[Insights into pregnancy and breastfeeding in inflammatory rheumatic diseases through observational data]

Information on pregnancy and breastfeeding in women with chronic inflammatory rheumatic diseases is relevant for a successful pregnancy and also for maternal and child health. In general, pregnant and breastfeeding women are excluded from randomized clinical trials and therefore evidence for clinical care and counselling has to be generated from observational studies. In the past decades, various data collections have been established for this purpose in addition to the existing spontaneous reporting systems initiated by drug authorities, with the aim of monitoring the teratogenic risk of a drug. Health insurance claims data, electronic health records and Scandinavian registers are also increasingly being used for research on pregnancy-associated events; however, all these data sources lack the inclusion of the maternal disease, especially with respect to its inflammatory component. Established cohort studies, biologics and disease registries record disease activity but are not designed for pregnancy-specific questions. Pregnancy registries and studies in rheumatology close this gap. In order to be able to make a better assessment of the possibilities and limitations of existing data sources on pregnancy and lactation, they are presented in detail in the following review including their respective advantages and disadvantages and examples from rheumatology are given. In addition, existing collaborations as well as studies for investigating the influence of paternal rheumatic disease are highlighted.