Sara Öberg

I am interested in the causes and consequences of reproductive challenges. The vast majority of my work is collaborative, involving individual experts and working in teams and larger networks.

Reproduction is the beginning of life, and the time we spend in utero inarguably the most important developmental period of our lives. Disruptions
or insults during this critical time could, through direct or downstream effects, impair offspring health both in the short and long-term. My research
spans across the whole the range of sensitive periods, from pre-conception through pregnancy up to labour and delivery, and concerns the health of both mother and child.

Infertility and fertility treatments
Involuntary childlessness is prevalent and increasing in many countries, and approximately 5% of births in the Nordic countries were conceived with
assisted reproductive techniques. The potential consequences on maternal and offspring health are still not fully known, due to lingering methodological issues but also limited large-scale long-term follow-up. Rigorous evaluation is required to establish whether potential adverse effects are due to the treatments or rather their indication (and associated risk factors). In the last years we have looked into the long-term health of children conceived with ART, contributing also to an international collaborative effort to do so across several countries (LIFT Study), and we are currently moving to evaluate the impact of ART on women's cardiovascular health. I am also involved in UppStART [1] - the "Uppsala-Stockholm Assisted Reproductive Techniques study" is a prospective cohort study of couples undergoing infertility treatment (specifically IVF or ICSI) in the greater Stockholm and Uppsala municipalities. Participants were recruited from three of the four fertility and reproductive health clinics in Stockholm and one clinic in Uppsala, which also serves a large volume of patients from Stockholm.

Prescribed drug use
Studies of the safety of prescribed drug use are similarly challenged by the need to disentangle the treatment effect from the role of the underlying condition (confounding by indication). Collaborative efforts to study offspring health following maternal use of psychotropics in pregnancy are currently undergoing substantial upscaling to allow the study of both safety and effectiveness of various prescribed drugs in pregnancy, using more advanced and detailed exposure characterisation and a new register linkage with maximised follow-up. In this I am particularly interested in the extension to evaluate what influence prescribed drug use can have on the ability to conceive and maintain pregnancy among women receiving fertility assistance.

Family designs
To make meaningful inference from observational data, and ultimately identify modifiable risk factors, it is vital to understand and address threats to study validity and in particular the influence of confounding. In my thesis work I used twins to exclude the potentially confounding influence of shared genetic and environmental factors on well-established associations between birth weight and adult health outcomes such as cardiovascular disease and breast cancer. I have since then moved to use siblings and other relatives to understand the influence of factors shared in families. While the ability to target otherwise unmeasured confounding is an attractive feature that has to be balanced against specific assumptions and limitations, and I am proud to contribute to an effort to identify, formalise and contextualise this in a series of methods papers on the sibling comparison design.

Academic positions
Postdoc research fellow (2011-2016), Harvard T.H. Chan School of Public Health
Assistant professor (2016-2020), Karolinska Institutet
Adjunct assistant professor (2016-2021), Harvard Chan School
Principal investigator (2020-), Karolinska Institutet
Adjunct associate professor (2022-2027), Harvard Chan School

Current co-workers and students

Chen Wang, research specialist (2023-)

Cina Nyberg, PhD-student Kliniska Vetenskaper DS, KI (2020-)
Angelo Mezzoiuso, MEB, KI (2022-)
Anne Brynolf, PhD-student KEP, KI (co-advisor 2019-)
Pauline De Corte. PhD-student, Charité Universitätsmedizin Berlin (co-advisor 2021-)
Mujin Ye, PhD-student, Onk-Pat KI (co-advisor 2022-)
Emma Cleary, PhD-student, Indiana University (co-advisor, 2022-)

Balram Rai, PhD-student, MEB, KI (co-advisor, 2022-)

Lisa Kogner, PhD-student, KEP, KI (co-advisor, 2023-)

Charlotta Riese, PhD-student, Onkologi-Patologi, KI (co-advisor, 2023-)

Previous co-workers and students

Franziska Fischer, research assistant, MEB, KI (2023)

Mina Rosenqvist, assistant professor MEB, KI (2020-2023)

Chen Wang, PhD-student MEB, KI (2017-2022)
Ayesha Sujan, PhD-student, Indiana University (co-advisor)
Kelsey Wiggs, PhD-student, Indiana University (co-advisor)

Medical Degree Project at Karolinska Institutet: Davide Attebrant-Sbrzesny (17’), Eva Skärby (18’), Linnea Lin (19’), Theo Ekholm, Julius Martin
and Edwin Råsberg (20’), Tilda Agild and Astrid Östholm (22'), Elin Trulsson and Jenny Näsholm (23')

MPH Practicum at Harvard Chan School of Public Health: Rossana Calderon and John Lowery (19’), Mausumi Das, Anuj Pareek and Alexandra
Puchwein-Schwepcke (20’), Matthew Carawana and Kelly Nichols (21’), Daniel Rolnik (22'), Jennifer Yo (2023)

Funders

National Institutes of Health, Forte, the Swedish Research Council, Fulbright, Karolinska Institutet, Lennander’s stiftelse, Wallenius’ stiftelse, and Iris.

Instructor in Analytic Methods for Epidemiologists, Harvard Chan School 2016 -
Shared course instructor in Epidemiology I, Karolinska Institutet 2020 -
Lecturer [Causal mediation analysis] in Epidemiology III, Karolinska Institutet 2018 -
Grading instructor Systematic Reviews and Meta-analysis, Harvard Chan School 2016
Lecturer [Research synthesis] in Clinical Data Science, Harvard Medical School 2016