Fig. 1.

Flowchart of the study population of women born between June 1983 and August 1988, who gave birth to their first child at age 14·5 to 27·5 years. *Women excluded because they gave birth during the 15-month wash-out period from June 1985 to September 1986. †Births where the woman was either below 14·5 or above 27·5 years of age, the offspring’s birth weight was misclassified, gestational weeks was <22 weeks or pre-pregnancy BMI was <15·46 kg/m². ‡Excluded due to missing information on age at delivery, smoking habits, singleton and multiple births, gestational age at delivery or offspring gender. §Group 1, gestational hypertension; ICD-10 code: O13.9. ║Group 2, mild to moderate and unspecified pre-eclampsia; ICD-10 codes: O14.0 and O14.9. ¶Group 3, severe pre-eclampsia, HELLP syndrome and eclampsia; ICD-10 codes: O14.1, O14.2 and O15.0 (ICD-10, International Statistical Classification of Diseases and Related Health Problems 10th Revision; HELLP, haemolysis, elevated liver enzymes, low platelets)