Table 4

Summary of SEP indicators' association with maternal and infant's outcomes, effect of adjustment on each association, income and education-related inequalities in the ALSPAC 1991/92 and in the 1982, 1993 and 2004 Pelotas cohorts and trends in inequalities in the Pelotas cohort studies

Outcomes	Crude association between SEP indicator and outcome		Effect of adjustment in the association between SEP indicator and outcome		Income-related inequalities	Education-related inequalities	Trends in inequalities in Pelotas cohorts
Outcomes	Income	Education	Income	Education	Income-related inequalities	Education-related inequalities	Income	Education
Ever smoked during pregnancy	Inverse (higher among the poorest)	Inverse	Moderate effect: ALSPAC & 2004	Moderate effect: ALSPAC & 2004	ALSPAC >> Pelotas	ALSPAC≈2004	No trends	Increasing
Ever smoked during pregnancy	Inverse (higher among the poorest)	Inverse	Small effect: 1982 & 1993	Small effect: 1982 & 1993	ALSPAC >> Pelotas	ALSPAC & 2004 > 1993	No trends	Increasing

Caesarean section	Positive (higher among richest)	Positive	Almost no effect in all cohorts	Almost no effect in all cohorts	Pelotas>ALSPAC	Ø ALSPAC	No trends	No trends
Caesarean section	Positive (higher among richest)	Positive	Almost no effect in all cohorts	Almost no effect in all cohorts	Pelotas>ALSPAC	1982≈1993≈2004	No trends	No trends

Delivery not attended by a doctor	Inverse	Inverse	Almost no effect in ALSPAC	Almost no effect in ALSPAC.	Pelotas>ALSPAC	Pelotas 1982 & 1993>ALSPAC	Decreasing	Decreasing
Delivery not attended by a doctor	Inverse	Inverse	Some effect in Pelotas cohorts	Moderate effect in Pelotas cohorts	Pelotas>ALSPAC	Pelotas 1982 & 1993>ALSPAC	Decreasing	Decreasing

Intrauterine growth restriction	Inverse	Inverse	Almost no effect in all cohorts	Almost no effect in all cohorts	1982 > other cohorts	ALSPAC ≈ Pelotas	Decreasing	No trends
Intrauterine growth restriction	Inverse	Inverse	Almost no effect in all cohorts	Almost no effect in all cohorts	ALSPAC ≈ 1993 & 2004	ALSPAC ≈ Pelotas	Decreasing	No trends

Preterm birth	Inverse (no association in 1982 cohort)	Inverse (no association in 1982 cohort)	Almost no effect in ALSPAC	Moderate effect in ALSPAC.	Ø in 1982	Ø in 1982	Increasing	Increasing
Preterm birth	Inverse (no association in 1982 cohort)	Inverse (no association in 1982 cohort)	Small effect in Pelotas cohorts	No effect in Pelotas cohorts	ALSPAC ≈ 1993 & 2004	Pelotas 2004 > ALSPAC	Increasing	Increasing

Breast feeding for less than 3 months	Inverse (no association in 1982 & 1993 cohorts)	Inverse (no association in 1982 & 1993 cohorts)	Moderate effect in ALSPAC	Almost no effect in any cohort	Ø in 1982 & 1993	Ø 1982 & 1993	No trends	Increasing
Breast feeding for less than 3 months	Inverse (no association in 1982 & 1993 cohorts)	Inverse (no association in 1982 & 1993 cohorts)	Almost no effect in Pelotas cohorts	Almost no effect in any cohort	ALSPAC > Pelotas 2004	ALSPAC >> 2004	No trends	Increasing

Ø, no inequalities; ≈, similar magnitude; >, high; >>, much higher; SEP, socioeconomic position.