You are leaving Medscape Education
Cancel Continue
Log in to save activities Your saved activities will show here so that you can easily access them whenever you're ready. Log in here CME & Education Log in to keep track of your credits.
 

CME

Smoking Reduces Iodine Transport Into Breast Milk

  • Authors:
  • CME Released: 1/23/2004
  • THIS ACTIVITY HAS EXPIRED
  • Valid for credit through: 1/23/2005
Start Activity


Target Audience and Goal Statement

This article is intended for primary care physicians, obstetricians and gynecologists, and other specialists who care for lactating women or their infants.

The goal of this activity is to provide the latest medical news to physicians and other healthcare professionals in order to enhance patient care.

Upon completion of this activity, participants will be able to:

  • Describe the effect of smoking on iodine metabolism of lactating mothers and their breastfeeding infants.
  • Assess the risk of iodine deficiency in infants of smoking mothers.


Disclosures

As an organization accredited by the ACCME, Medscape requires authors and editors to disclose any significant financial relationship during the past 12 months with the manufacturer of any product that may relate to the subject matter of the educational activity, whether or not the activity is commercially supported. Authors are also asked to disclose any mention of investigational products or unapproved uses of products regulated by the U.S. Food and Drug Administration.


Author(s)

  • Laurie Barclay, MD

    Laurie Barclay is a freelance reviewer and writer for Medscape.

    Disclosures

    Disclosure: Dr. Barclay has reported no significant financial interests.

CME Authors

  • Désirée Lie, MD, MSEd

    Clinical Professor, Family Medicine, University of California, Orange; Director, Division of Faculty Development, UCI Medical Center, Orange, California

    Disclosures

    Disclosure: Dr. Lie has reported no significant financial interests.


Accreditation Statements

    For Physicians

  • Medscape, LLC is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.

    Medscape designates this educational activity for 0.25 category 1 credit(s) toward the AMA Physician's Recognition Award. Each physician should claim only those credits that reflect the time he/she actually spent in the activity.

    Contact This Provider

For questions regarding the content of this activity, contact the accredited provider for this CME/CE activity noted above. For technical assistance, contact [email protected]


Instructions for Participation and Credit

There are no fees for participating in or receiving credit for this online educational activity. For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board.

This activity is designed to be completed within the time designated on the title page; physicians should claim only those credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the activity online during the valid credit period that is noted on the title page.

Follow these steps to earn CME/CE credit*:

  1. Read the target audience, learning objectives, and author disclosures.
  2. Study the educational content online or printed out.
  3. Online, choose the best answer to each test question. To receive a certificate, you must receive a passing score as designated at the top of the test. Medscape encourages you to complete the Activity Evaluation to provide feedback for future programming.

You may now view or print the certificate from your CME/CE Tracker. You may print the certificate but you cannot alter it. Credits will be tallied in your CME/CE Tracker and archived for 5 years; at any point within this time period you can print out the tally as well as the certificates by accessing "Edit Your Profile" at the top of your Medscape homepage.

*The credit that you receive is based on your user profile.

CME

Smoking Reduces Iodine Transport Into Breast Milk

THIS ACTIVITY HAS EXPIRED

CME Released: 1/23/2004

Valid for credit through: 1/23/2005

processing....

Jan. 23, 2004 — Smoking reduces the transport of iodine into breast milk, according to the results of a study published in the January issue of the Journal of Clinical Endocrinology and Metabolism. The investigators suggest that women who breastfeed should not smoke, but if they do, they should have iodine supplementation.

"Lack of iodine for thyroid hormone formation during the fetal stage and/or the first years of life may lead to developmental brain damage," write Peter Laurberg, from Aalborg Hospital in Denmark, and colleagues. "During the period of breastfeeding, thyroid function of the infant depends on iodine in maternal milk."

The investigators used cotinine levels in urine and serum to identify whether healthy pregnant women who were admitted for delivery were smokers (n = 50) or nonsmokers (n = 90). Both groups had identical urinary iodine on the fifth postpartum day, but smoking was associated with reduced iodine content in breast milk (26.0 µg/L vs. 53.8 µg/L; P < .001) and in the infants' urine (33.3 µg/L vs. 50.4 µg/L; P = .005).

Multivariate linear models and logistic regression analysis revealed that the odds ratio for smoking vs. nonsmoking mothers to have lower iodine content in breast milk than urinary iodine content was 8.4 (95% confidence interval, 3.5 - 20.1). In smokers, iodine transfer into breast milk was inversely related to urinary cotinine concentration. Smoking mothers had significantly higher serum levels of thiocyanate, which may interfere with iodide transport in the lactating mammary gland by competitive inhibition of the sodium-iodide symporter.

"Smoking during the period of breastfeeding increases the risk of iodine deficiency-induced brain damage in the child," the authors write. "Women who breastfeed should not smoke, but if they do, an extra iodine supplement should be considered."

J Clin Endocrinol Metab. 2004;89:181-187

  • Print