Back in May, IEU researcher Dr Gemma Sharp took part in Creative Reactions, an initiative that pairs scientists with artists to create artwork based on their academic research. With 50 artists and 50 scientists collaborating on works from sculptures and wood carvings to canvas, digital and performance art, the 2019 exhibition ran across two venues in Bristol.
Gemma was paired with Olga Trevisan, an artist based in Venice, Italy. They had conversations over Skype where they spoke about their work and formed some initial ideas about how they could combine their interests in a new way while remaining coherent to their own practices. Reflecting on the collaboration, Olga said, “I love how curious you can be of a subject you haven’t considered before. I believe collaboration helps to open your own mind.”
Based on some of the work around EPoCH, Olga created a piece called Beyond Question, which comments on the complexities of scientific data collection, bias and interpretation.
It poses questions around the pervasive assumption that pregnant women are more responsible for the (ill) health of their unborn children than their male partners are. Gemma and colleagues have argued that such assumptions drive the research agenda and the public perception of parental roles, by shaping which research questions get asked, which data are collected, and the quality of the scientific ‘answer’.
Beyond Question was presented in two phases at two separate exhibitions: during the first phase, people were invited to answer questions with a simple Yes or No using a stylus; leaving no marks but only invisible, anonymous traces on the surface below. Answers will reflect the real assumptions, beliefs and attitudes of the respondent, but perhaps also, despite anonymity, their eagerness to ‘please’ the questioners, to give the ‘right’ answer, and to mask their true responses to paint themselves in the ‘best’ light.
In the second phase, the questions were removed and the answer traces were left alone to carry their own meaning; free to be combined with the attitudes, beliefs and assumptions of the viewer and to be interpreted and judged in perhaps an entirely different way.
The questions posed were:
“Do you think a mother’s lifestyle around the time of pregnancy could be bad for her baby’s health?”
“Do you think a father’s lifestyle around the time of pregnancy could be bad for his baby’s health?”
“Before her baby is born, a pregnant mother shouldn’t be allowed to do unhealthy things, like smoke or drink alcohol. Do you agree or disagree?”
“Before his baby is born, a father shouldn’t be allowed to do unhealthy things, like smoke or drink alcohol. Do you agree or disagree?”
A novel thing about the Exploring Prenatal influences On Childhood Health (EPoCH) study is that we’re not just focusing on maternal influences on offspring health, we’re looking at paternal influences as well.
One of the reasons that most other studies have focused on maternal factors is that it’s perhaps easier to see how mothers might have an effect on their child’s health. After all, the fetus develops inside the mother’s body for nine months and often continues to be supported by her breastmilk throughout infancy. However, in a new paper from me and Debbie Lawlor published in the journal Diabetologia, we explain that there are lots of ways that fathers might affect their child’s health as well, and appreciating this could have really important implications. The paper focuses on obesity and type two diabetes, but the points we make are relevant to other health traits and diseases as well.
How could fathers influence the health of their children?
These are the main mechanisms we discuss in the paper:
Through paternal DNA. A father contributes around half of their child’s DNA, so it’s easy to see how a father’s genetic risk of disease can be transmitted across generations. Furthermore, a father’s environment and behaviour (e.g. smoking) could damage sperm and cause genetic mutations in sperm DNA, which could be passed on to his child.
Through “epigenetic” effects in sperm. The term “epigenetics” refers to molecular changes that affect how the body interprets DNA, without any changes occurring to the DNA sequence itself. Some evidence suggests that a father’s environment and lifestyle can cause epigenetic changes in his sperm, that could then be passed on to his child. These epigenetic changes might influence the child’s health and risk of disease.
Through a paternal influence on the child after birth. There are lots of ways a father can influence their child’s environment, which can in turn affect the child’s health. This includes things like how often the father looks after the child, his parenting style, his activity levels, what he feeds the child, etc.
Through a father’s influence on the child’s mother. During pregnancy, a father can influence a mother’s environment and physiology through things like causing her stress or giving her emotional support. This might have an effect on the fetus developing in her womb. After the birth of the child, a father might influence the type and level of child care a mother is able to provide, which could have a knock-on effect on child health.
