breastfeeding mothers take fewer medications than those who use commercial infant formula, in some cases refusing medication in order to breastfeed.
From queries that I have received, frequently after a baby has been born, there have not been discussions about breastfeeding even where the mother has been on medication throughout pregnancy. I was surprised by the number of cases where a documented plan had not been put in place. I was recently contacted by a mother diagnosed with bipolar disorder. Despite having discussions before delivery, nothing had been recorded in her notes. She delivered over a weekend and no pharmacist was available to discuss her medication. The doctors and midwives said they couldn’t take responsibility and that it was her decision whether she “took the risk” to breastfeed her baby. So much for the importance of the first feed after birth and the amazing properties of colostrum! It could so easily have been rectified if something had been written in her notes. Despite having had the discussions antenatally about the compatibility of the medication in pregnancy and in breastfeeding this mother was left with a huge decision. Unsurprisingly she doubted herself. Thankfully she was supported by a third-sector volunteer but this certainly wasn’t the ideal position to be in considering her mental health diagnosis.
It’s clear why we discuss medication in pregnancy so carefully, most of us are all too aware of the adverse effects and premature deaths caused by Thalidomide in the 50s. Standard reference texts have historically been based on manufacturer recommendations and a lack of research. This poses a problem for mothers and professionals, who may consider commercial infant formula a safe alternative when considering the potential risks of breastfeeding whilst on medication. Unfortunately, this does not take into account the impact on the future health of the mother and baby. Whilst we don’t have the large clinical trials on medications taken during lactation, nor the funding to undertake them, we do have data on many individual drugs as well as a greater understanding of pharmacokinetics. There is a medication that is compatible with breastfeeding for most diseases. Noting cancer as a known exception.
As I look at my precious grandchildren I know why I have been so passionate about breastfeeding and medication. It has been wonderful and often humbling to fuel this advocacy with my professional knowledge so that I can help others.
My goal for the future is that every health professional understands how important it is to support women in their feeding choices. When a new mother wants to breastfeed and needs to take medication, this should be involved in her discussions with health professionals. There should be consideration of the available evidence from expert sources. No more knee-jerk reactions, instead a listening ear invested in the best outcomes for every mother and child.
Dr Wendy Jones MBE has been a Community Pharmacist for more than 40 years. She is the author of the texts Breastfeeding and Medication and Breastfeeding and Chronic Medical Conditions, both available to purchase online. You can read more of her work at www.breastfeeding-and-medication.co.uk