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Developmental biology - Fetal Cystic Fibrosis

Cystic Fibrosis Babies Weigh Less At Birth

Research shows cystic fibrosis impacts fetal growth in the womb...

Research conducted by CF-EpiNet - a Cystic Fibrosis Trust Strategic Research Center (SRC) of which the University of Liverpool in the UK is a member, reveals that CF results in low average birth weight, and a need for more research on how CF is affecting infant development in the womb.


The research team compared babies born with and without CF from data on 2.2 million babies born in Denmark and Wales. The research published July in Thorax and funded by the Cystic Fibrosis (CF) Trust, indicates that though babies with CF are often born prematurely, this only accounts for around 40% of such low birth weights. The CF mutation may also be affecting babies' development in the womb. Babies born to financially disadvantaged families also tend to produce lower weight babies at birth, regardless of whether or not they have cystic fibrosis. Thus functions of both socio-economic inequality and CF may begin in the intrauterine period.


CF-EpiNet SRC allows researchers to use, as well as add data to, the Trust's UK CF Registry. The registry informs patients and researchers about what happens at birth and what happens living with cystic fibrosis. The current study begins with the Wales and Denmark databases to investigate and study the effects of socio-economic deprivation on CF patient outcomes.


Poor nutrition and slow growth are common features in babies with CF. Both can impact a baby's lung function and future survival. Adds Rebecca Cosgriff, Registry Leader: "Currently, we do not know how birthweight affects future health. The next stage of the research will be to link databases used in this study with the UK CF Registry. This will add in more CF-specific information and may give us further insight."

"A direct result of this study could be that birthweights are added to data collected by the UK CF Registry either by people with CF or their guardians, who choose to share. By investigating possible links between factors that cause low birthweight and adult health outcomes, we hope to find ways to address inequalities and give parents of babies with CF hope for a brighter future." explains Professor David Taylor-Robinson, Co-Principal Investigator, University of Liverpool, UK.

Impact similar to smoking

"Our study shows the importance of data linkage for child health. Using datasets linked across different resources, we can see over two million children in two countries and see that CF has a large effect on birth weight, similar to the impact maternal smoking makes during pregnancy. These results show that having CF impacts directly on intrauterine growth. More research is needed to understand the biological mechanisms for this, and to assess how birthweight predicts survival for people with CF. From a clinical perspective it is important to optimise support for children with CF right from the start of life "

Poor growth during infancy and childhood is a characteristic feature of cystic fibrosis (CF). However, the impact of CF on intrauterine growth is unclear. We studied the effect of CF on birth weight in Denmark and Wales, and assessed whether any associations are due to differences in gestational age at birth.

We conducted national registry linkage studies in two countries, using data for 2.2 million singletons born in Denmark (between 1980 and 2010) and Wales (between 1998 and 2015). We used hospital inpatient and outpatient data to identify 852 children with CF. Using causal mediation methods, we estimated the direct and indirect (via gestational age) effect of CF on birth weight after adjustment for sex, parity and socioeconomic background. We tested the robustness of our results by adjusting for additional factors such as maternal smoking during pregnancy in subpopulations where these data were available.

Babies with CF were more likely to be born preterm and with low birth weight than babies with no CF (12.7% vs 5% and 9.4% vs 5.8% preterm; 11.9% vs 4.2% and 11% vs 5.4% low birth weight in Denmark and Wales, respectively). Using causal mediation methods, the total effect of CF on birth weight was estimated to be -178.8 g (95% CI -225.43 to -134.47 g) in the Danish population and -210.08 g (95% CI -281.97 to -141.5 g) in the Welsh population. About 40% of this effect of CF on birth weight was mediated through gestational age.

CF significantly impacts on intrauterine growth and leads to lower birth weight in babies with CF, which is only partially explained by shorter gestation.

Daniela K Schlüter, Rowena Griffiths, Abdulfatah Adam, Ashley Akbari, Martin L Heaven, Shantini Paranjothy, Anne-Marie Nybo Andersen, Siobhán B Carr, Tania Pressler, Peter J Diggle, David Taylor-Robinson

The authors would like to acknowledge all the data providers who make anonymised data available for research.

The authors also acknowledge the support from The Farr Institute of Health Informatics Research. The Farr Institute is supported by a 10-funder consortium: Arthritis Research UK, the British Heart Foundation, Cancer Research UK, the Economic and Social Research Council, the Engineering and Physical Sciences Research Council, the Medical Research Council, the National Institute of Health Research, the National Institute for Social Care and Health Research (Welsh Assembly Government), the Chief Scientist Office (Scottish Government Health Directorates), the Wellcome Trust (MRC Grant Nos: CIPHER MR/K006525/1, HeRC MR/K006665/1)

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Aug 7, 2018   Fetal Timeline   Maternal Timeline   News   News Archive

Poor growth during infancy and childhood is a characteristic feature of cystic fibrosis (CF).
However, the impact of CF on intrauterine growth is not well understood. The effect of CF
on birth weight was assessed in Denmark and Wales. Image Credit: March of Dimes

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