The following potential confounders were investigated: antenatal depression
at 32 - week gestation (Edinburgh Postnatal Depression (EPDS) score, Cox and Holden 1994), postnatal depression
at 8 weeks (Edinburgh Depression Score), maternal education
at 32 - week gestation (CSE or below, A
level, degree), breastfeeding
at 6 months (never, stopped, still feeding), gender (male / female), number of siblings
at 6 months, marital
conflict at 8 months (Rutter and Quinton 1984), homeowner
at 8 months (yes / no), type of dwelling
at 8 months (detached, semi-detached, terraced house, flat / maisonette, rooms, other), neighbourhood
at 8 months (very good / good / not very good), social class (1 — 6), maternal age
at time of delivery,
multiple pregnancy
at time of delivery and single - parent status
at 8 months (single / partner).