What does this mean for public health, clinical practice and society?
Appreciating the role of fathers means that fathers could be given advice and support to help improve offspring health, and their own. Currently hardly any advice is offered to fathers-to-be, so this would be an important step forward. Understanding the role of fathers would also help challenge assumptions that mothers are the most important causal factor shaping their children’s health. This could help lessen the blame sometimes placed on mothers for the ill health of the next generation.
What’s the current evidence like?
In the paper, we reviewed all the current literature we could find on paternal effects on offspring risk of obesity and type 2 diabetes. We found that, although there have been about 116 studies, this is far less than the number of studies looking at maternal effects. Also, a lot of these studies just show correlations between paternal factors and offspring health (and correlation does not equal causation!).
What is needed now is a concerted effort to find out how much paternal factors actually causally affect offspring health. This is exactly what EPoCH is trying to do, so watch this space!
This content was reposted with permission from the EPOCH blog.
Kayleigh Easey, a PhD student and member of the Tobacco and Alcohol Research Group (TARG) at the School of Psychological Science at the University of Bristol, takes a look at a recent systematic review investigating effects of parental alcohol use and offspring mental health.
It’s generally well known that drinking large amounts of alcohol during pregnancy is linked to Foetal Alcohol Syndrome (FAS), and negative outcomes such as premature birth and an increase in the risk of miscarriage. However, less is known about the effects of low to moderate alcohol use during pregnancy on offspring outcomes after birth, and even less for mental health outcomes in the child, particularly internalising disorders such as depression. Despite government guidelines being updated by the Department of Health in January 2016, advising pregnant women that the safest approach is to abstain from drinking alcohol altogether through their pregnancy, there remains uncertainty amongst the public as to whether a ‘drink or two’ is harmful or not.
Is a ‘drink or two’ harmful during pregnancy?
Researchers within the field mostly agree that abstinence from alcohol during pregnancy is the safest approach, but the evidence to support this is relatively weak, often due to study design and sample limitations. A previous meta-analysis highlighted how there are relatively few studies investigating low levels of alcohol use in pregnancy. Their analyses mainly focused on pregnancy outcomes such as gestational diabetes and childhood outcomes linked to FAS such as behavioural problems. Until now, a comprehensive review had not been undertaken on the effects of light to moderate drinking in pregnancy and offspring mental health.
Our research sought to review and summarise what literature was currently available for drinking alcohol in pregnancy and offspring mental health outcomes. Overall, we found that over half of the analyses included in the review reported an association between drinking in pregnancy and offspring mental health problems, specifically anxiety, depression, total problems and conduct disorder. By excluding FAS samples we were more certain that the findings we were reporting were representative of lower levels of drinking in pregnant women. However, we can’t be certain that many of the included studies are not still capturing higher levels of alcohol use in pregnancy, and potentially children with undiagnosed foetal alcohol spectrum disorders – a known problem in researching prenatal alcohol use.
Our review also highlights the differences across studies measuring drinking in pregnancy and offspring mental health, with all but four studies using a different measure of drinking alcohol in pregnancy, making comparison difficult. This means it is difficult to establish between studies if there is a ‘cut off’ level for what is potentially a hazardous level of alcohol exposure during pregnancy.
Abstinence seems to be the safest approach
The associations we find do not provide evidence of a causal effect on their own, which can be difficult to demonstrate. However, it is important for women to understand what the current evidence shows, to allow them to make informed decisions about drinking during pregnancy. Women should be able to use this information to inform their choices, and to avoid potential risks from alcohol use, both during pregnancy and as a precautionary measure when trying to conceive.
As such, people may take from this that the current advice of abstaining from alcohol during pregnancy is certainly sensible, at least until evidence is available to indicate otherwise. We suggest that future work is needed to investigate whether light to moderate alcohol use in pregnancy may be harmful to different mental health outcomes in children from large cohort studies, which is exactly what I am currently doing within my PhD research using the Children of the 90s study.
