As part of this year’s campaign, running from the 17th to the 23rd of November, we sent Kory Stout to interview Faculty PhD student Sylvia Lui. Her project, led by Professor John Aplin and Dr Clare Towers and funded by the British Medical Association, looked at the effect of alcohol on pregnancy during the first-trimester. It was the first time that such a study had focused on this early stage of pregnancy. Sylvia says:
“It appears that alcohol, even at moderate levels, reduces the growth and function of the placenta resulting in less support and nutrient supply for a rapidly growing baby. It was interesting to find, though, that ethanol at very low concentrations (1-2 units, equal to half or one standard drink) did not have any effect on placental growth or function. Unfortunately, people find it difficult to judge what a unit is and often underestimate how much they are drinking, so erring on the side of caution may be the best practice.”
The team hope to conduct a much larger study in the future. Because guidelines on alcohol intake are often contradictory and confusing, they hope to produce some more specific advice to pregnant women about the individual dangers that they and their babies would be subject to through drinking alcohol.
You can read the whole interview over at the Life Sciences Blog.
Working in partnership with Tommy’s [a UK based charity that supports research into problems in pregnancy] and funded by the British Medical Association, we decided to look at the impact alcohol had on placental growth and function, and hence fetal development. My project, led by Dr Clare Towers and Prof John Aplin, looked at the effect of ethanol and its metabolite acetaldehyde on first-trimester pregnancy. We wanted to see if there was direct scientific evidence that would support the existing medical advice of avoiding alcohol consumption during pregnancy.
Why did you choose first-trimester pregnancy?
Although there are many studies on the effects of high levels of alcohol through the duration of pregnancy, this is the first time a study has shown the effect of alcohol in such an early stage. Previous research has centred on fetal outcomes at the end of pregnancy after massive levels of alcohol intake. Whilst this is obviously very important, we believed that understanding the effects of alcohol at the very early stages, when the fetus is at its most crucial stages of development and all the organs are just being programmed, was crucial in understanding the overall effects of alcohol in pregnancy and on fetal health.
How did you go about investigating the effects of alcohol on the developing fetus?
We are very fortunate to be working here at the Maternal and Fetal Research Centre at St. Mary’s hospital, one of the UK’s largest human placenta research centres. We are in an unparalleled situation in terms of having access to donated placental tissues and all of the work we did here was done in the laboratory and on donated tissue samples. The placenta was used as a means of assessing the potential effects on the development of the fetus because of its crucial role in providing nutrients and oxygen during pregnancy. Poor placental development is very strongly linked with poor fetal development and risk of fetal death. With the documented detrimental effects of alcohol, we were interested in how it would affect very early pregnancy, when the pregnancy is less likely to be known and more alcohol consumed.
To test the effect of alcohol on the placenta, we incubated the placental tissue with low (equal to half to one standard drink), mid (2-3 standard drinks), and high (4-6 standard drinks) levels of ethanol and acetaldehyde (the major metabolite of ethanol). After doing this, we measured the amount of vital amino-acids (including taurine) taken up by the placenta, that would act as markers of nutrient transfer for good fetal development. We then wanted to see if the levels of ethanol and acetaldehyde would affect the growth of the placenta. If they did, we could then draw conclusions from this about the consequent effects on the development of the fetus.
What were the results of your research?
The biggest and most surprising effect we found was that mid to high levels of both ethanol and acetaldehyde had detrimental effects only on taurine transport. Taurine is an important amino acid that is vital for normal brain development. In extreme cases of babies born with fetal alcohol syndrome, infants are often diagnosed with lifelong neurological problems. There are documented negative effects on behaviour and physical development with extended low taurine levels. Our results may indicate how alcohol can affect the baby’s brain development during pregnancy via the reduced placental transport of taurine to the fetus. Another important finding was that the same middle to high levels of ethanol and acetaldehyde also reduced placental cell growth.
In summary, it appeared that alcohol, even at moderate levels, reduced the growth and function of the placenta and resulted in less support and nutrient supply for a rapidly growing baby. It was interesting to find, though, that ethanol at very low concentrations (1-2 units, equal to half or one standard drink) did not have any effect on placental growth or function. Unfortunately, people find it difficult to judge what a unit is and often underestimate how much they are drinking, so erring on the side of caution may be the best practice.
Ideally, we would be able to do a much larger study. We want to see what alcohol’s effects are on a range of specific attributes. Advice on alcohol intake is confusing and studies have shown that alcohol has varying levels of effects, depending on genetic/race factors, different body types, socio-economic backgrounds, and gender. We want to see how much these factors affect the detrimental effects of alcohol during pregnancy and so the development of the fetus. This would help us to give much more specific advice to pregnant women about the individual dangers that they and their babies would be subject to through drinking alcohol.
You can read the paper, entitled Detrimental effects of ethanol and its metabolite acetaldehyde, on first trimester human placental cell turnover and function, on PLOS ONE. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0087328