Association Between Maternal Smoking and Breastfeeding at 10 Weeks

1
Association Between Maternal Smoking and
Breastfeeding at 10 Weeks

• Kenneth D. Rosenberg, MD, MPH
• Zhiwei Yu, MPH
• Alfredo P. Sandoval, MS, MBA
• Oregon Office of Family Health
• Portland, Oregon
• 8th Annual MCH Epidemiology Conference
• December 13, 2002
• Clearwater Beach, Florida

2
Introduction

• Maternal smoking
• Associated with decreased breastfeeding
• Hakansson et al. (Scand J Prim Health Care
  19921060-65) 44 longer.
• Horta et al. (Am J Epidemiol 19971461128-1133)
  smoking not associated with BF initiation but
  associated with BF duration.

3
Background

• Maternal smoking before, during or after
  pregnancy?
• PRAMS
• sample size
• asks about smoking before, during and after
  pregnancy

4
Methods I

• Oregon PRAMS
• Stratified random sample of Oregon resident
  mothers
• Year 1 babies born 8/1/98-8/9/99.
• Weighted for oversampling, nonresponse and
  noncoverage.
• Duration of breastfeeding
• "For how many weeks did you breast-feed your
  new baby?"
• Over 99 completed after baby 10 weeks old.

5
Methods II

• PRAMS
• Smoking before, during and after pregnancy.
• Before in the 3 months before pregnancy
• During in the last 3 months of pregnancy
• After smoking now (10-26 weeks after birth)

6
Results I

• Response rate 1867/2919 64.0
• 83.6 of women initiated breastfeeding.
• 59.5 of women were still breastfeeding at 10
  weeks old.

7
Results II

• Strength of Association Between Time of Maternal
  Smoking and Not Breastfeeding at 10 Weeks
  (multivariate)
• Time of Smoking ORa
  95 CI
• Before Pregnancy
• Smokers
  2.17 1.47, 3.23
• During Pregnancy
• Smokers
  1.85 1.11, 3.13
• After Pregnancy
• Smokers
  2.56 1.64, 4.00
• For all 3 times reference is non-smokers
• Before in the 3 months before pregnancy
• During in the last 3 months of pregnancy
• After smoking now (10-26 weeks after birth)

8
Conclusions

• Maternal smoking associated with decreased
  breastfeeding
• Parallel work Letson GW, Rosenberg KD and Wu L.
  Association between smoking during pregnancy and
  breastfeeding at about two weeks of age in
  Oregon, 1998. Journal of Human Lactation.
  200218368-372
• Maternal exposure to nicotine decreases breast
  milk output.
• Smoking mothers may have lower milk output and
  lower prolactin levels than nonsmoking mothers

9
Public Health Implications

• Assist pregnant women who wish to stop smoking
• Helping mothers to quit smoking should increase
  breastfeeding duration
• Breastfeeding support programs