Conference Thyroid Function and Conception 13.8.1398
Thyroid Function and Conception
CLINICAL DECISIONS
The NEW ENGLAND JOURNAL of MEDICINE
A Woman Trying to Conceive
Mrs. Thompson is a 31 y/o woman who has been trying to conceive for the past 12 months and comes to see you, her primary care physician. One month ago, she had a miscarriage at 7 weeks of gestation.
She has not had any other pregnancies. Ms. Thompson has always been healthy; she has no significant medical history. Her only regular medication is a prenatal multivitamin, which she has been taking regularly for the past 12 months.
Before that, she had used the combined estrogen–progesterone oral contraceptive pill for several years. Since she discontinued the contraceptive pill, her menses have been regular, with a 28-day cycle.
Her family history is significant for autoimmune disease. Her brother has type 1 diabetes mellitus, and a maternal uncle has Hashimoto’s thyroiditis.
Mrs. Thompson has no personal history of thyroid disease and reports no symptoms suggestive of hyperthyroidism or hypothyroidism, nor does she have any localized neck discomfort or swelling.
TSH: 3.2 mIU /l (0.5 to 4.0)
free T4: 1.1 ng /dl (0.86 to 1.9 )
thyroid peroxidase antibodies is positive (78 IU/ml [normal <35])
Ms. Thompson has read that changes in thyroid function can affect a woman’s chances of having a successful pregnancy.
Given the results of her tests, she is interested in your recommendation as to whether she should begin treatment with levothyroxine to increase her chances of conceiving.