AU professor takes over management of national birth cohort

From 1 May 2024, Professor Cecilia Ramlau-Hansen from the Department of Public Health at Aarhus University will be heading the Danish National Birth Cohort, which contains unique health data from approximately one-third of all children born in Denmark in the period 1996-2003 and their mothers.

Professor and Head of Section Cecilia Ramlau-Hansen forsker i årsager til forstyrrelser af det reproduktive helbred med fokus på fostertilstanden, ofte med udgangspunkt i data fra kohorten Bedre Sundhed i Generationer som hun nu skal stå i spidsen for.
Professor and Head of Section Cecilia Ramlau-Hansen researches the causes of disorders of reproductive health with focus on the foetal stage, often on the basis of data from the Danish National Birth Cohort, which she will now be heading. Photo: Privat

Facts about the Danish National Birth Cohort

  • The Danish National Birth Cohort (DNBC) consists of data such as questionnaires and blood samples.
  • The purpose of the DNBC is to generate more knowledge about how the pregnancy period and early childhood affect the health of the mother and child in order to improve preventive efforts for pregnant women and their children.
  • During the period 1997-2004, the DNBC collected data on more than 100,000 pregnant women and their babies. The extensive data material provides unprecedented research opportunities in Denmark.
  • The size of the cohort makes it possible to study interactions between factors such as lifestyle, infections, medical treatments, environmental conditions and congenital (rare) birth defects. Data from the DNBC will also be able to shed light on the causes of diseases that first occur later in life.
  • Researchers from different professional groups (e.g. midwives, health visitors, doctors, dentists, sociologists and psychologists) can apply for access to data from the project. This requires that the researcher has a project that has been approved by the health research ethics committees, the Danish Data Protection Agency and by the DNBC scientific management group and reference group.
  • The oldest “children” in the DNBC turned 18 in autumn 2015. The researchers contacted all of the cohort's young participants and asked them to decide whether they wanted to continue participating in the DNBC. Only a few opted out, and this provides the basis for new studies – also when the young people start their own families.
  • The cohort’s reference group consists of the deans of health sciences in Denmark, including Aarhus University’s own Dean of Health Anne-Mette Hvas, and the chairman of the reference group is Henrik Ullum from Statens Serum Institut (SSI). The reference group also includes representatives of the Danish Epidemiological Society (DES), Independent Research Fund Denmark and the DNBC group of participant ambassadors.
  • In 2023, 52 new publications were based on data from the DNBC, and the DNBC publication list now counts 764 publications. In addition, 59 PhD dissertations have been based on DNBC data since the start of the project. See the full list of publications via The National Library of Medicine.


What you (maybe) didn't know about Cecilia Ramlau-Hansen

The professional stuff:

  • Her scientific work has particular focus on sperm count, puberty development and infertility. Among other things, she investigates whether the things a foetus is exposed to (e.g. endocrine disrupting substances, the mother's lifestyle and health) can have an effect on the child's reproductive organs, puberty development, sperm count, hormones, fertility and infertility.
  • Has published 210 original articles and reviews within reproductive epidemiology.
  • Received the faculty's supervisor award, the JCD Prize, in 2017. In the recommendation for the award, her PhD students wrote: "Cecilia Ramlau-Hansen is a source of inspiration both in achieving academic goals and in relation to balancing a family life with a career in research. With her behaviour, she shows us how we can become good supervisors one day."
  • Has Jørn Olsen, emeritus professor at the Department of Public Health, as her scientific role model: "He’s a brilliant epidemiologist who is known and respected all over the world. He was an ingenious visionary, not least when he took initiative to establish the DNBC, and I and my research group - as well as many other researchers in Denmark and abroad - are still reaping the benefits of his efforts," Cecilia Ramlau-Hansen says.
  • Is primary investigator for the ERC-synergy project BIOSFER, which received DKK 104 million to investigate causes of low fertility in 2023.
  • Is head of section and part of the department management team at the Department of Public Health.
  • Is one of the faculty's 12 career ambassadors.  

The private stuff:

  • Is married to Søren, who is a primary/lower secondary school teacher. They live in Hobro and are parents to sons Mikkel, Emil and Oskar aged 28, 23 and 15, respectively.
  • Has previously practiced elite gymnastics, won the Aalborg championship several times, and has also worked as a youth coach.
  • As a student, she worked as an aerobics, spinning and fitness instructor at a gym.

