I welcome Dr Tom York to the blog, NHS-registered and private GP for GPDQ, the UK’s first doctor-on-demand app to share his insight. Here he shares his views on whether painkillers in early pregnancy are dangerous.
Medication for pain relief is widely used. The British population spent £566.5 million on over-the-counter analgesia between July 2017 and July 2018 equating to about £8.50 per person. Paracetamol and ibuprofen accounted for the vast majority of these sales. They’re readily available from pharmacies, supermarkets and corner shops; they’re very cheap, and they’re highly effective for the treatment of fevers and mild to moderate pain.
However, the safety of ibuprofen along with other prescribed NSAIDs (non-steroidal anti-inflammatory drugs) has been of concern for many years. They are well known to cause stomach irritation which can sometimes lead to life threatening gastric ulceration. They can damage the kidneys and exacerbate breathing problems in people with asthma. It’s also known that NSAIDs used in the third trimester can lead to the premature closing of a vessel which links the two large vessels exiting the heart, potentially causing foetal death. But despite this, they are a very useful class of medication for treating inflammatory conditions from muscle sprains to arthritis.
Miscarriages are unfortunately very common. It’s estimated that 1 in 8 pregnancies will end in miscarriage but this figure only takes into account women who know they are pregnant. The chance of pregnancy ending due to miscarriage before four weeks is 1 in 4 but many women won’t have realised that they were pregnant before the miscarriage has taken please. Thankfully, miscarriages become less likely as the pregnancy progresses with the risk of miscarriage at 12 weeks dropping to 1.7%. Many factors increase the risk of miscarriage including maternal age, smoking, alcohol, caffeine and also medication. However, it’s important to remember that in many cases, there is no clear cause found and there’s nothing which could have been done to stop it.
Miscarriages and NSAID use
Several studies have looked into an association between NSAID use and miscarriage. NSAIDs block the production of substances called prostaglandins which animal studies have found to be necessary in the successful implantation of an embryo into the wall of the uterus. The theory sounds sensible but it’s important for researchers to demonstrate this link in humans before countries can issue guidance advising women to avoid this medication and potentially denying them treatment which could benefit them in other ways, namely in reducing pain.
In 2001 there was a large Danish study published which demonstrated an associated risk between NSAID use in pregnancy and an increased risk of miscarriage. The study found an increased risk of miscarriage between 2.7 and 7 times greater in those women who took NSAIDs.
A smaller study was carried out in California in 2003 and found the risk of miscarriage in their group was 1.8 times greater. They also reported that the risk was higher if the medication was taken around the time of conception or if it was taken for more than one week.
Another large study, this time in Canada in 2011, found an increased risk of miscarriage 2.4 times greater in those taking NSAIDs but did not find that the dose affected the risk.
The largest study of all was carried out in Israel in 2014 and did not find any association between NSAID use and miscarriage.
What does this mean?
There is unfortunately no consistent message to be taken from the above studies. The reason for this could be that each study only looked retrospectively at groups of women who had become pregnant, then gathered data regarding the outcomes of those pregnancies and tried to determine those who had used NSAIDs.. The two main issues with this are firstly; as mentioned above, many miscarriages are missed, especially when very early in the pregnancy, so these women would not have been included in the studies. The second is that ibuprofen is widely available over the counter, so trying to determine which women took NSAIDs and for how long can be very difficult.
As is often the case with medical research; further studies are required to confirm or refute the theory.
The Royal College of Obstetricians and Gynaecologists (RCOG) released an article in 2018 giving some useful advice. They suggest all medication should be avoided in the first trimester if possible. But, if analgesia is required, paracetamol should be used preferentially. NSAIDs should not be taken unless clinically indicate. For example, someone suffering from severe migraines, forms of arthritis or high fever may need to use this medication.
In my opinion, the logical reasoning why NSAIDs might increase miscarriage rates, combined with the positive findings of some of the studies, leads me to agree that NSAIDs should only be used in early pregnancy when absolutely necessary and when there is no safer alternative. If you’re planning for a baby, avoid taking NSAIDs if possible. If you happen to fall pregnant and then realise you’ve taken some ibuprofen in the previous few weeks, there’s no benefit to worrying about it. Just don’t take any more, allow nature to take its course, and in the sad event that you do miscarry, try not to dwell on the possible reasons, take time to look after yourself and your partner and try again once you’re ready.
Read Dr York’s guide to breastfeeding HERE.