38.107.191.113
MedPix® Medical Image DatabaseDisease Topic 2581
(Reviewed and Approved) :: Link to this Topic
Click Here for MedPix®-2
» » - - Print Topic - - « «
Contributor: Stephanie Bernard
Scroll to Bottom to Display Images (if available)
More Like This ? Twin Gestation
Factoid 2581 - Created: 2001-07-24 23:31:49-04 - Modified: 2004-06-08 19:31:53-04
ACR Codes: 8.1
Twin gestations make up approximately 1-2% of all pregnancies and are associated with a significant increase in morbidity and mortality for both the mother and the fetuses. Addtional characteristics of a twin gestation that alter the expected outcome for the fetusesare the chorionicity (number of placentas)and amnionicity (membranes). The perinatal mortality rates are approximately 10% in dichorionic, 25% in monochorionic,diamniotic and 50% in monochorionic,monoamniotic gestations. Identification is therefore important for planning prenatal surveillance as well as for counselling of the parents. Early, chorionicity can be determined by counting gestational sacs and amnionicity by counting the number of embryos within a single sac by assessing heart activity. Around 10 weeks, the placentas and membranes fuse making this assessment more difficult. As dichorionic pregnancies have a membrane composed of 2 layers of amnion and two layers of chorion, the intervening membrane is thicker than seen with a monochorionic, diamnionic pregnancy but this becomes less appearant later in pregnancy. If the placentas are not identifiable as seperate, a finding which indicates a dichorionic (or multichorionicity in multiple gestation) pregnancy is the extension of a triangular projection of the placenta between the membranes. This finding, referred to as the "twin peak sign" is not seen in monochorionic pregnancies.
Display Images - || - Image Slide Sorter
Location:
Genitourinary 		Sublocation:
Uterus		Category:
Anatomy, Normal Variant
More Like This ? - Find Related Topics: Click on the Location, Sublocation, or Category Links Above
Send this Search to ... More Like This ?  - - CHORUS - - Google™
Written by: Stephanie Bernard
Prepared by: Stephanie A Bernard
Affiliation: Penn State University - || - Author Profile
Approved by: James G. Smirniotopoulos, M.D.
Affiliation: Uniformed Services University - || - Editor Profile
-


Use this MedPix® Visitor Feedback Form for Comments and Suggestions

MedPix® is sponsored by the Department of Radiology and Radiological Sciences, USUHS, Bethesda, MD
We do not accept paid advertisements.

This website is accredited by Health On the Net Foundation. Click to verify. We comply with the HONcode standard
for trustworthy health information:
verify here.

Text and Images may be Copyrighted © 1999 - 2009 by the Original Content Contributors.
Copyrighted materials are reproduced here with their Permission.
MedPix® is a Registered Trademark of USUHS :: The MedPix® Database Engine is Patented - USPTO No. 7,080,098
Portions of MedPix® are Copyright © 1999 - 2009 by J.G. Smirniotopoulos, M.D. & H. Irvine, M.D.
The MedPix® Classification Schema Copyright © 1999 - 2009 by J.G.Smirniotopoulos,M.D.
MedPix® has displayed more than   266,900,044   pages since 3 September 2000.
Database Successfully Disconnected