As I write, I’m sat at my kitchen table, it’s 5:30 in the morning and I can’t sleep. I’m hot, I’m uncomfortable and I’m 38 weeks pregnant. Although I’ve luckily had a really good pregnancy so far (this is my first baby), I, like millions of other women I’m sure, felt overwhelmed and rather stifled when I first saw those two lines turn blue. Rewind 8 months and it was a miserable Thursday evening. The night before, we had an office party and I figured that, as I crawled into bed at 7pm, I was still nursing the tail end of a hangover. I woke a couple of hours later and it was my husband who urged me to take a test when I couldn’t finish the Thai takeaway he’d lovingly ordered. And that’s how I found out we were expecting a baby. Magical.
Next; post euphoria, queasiness and future planning, came A LOT of questions. The next morning I took my usual walk to the office, stopping at Pret to pick up a coffee. Nothing out of the ordinary there. It’s my morning routine. I like to start the day with a coffee. Just the one in the morning is sufficient to kick start my working day and keep me going. However, now that I’m pregnant, is that allowed? I couldn’t do anything about the drinks consumed or cigarettes smoked prior to finding out I was expecting, (sorry baby) but that was then and this is now. Smoking is a NO GO; but alcohol and coffee? 9 months without a glass of wine seemed excessive but back then, wine definitely was not at the forefront of my mind. It was the caffeine hit I was after and it was becoming increasingly URGENT.
Finding information on the internet about caffeine is easy. There are chat rooms, blogs, official recommendations from national organisations and recommendations from specialist doctors. Opinions are everywhere. Two a penny. The problem I found is that there’s a total lack of agreement on the matter. Recommendations differ not only across countries but also across books, obstetricians and GPs within the same country. In the UK, the National Institute for Health and Clinical Excellence advises healthcare professionals to tell their patients that 200 milligrams (about 475 millimetres) of coffee a day was OK. My obstetrician said no more than 300 milligrams although I should consider switching to decaf OR asking the barista about the strength of the caffeine in the coffee. She herself wasn’t a coffee drinker. The Mayo Clinic Guide to a Healthy Pregnancy* rules out any caffeine, in any amount.
Having read through some of the reports, it was clear to see that the medical findings were based on data. However they weren’t based on the same data or their interpretation of the data varied massively. Not much help there then.
What I did find was an article that, HOORAY, was based on an actual study that was thoroughly explained. To preface this, there was one main downside though, in that it was old news. The research was conducted between 2003 – 2006 and the article written in 2008, but it was all I could find and as yet hadn’t been updated or revised so it was the best conclusive piece of evidence that I could use to help me with my decision.
As reported in The Times, “Pregnant women are advised to drink no more than two cups of coffee a day to cut the risk of giving birth to underweight babies”. The newspaper said that new research (well from 2008) has led the UK Food Standards Agency to reduce its maximum recommended daily caffeine intake during pregnancy to 200 mg, roughly the amount in two cups of instant coffee.
This was a prospective cohort study. In it, the researchers looked at the association between the amount of caffeine pregnant women drink and the weight of their babies at birth. Previous studies have found that caffeine consumption during pregnancy is associated with reduced birth weight, but were unclear on what level of caffeine is associated with this effect.
To read the full article go to https://www.nhs.uk/news/pregnancy-and-child/caffeine-and-pregnancy/
The researchers conclude, “Caffeine consumption during pregnancy was associated with an increased risk of fetal growth restriction and this association continued throughout pregnancy. Sensible advice would be to reduce caffeine intake before conception and throughout pregnancy.”This relatively large and well-conducted study provides evidence of an association between caffeine consumption during pregnancy and low birth weight. The fact that caffeine intake from any source was assessed is another strength of this study. There are a few points to consider when interpreting the results:
- Only 20% of the women invited to take part did so, which is a relatively low rate. However, the researchers did not think that this 20% of women would differ from the general population, as the participants did not differ greatly from the overall population in the two maternity units.
- Women had to remember and report their consumption of foods, drinks, and medications containing caffeine and errors could have been introduced at this point. However, the periods they were asked about were relatively recent and not too long; therefore recall should have been relatively good. The fact that that the researchers used a standard questionnaire that had previously been tested increases the likelihood of getting reliable results. Also, the fact that caffeine consumption was assessed before the birth of the baby means that the women’s’ recollection would not have been affected by this knowledge.
- It is possible for studies of this type to be affected by factors that are unbalanced between the groups that are compared. For example, if caffeine did not affect birth weight, but women who consumed high levels of caffeine also drank more alcohol, then (as alcohol affects birth weight) an association between caffeine and birth weight would be found if alcohol use was not adjusted for (taken into account). The authors adjusted for factors that they knew might affect results, such as maternal smoking, alcohol use, and other maternal characteristics. These adjustments increase the likelihood that the association seen between caffeine and birth weight is real, but there may still be other factors which are having an effect that were not measured.
- The authors point out that being in the lowest 10% of birth weights does not indicate that there was necessarily anything medically wrong with the babies.
Having read and digested this I figured that on the one hand, it solved my immediate issue which was that yes, I could have my morning latte and feel OK about it. Phew! Although, it did open up a whole can of worms for me. Whilst I can trust the findings in this study to some extent, my biggest issue with it and with similar studies that look at the medical risk of food / drink consumption on an unborn baby, is that research, because of ethical reasons (and rightly so) is not allowed to be performed on pregnant women. What I mean is that the tried and tested method in medicine, a randomised trial, is not possible as it puts both the baby and mother at risk. You cannot take a group of pregnant women, randomly select half to give a high dose of caffeine to and the other a placebo and see what happens to their baby when it’s born. I think that this is why there are so many mixed messages about what is and isn’t allowed, what will and won’t harm your baby and it’s not just caffeine I’m talking about here, but all sorts of things. Alcohol, cheese, cured meats, unpasteurised milk, uncooked egg yolk and then there’s an extensive list of medications. Ibuprofen, indigestion tablets, even decongestants! Perhaps if I was able to take half a Nytol I wouldn’t be awake now! Anyhow, and it goes I am. It’s now 6:25 AM and actually, I feel about ready for my morning cup of coffee…