title: Comparison of intrauterine hematologic and biochemical values between twin pairs with and without stuck twin syndrome.
abstract: OBJECTIVE
  Our purpose was to compare hematologic and biochemical values in cordocentesis specimens from twin pairs with and without stuck twin syndrome.
  
  
  METHODS
  Cordocentesis was performed on 38 twin pairs. Assignment to the stuck twin syndrome group (n = 8) was based on ultrasonographic findings of discordant size and amniotic fluid volume, concordant gender, and a single placenta. A receiver-operator characteristic curve was constructed with the use of intertwin hemoglobin differences. For the stuck twin syndrome group regression analysis of gestational age and intertwin hemoglobin difference was done.
  
  
  RESULTS
  We found significant (p = 0.03) intertwin differences in hemoglobin between the stuck twin syndrome group (mean 5.35 gm/dl, range 0.5 to 15.4 gm/dl) and the comparison group (mean 0.10 gm/dl, range 0.0 to 2.4 gm/dl). A nearly significant relationship between gestational age and intertwin hemoglobin difference was noted in the stuck twin syndrome group. When the hemoglobin difference was > 2.4 gm/dl, all cases had stuck twin syndrome (sensitivity = 50%, specificity = 100%, positive predictive value = 100%, negative predictive value = 91%). In the stuck twin syndrome group there was a trend toward larger intertwin differences in albumin and total protein. Intertwin blood gas values between the groups did not differ, but the average PO2 was lower when the smaller twins of the two groups were compared.
  
  
  CONCLUSIONS
  An intertwin difference in hemoglobin > 2.4 gm/dl is consistent with stuck twin syndrome. Large intertwin hemoglobin differences and imbalances in albumin and total protein may be seen in stuck twin syndrome.
authors.affiliation: Department of Obstetrics and Gynecology, Wayne State University/Hutzel Hospital, Detroit, MI 48201, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Berry
authors.forename: K S
authors.initials: KS
authors.lastname: Puder
authors.forename: S F
authors.initials: SF
authors.lastname: Bottoms
authors.forename: J E
authors.initials: JE
authors.lastname: Uckele
authors.forename: R
authors.initials: R
authors.lastname: Romero
authors.forename: D B
authors.initials: DB
authors.lastname: Cotton
mesh_terms: D001774:Blood Chemical Analysis; D001798:Blood Proteins / Q000378:metabolism; D017218:Cordocentesis; D005189:False Positive Reactions; D005260:Female; D005315:Fetal Diseases / Q000097:blood*; D005330:Fetofetal Transfusion / Q000097:blood*; D005333:Fetus / Q000378:metabolism*; D005865:Gestational Age; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D010100:Oxygen / Q000097:blood; D011237:Predictive Value of Tests; D011247:Pregnancy; D012372:ROC Curve; D012044:Regression Analysis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012709:Serum Albumin / Q000378:metabolism; D013577:Syndrome; D014427:Twins
chemical_list: D001798:Blood Proteins; D006454:Hemoglobins; D012709:Serum Albumin; D010100:Oxygen