1. Bridging social and biological sciences www.ucl.ac.uk/icls Noriko Cable, Mel Bartley, Anne McMunn, Yvonne Kelly University College London SLLS 2010, Cambridge

2. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Gender differences in the effect of breast feeding on adult psychological well-being Source: WHO

3. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Background WHO and UNICEF recommend exclusive breastfeeding for 6months. Established links between breastfeeding and physical health, extending to adulthood What about psychological health? Beyond childhood?

4. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls The theoretical model: BreastfeedingChildhood psychosocial adjustment Adult psychological ill health Adult self-efficacy

5. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Aims: To examine the role of breastfeeding on –childhood psychosocial adjustment –adulthood psychological well-being To compare the results are persistent between two British Birth Cohort Studies born 12 years apart

6. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Method: Participants: –NCDS (1958 cohort) Birth, age 7, age 11, age 33 Men (N=3,797); Women (N=3,953) –BCS70 (1970 cohort) Birth, age 5, age10, age30 Men (N=3,166); Women (N=3,326)

7. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Methods: Independent variables: –Breastfeeding 1 month+(=1), Never/less 1 mo (=0)

8. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Methods: Outcome variables: –Childhood psychosocial adjustment (2pt, top three quartiles =1, being adjusted) NCDS: Teacher assessed BSAG score BCS70: Teacher assessed Rutter score –Adult psychological well-being Psychological health –Malaise score 0-6 (=1, healthy), 7+ (=0, ill health) Self-efficacy –Cut off a total sum (3 items) into a 2pt (0=low, 1= high self- efficacy

9. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Methods: Confounders –Socio-demographic adversity index (0, not disadvantaged, 1=disadvantaged) Cut off at a median of the sum of: –Maternal education »Stayed in min. education=0, No=1 –Mothers age »Non-teen =0, teenage=1 –Parenthood »two parents=0, lone parent =1) –Being a first born child »no siblings =0, has siblings=1 indicated by parity

10. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Analysis: Logistic regression –Childhood psychosocial adjustment –Adult psychological well-being Compared the results by gender and cohorts

11. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: –Proportions of breastfeeding 1mo+ decreased 20% Mothers of BCS70 children breastfed for 1+ months –Most of the participants psychologically well childhood & adulthood –Breastfeeding practice appears to associate with social adversity

12. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: descriptive by cohort (Men) %

13. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: descriptive by cohort (Women) %

14. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: Childhood psychosocial adjustment UnadjustedAdjusted* BoysNCDS1.17(1.01-1.36)1.11(0.96-1.29) BCS701.18(0.96-1.45)1.14(0.93-1.41) GirlsNCDS1.30(1.10-1.55)1.25(1.05-1.48) BCS701.55(1.23-1.94)1.44(1.15-1.81) Note: adjusted for social demographic adversity

15. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: Girls appear to benefit from being breastfed more than 1 month. All effects were adjusted for social adversity

16. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: Adult psychological health UnadjustedAdjusted* MenNCDS1.03(0.78-1.37)0.97(0.73-1.29) BCS701.12(0.87-1.44)1.04(0.80-1.35) WomenNCDS1.26(1.03-1.54)1.17(0.95-1.44) BCS701.41(1.13-1.76)1.31(1.04-1.64) Note: adjusted for social demographic adversity+childhood psychosocial adjustment

17. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: Adult self-efficacy UnadjustedAdjusted* MenNCDS1.15(0.99-1.33)1.09(0.94-1.25) BCS701.15(0.94-1.40)1.06(0.97-1.30) WomenNCDS1.16(1.01-1.34)1.09(0.94-1.26) BCS701.44(1.17-1.78)1.31(1.06-1.61) Note: adjusted for social demographic adversity+childhood psychosocial adjustment

18. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Findings: A direct path from breastfeeding to childhood psychosocial adjustment –Supported among girls only A direct path from breastfeeding to adult psychological well-being (psychological health and self-efficacy) –Supported among women from BCS70 only. All effects were adjusted for social demographic factors and childhood psychosocial adjustment. Breastfeeding had no significant effects on mens outcomes.

19. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Discussion: –Gender differences in the findings, why girls/women? As a proxy for a mother-child relationship/attachment? Why not so important for boys after their infanthood? Why becomes so important to mid-childhood girls and adult women? –Can compare with the data from the MCS –Cohort effect, why BCS70? –Period changes in the contexts of social demographic factors? –Can compare with the data from the MCS

20. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Discussion: Limitations –Breastfeeding measures Not robust enough to assess dose-response relationships with the outcomes –Maternal education Not precise Social context of education Stayed in minimum age full time education or not

21. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Summary: The effect of breastfeeding on psychological health is limited –Not extensive as seen in physical health –Prevalent in women from the late cohort A path from breastfeeding to adult psychological well-being via child psychosocial adjustment

22. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Summary A direct path from breastfeeding to adult psychological well-being for the later cohort –For NCDS women A direct effect from childhood psychosocial adjustment via breastfeeding –Breastfeeding can be womens psychological well- being across lifecourse Policy implications –Encourage expecting mothers to take on and continue breastfeeding up to 6 months as recommended

23. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Acknowledgement: ESRC, UK data archive and CLS Thank you for listening! Contact: n.cable@ucl.ac.uk

24. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Descriptive: Men %

25. An ESRC Research Centre SLLS 2010 www.ucl.ac.uk/icls Descriptive: Women %