Fig. 4
High-risk medical conditions or procedures in medical history* leading to exclusion from LR cohort. AP, All Pregnancies; AP24+ , All Pregnancies with gestational age ≥ 24 weeks; LR, Low-Risk pregnancies; N, number of pregnancies in the corresponding group/category; CMV, cytomegalovirus; COPD, chronic obstructive pulmonary disorder; HBV, hepatitis B virus; HCV, hepatitis C virus; HIV, human immunodeficiency virus. *All available medical history prior to start of pregnancy through 240/7 weeks gestational age (see Additional file 2 for algorithms and assessment periods)