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Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas
Published on: September 5, 2011
Maternal vasoactive exposures, amniotic bands, and terminal transverse limb defects
Martha M Werler1, Jaclyn L F Bosco, Stuart K Shapira
1Slone Epidemiology Center at Boston University, Boston, Massachusetts 02215, USA. mwerler@ slone.bu.edu
Birth Defects Research. Part A, Clinical and Molecular Teratology
|December 11, 2008
Summary
Amniotic band-limb reductions (AB-Ls) and terminal transverse limb deficiencies (TLDs) appear to be distinct conditions with different risk factors. Vasoactive exposures like smoking and aspirin are linked to AB-Ls, while decongestants and antihypertensives are associated with TLDs.
Area of Science:
- Medical research
- Epidemiology
- Teratology
Background:
- Limb reduction deficiencies (LRDs) encompass amniotic band-limb reductions (AB-Ls) and terminal transverse limb deficiencies (TLDs).
- The pathogenesis of AB-Ls and TLDs is often attributed to vascular disruption, but the role of amniotic bands as a primary or secondary factor remains unclear.
- Investigating shared risk factors could elucidate the underlying causes if amniotic bands are secondary to vascular disruption.
Purpose of the Study:
- To investigate potential shared risk factors and distinct etiologies for AB-Ls and TLDs.
- To evaluate the association between maternal demographic factors, pregnancy characteristics, and vasoactive exposures with AB-Ls and TLDs.
- To determine if specific vasoactive exposures are associated with either AB-Ls or TLDs, suggesting distinct pathogenic pathways.
Main Methods:
- A case-control study was conducted using data from the National Birth Defects Prevention Study.
- Maternal interviews provided data on 139 AB-L cases and 373 TLD cases across 10 states.
- Risk factors assessed included maternal age, education, race/ethnicity, parity, pregnancy wantedness, and periconceptional vasoactive exposures (smoking, decongestants, NSAIDs, antihypertensives).
Main Results:
- Black mothers and nulliparous mothers had increased risks for AB-Ls, while Hispanic women and those not wanting the pregnancy had increased risks for TLDs.
- Maternal smoking and aspirin use were associated with increased risk of AB-Ls, but not TLDs.
- Decongestants and possibly antihypertensive medications were associated with increased risk of TLDs, but not AB-Ls.
Conclusions:
- The distinct risk factor profiles suggest that AB-Ls and TLDs are likely separate entities.
- The findings challenge the hypothesis that these limb deficiencies share a common pathogenesis mediated by vascular disruption.
- Vasoactive exposures may not serve as universal markers for vascular disruption in the etiology of these conditions.
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