Format

Send to

Choose Destination
Thyroid. 2014 Oct;24(10):1533-40. doi: 10.1089/thy.2014.0150. Epub 2014 Jun 25.

Severity of birth defects after propylthiouracil exposure in early pregnancy.

Author information

1
1 Department of Endocrinology, Aalborg University Hospital , Aalborg, Denmark .

Abstract

BACKGROUND:

Propylthiouracil (PTU) used in the treatment of maternal hyperthyroidism in early pregnancy may be associated with a higher prevalence of birth defects in the face and neck region and in the urinary system but the severity of these complications remains to be elucidated.

METHODS:

Review of hospital-registered cases of birth defects in the face and neck region and in the urinary system after PTU exposure in early pregnancy. We obtained information on maternal redeemed prescription of PTU and child diagnosis of birth defect from nationwide registers for all children born in Denmark between 1996 and 2008 (n=817,093). The children were followed until December 31, 2010 (median age, 8.3 years) and the Cox proportional hazards model was used to estimate adjusted hazard ratio (HR) with 95% confidence interval (CI) for having a birth defect after PTU exposure versus nonexposed children (n=811,730).

RESULTS:

Fourteen cases of birth defects were identified in the face and neck region and in the urinary system after PTU exposure in early pregnancy; 11 children were exposed to PTU only (n=564), whereas 3 children were born to mothers who switched from methimazole (MMI)/carbimazole (CMZ) to PTU in early pregnancy (n=159). Among children exposed to PTU only, the adjusted HR for having a birth defect in the face and neck region was 4.92 (95% CI 2.04-11.86) and in the urinary system 2.73 (1.22-6.07). Looking into details of the 14 cases, 7 children were diagnosed with a birth defect in the face and neck region (preauricular and branchial sinus/fistula/cyst) and 7 children had a birth defect in the urinary system (single cyst of kidney and hydronephrosis). Surgical treatment was registered in 6 of the cases with a birth defect in the face and neck region and 3 of the cases with a birth defect in the urinary system. Two of the children with a birth defect in the urinary system also had other birth defects (genital organs).

CONCLUSIONS:

We report details on possible PTU-associated birth defects. They tend to be less severe than the defects observed after MMI/CMZ exposure. Yet, the majority of affected children had to undergo surgery.

PMID:
24963758
PMCID:
PMC4195247
DOI:
10.1089/thy.2014.0150
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Atypon Icon for PubMed Central
Loading ...
Support Center