For many years, researchers have been studying how our early life experiences, including those that happen before we are born, can affect our lifelong health. In an article we wrote last year, Debbie Lawlor (University of Bristol), Sarah Richardson (Harvard University) and I show that most of these studies have focused on the characteristics and behaviours of mothers around the time of pregnancy. In a recent paper published in the Journal of Developmental Origins of Health and Disease, Debbie Lawlor, Sarah Richardson, Laura Schellhas and I show that there have been more studies of maternal prenatal influences on offspring health than any other factors (read more here).
We argue this is because people assume that mothers, through their connection to the developing fetus in the womb, are the single most important factor in shaping a child’s health. This assumption runs deep and is reinforced at every level, from researchers, to research funders, to journalists, to policy makers, to health care professionals and the general public (see figure 1).
In our article, we question the truth behind this assumption.
Is there a strong scientific rationale for studying pregnant mothers so intensively?
Well, no actually. Although a lot of studies have found correlations between maternal characteristics and offspring health, the evidence that these characteristics actually have a causal effect is pretty weak. And since there haven’t been many studies of the effects of fathers and other factors, it’s difficult to say how important any maternal effect might be compared to any other early life experience.
Focusing so intensively on pregnant mothers, and interpreting all evidence as causal (if a mother does X, their unborn child will have Y), can have very damaging effects. Complex, nuanced scientific findings are being rushed into simplified advice that, although well-meaning, places the burden of blame on individual pregnant women. For example, there has been very little research on the effects of low-level drinking during pregnancy, but the current advice in the United States is for all sexually active women of reproductive age to avoid alcohol completely if they are not using birth control, for fear of fetal harm.
A culture of blame
The culture of blame is more overt in the media, where articles are often guilty of scaremongering. This feeds into public beliefs about how pregnant women should and shouldn’t behave, which can limit pregnant women’s freedom and even lead to questions around whether their behaviour is criminal. For example, pregnant women have reportedly been refused alcoholic drinks in bars, and taking drugs during pregnancy is legally classed as child abuse in many US states.
In our article, we make a number of recommendations that we hope will create more of a balance. In particular, we call for more research on how child health might be influenced by fathers and other factors, including the social conditions and inequalities that influence health behaviours. We also call for greater attention to be paid to how health advice to pregnant women is constructed and conveyed, with clear communication of the supporting scientific evidence to allow individuals to form their own opinions.
The EPoCH study
In June, I’ll begin work on a new project to investigate how both mothers and fathers’ lifestyles might causally affect the health of their children. Funded by the Medical Research Council, the EPoCH (Exploring Prenatal influences on Childhood Health) study will highlight whether attempts to improve child health are best targeted at mothers, fathers or both parents. I’m excited to work closely with the people behind WRISK to help ensure that findings from this project are communicated effectively and responsibly.
I hope that, along with the rest of the research community, we can produce high quality evidence to support health care and advice that maximises the health of all family members and stops blaming women for the ill health of the next generation.
Our full recommendations, which apply variously to researchers, journalists, policy makers and clinicians:
Collect more and better quality data on partners of pregnant women.
In addition to studying the effects of mothers, study and compare the effects of partners/fathers, social and other factors on child health.
Look for causal relationships between these factors and child health, not just (potentially spurious) correlations.
Publish all results, including negative results, to give a balanced view of the evidence.
Be aware and critical of the current imbalance in the scientific literature and how this will bias our overall understanding of the truth.
Collaborate with social scientists to consider the social implications of this research and the role of cognitive bias and social assumptions when interpreting findings.
When communicating findings, put the risk in context: compare findings to the broader scientific literature and the social environment.
Avoid language that suggests individual mothers are responsible for direct harm to their foetuses (most of the evidence will be based on averages in a population and can’t be assumed to apply to all individuals).
Where there is evidence of a paternal effect, aim public health advice at both parents.
Explain the level of risk in a way that empowers people to assess the evidence and form their own opinions (i.e. avoid over simplification).