The full content of Annals is available to subscribers

Subscribe/Learn More  >
Updates |

Update in Endocrinology

Leonard Wartofsky, MD
[+] Article, Author, and Disclosure Information

From Washington Hospital Center, Washington, DC.

Potential Financial Conflicts of Interest: None disclosed.

Requests for Single Reprints: Leonard Wartofsky, MD, Washington Hospital Center, 110 Irving Street NW, Washington, DC 20010.

Ann Intern Med. 2005;143(9):673-682. doi:10.7326/0003-4819-143-9-200511010-00011
Text Size: A A A

This Update in endocrinology represents a critical examination of articles selected from more than 25 peer-reviewed journals from the fields of endocrinology and general internal medicine. Criteria for selection included both the importance of the observations and their applicability to clinical practice today. The articles are broadly grouped into various areas of endocrinology.

First Page Preview

View Large
First page PDF preview





Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).


Submit a Comment
Increased dose of L-thyroxine in pregnancy
Posted on January 29, 2006
Michael M. Goldman
Beth Israel Medical Center, New York, NY
Conflict of Interest: None Declared

In a recent Update in Endocrinology(1), Dr. Wartofsky discusses two articles which appear to have contradictory conclusions. The first article by Anselmo et al (2), suggested that employing the model of RTH (resistance to thyroid hormone) in pregnancy, subclinical hyperthyroidism has the potential for fetal loss. The most common cause of subclinical hyperthyroidism in the U.S. is iatrogenic overdose with L-thyroxine.

The second article by Alexander et al (3) recommends an automatic 30% increase in the L-thyoxine dose of hypothyroid women in pregnancy as soon as pregnancy is confirmed. Dr. Wartofsky, himself, recommends obtaining thyroid function tests as soon as hypothyroid women become pregnant and to expect to increase their dose.

In our experience, some women require increased doses later in pregnancy and others do not require increases at all. Automatic increases in thyroid hormone can lead to subclinical hyperthyroidism in pregnancy which has the potential for fetal loss (2).

1. Wartofsky, L. Update in Endocrinology Ann Intern Med, Nov 2005; 143: 673 - 682.

2. Anselmo J, Cao D, Karrison T, et al. Fetal loss associated with excess thyroid hormone exposure. JAMA. 2004;292:691-5. [PMID: 15304465]

3. Alexander EK, Marqusee E, Lawrence J, et al. Timing and magnitude of increases in levothyroxine requirements during pregnancy in women with hypothyroidism. N Engl J Med. 2004;351:241-9. [PMID: 15254282]

Conflict of Interest:

None declared

Submit a Comment

Summary for Patients

Clinical Slide Sets

Terms of Use

The In the Clinic® slide sets are owned and copyrighted by the American College of Physicians (ACP). All text, graphics, trademarks, and other intellectual property incorporated into the slide sets remain the sole and exclusive property of the ACP. The slide sets may be used only by the person who downloads or purchases them and only for the purpose of presenting them during not-for-profit educational activities. Users may incorporate the entire slide set or selected individual slides into their own teaching presentations but may not alter the content of the slides in any way or remove the ACP copyright notice. Users may make print copies for use as hand-outs for the audience the user is personally addressing but may not otherwise reproduce or distribute the slides by any means or media, including but not limited to sending them as e-mail attachments, posting them on Internet or Intranet sites, publishing them in meeting proceedings, or making them available for sale or distribution in any unauthorized form, without the express written permission of the ACP. Unauthorized use of the In the Clinic slide sets will constitute copyright infringement.


Buy Now for $32.00

to gain full access to the content and tools.

Want to Subscribe?

Learn more about subscription options

Related Articles
Related Point of Care
Topic Collections
PubMed Articles
Forgot your password?
Enter your username and email address. We'll send you a reminder to the email address on record.