Serum-Mediane von Placentaprotein-Markern: Relevanz der Unterschiede zwischen spontanen und nach-in-vitro-Fertilisation eingetretenen Schwangerschaften für das fetale Trisomie-Screening.

Trisomy-21 (Down syndrome) is the most frequent chromosomal abnorm- ality but only one third of cases would be detected by amniocentesis based on maternal age alone. Serum screening tests in the early second trimester increase the detec- tion rate to 60-65%, and more recently it was found that such screening was also possible in the first trimester by quantifying a diffe- rent panel of markers. The concen- trations of these placental proteins are strongly dependent on gestatio- nal age; thus control medians must be established and precise dating is essential. Serum chorionic gonado- trophin (HCG) levels were recently found to be increased in IVF preg- nancies compared to spontaneous gestations, leading to a falsely ele- vated trisomy screening risk. The aim of this preliminary study was to find out whether, in the first-trime- ster screening, the markers similarly differed between IVF and spontane- ous pregnancies which would call for the establishment of separate normal medians for IVF patients. We compared 24 pregnancies ob- tained after ovarian stimulation and IVF with six women after thawed embryo transfer (unstimulated cycle) and 63 gestation- and maternal-age matched spontaneously pregnant controls. A single serum was ob- tained between 6 and 16 weeks of gestation and various placental protein levels determined by im- munometric assays. Serum levels of pregnancy-associated plasma protein A (PAPP-A), which is the major marker in the first-trimes- ter screening test, were reduced in IVF pregnancies: after 9 weeks of gestation, multiples of median (MoMs) ranged between 0.23 and 3.58 (logarithmic mean 0.743). For the frozen/thawed transfers, this value was 1.08. In the 9-12 week group containing 6 cases of IVF, three thawed transfers and 25 con- trols, PAPP-A was significantly redu- ced in the stimulated compared to the nonstimulated cycles. In the late first and early second trimester the difference was not significant in our small group but the trend persisted. Pregnancies after IVF will thus show an increased incidence of false positive results in fetal trisomy-21 screening, and special medians should be established for these pati- ents.

Die Konstruktion einer medizinischen Disziplin und ihre Herausforderungen: die Orthopädie in der Schweiz im 19. und 20. Jahrhundert [The construction of a medical discipline and its challenges: Orthopedics in Switzerland during the 19th and 20th centuries].

(ENGLISH VERSION BELOW) Dieser Beitrag fügt sich in eine post-doktorale Forschung über die Geschichte der Orthopädie ein, die unter dem Mandat des Centre Hospitalier Universitaire Vaudois (CHUV) geleitet wird und teilerweise auf die Archiv der Schweizerischen Gesellschaft für Orthopädie (aktuelle Swiss Orthopaedics) beruht. Die Autorin untersucht die Herausforderungen, welche die Geschichte der Orthopädie in der Schweiz prägten und berücksichtigt dabei die Anpassungsstrategien einer medizinischen und technischen Disziplin in einer sich wandelnden Gesellschaft. Zusammenfassung der Beitrag und Informationen auf der Website der Zeitschrift: http://econtent.hogrefe.com/toc/tum/72/7 This article is inspired by a post-doctorale research about the history of orthopedics, mandated by the Centre Hospitalier Universitaire Vaudois (CHUV), and partly supported by the Archiv of the Swiss Society of Orthopedics (nowadays Swiss Orthopaedics). By examining the implications that have shaped the history of orthopedics in Switzerland, the author seeks to shed light on the strategies that were implemented in adopting a medical and technical discipline within a transforming society. Summary of the article and information on the journal's website: http://econtent.hogrefe.com/toc/tum/72/7