The quirky stuff:

  • Born in 1970 in Sweden and has a Finnish father and a Danish mother. Her father came to Denmark to study medicine at AU in the 1960s, where he met her mother, who worked at the School of Dentistry.
  • Has a twin sister and is one of four children.
  • Meditates and exercises as often as she can – it gives her energy.
  • I think pizza and a good beer on Friday night is the best way to end a good week at work.

Read more about Professor Cecilia Ramlau-Hansen in the articles "Health-professor receives DKK 104 million for fertility research", "Following your dream comes at a price", "PhD student honours dedicated professor" and "Reach out to your local career ambassador".

The Danish National Birth Cohort (DNBC) is an invaluable data resource for researchers around the world. This is the opinion of Professor and Head of Section Cecilia Ramlau-Hansen, who is the newly appointed principal investigator of the cohort. And she justifies this by the fact that the DNBC contains information about a large group of people's development and well-being as well as their health and diseases from the foetal stage, through childhood, adolescence and now into adulthood. Among other things, the cohort makes it possible to study causal links, i.e. factors affecting health, in a lifetime perspective.

"We have a very comprehensive and unique set of data; a representative sample of an entire country's population, which we can combine with the national registers we have in Denmark. For example, we can couple data from the cohort with information in the Danish National Patient Register. This is only possible in very few places in the world," explains Cecilia Ramlau-Hansen.

She hopes that, as the theprincipal investigator of the cohort she can inspire even more colleagues, both within and outside AU, to make use of the DNBC data in their research in the future.

Strong Aarhus University representation in the cohort

Dean Anne-Mette Hvas is part of the cohort’s reference group together with the other health deans in Denmark. She is pleased with Health's strong representation in the cohort's management group and sees enormous potential.

"I'm proud that researchers from our faculty were part of the very beginning of the Danish National Birth Cohort, and that a researcher from Health has been represented in the scientific management group ever since," she says, and continues:

"The national birth cohort is a goldmine of valuable health data. And I really wish that even more researchers would see the possibilities of the cohort. The data is invaluable, not only for our research here at Aarhus University, but also for research into public health in general. Therefore, it means a lot that we can influence the development of the cohort and strengthen its potential. I’m convinced that Cecilia Ramlau-Hansen is the right person for the job."

The cohort will soon contain unique health data from three generations

The DNBC was established as a basic research centre in 1994 to investigate health and diseases, including physical development, physical health and mental health, in a lifelong perspective.

The purpose was, and still is, to generate knowledge to form the basis for preventive efforts, and more than 100,000 pregnant women originally participated in the cohort. In the beginning, focus was on mothers and their foetus/child – and only to a limited extent on fathers. Now the children, approximately 92,000 young women and men, have grown up and are starting their own families. This means that the cohort is expanding organically with additional data from and about the participants' pregnancies and children.

"This data resource is becoming more and more valuable over time. The cohort will soon contain three generations. The first third-generation babies have already been born, and my most important task as the principal investigator of the cohort for the next three years will probably be to include the third generation, i.e. the grandchildren, in the cohort," says Cecilia Ramlau-Hansen.

The willingness of participants is crucial

"This cohort is only possible because the participants are still willing to participate in our studies – primarily by answering questionnaires, but also by providing blood and semen samples. We’re all deeply grateful for the participants' time, openness and dedication. As many as 30-35 per cent of all Danish children born between 1996 and 2003 from all over Denmark are included in the cohort. This is incredibly valuable health data."

Cecilia Ramlau-Hansen was selected by the rest of the scientific management group, which consists of researchers from Aarhus University, Statens Serum Institute, the University of Copenhagen, the University of Southern Denmark and the Capital Region of Denmark, to take over management of the cohort from Professor Anne-Marie Nybo Andersen from the University of Copenhagen. Cecilia Ramlau-Hansen will be responsible for ensuring that the management group is moving in the same direction, that the cohort is used for the purpose for which it was originally intended, and that the research lives up to the very highest standards.

"I look forward to representing the DNBC as the principal investigator of the cohort. Virtually all my research is based on data from the cohort, and I feel great responsibility to take good care of both the cohort and its participants. As the principal investigator of the DNBC, I also have access to some scientific and political forums that I’ve not been a part of before. I still don't know what doors the cohort can open, but I'm very excited," concludes Cecilia Ramlau-Hansen.


Professor and Head of Section Cecilia Ramlau-Hansen
Aarhus University, Department of Public Health
Telephone: (+45) 26 29 57 15