Fig 1. Flow chart of study- population and design.

¹ Not all women from the source population were asked to participate in the study while still pregnant, partly for practical reasons and partly due to exclusion criteria (unable to understand Norwegian). ² 2 BS and 16 FFQ missing at random or passive dropout. ³ Women recruited 2–6 weeks postpartum to restrict selection bias as not the whole source population was asked to participate during pregnancy due to practical reasons. ⁴ Passive drop-out sometime between T1 and T2. ⁵ 18 BS and 16 FFQ missing at random or passive drop-out. ⁶ 21 BS and 21 FFQ missing at random or passive drop-out. ⁷ 30 BS and 26 FFQ missing at random or passive drop-out. BS: blood sample; FFQ: food frequency questionnaire.