Theses Florentine Thurik

On 8 December 2016 Florentine Thurik defended her thesis ‘Cell-free placental DNA beyond Down syndrome - Lessons learned from fetal RHD genotyping’ at the University of Amsterdam.

Promotors: prof CE van der Schoot MD PhD and prof A Franx MD PhD
Co-promotor: GCML Page-Christiaens PhD

The research for this thesis was conducted at the Dept of Experimental Immunohematology of Sanquin Research.

Summary

The presence of cell-free fetal DNA in maternal blood was first described in 1997 by Lo et al. These DNA fragments derive from the placenta and are therefore named cell-free placental DNA (cfpDNA) throughout the thesis. 
The first section of the thesis (chapter 2-6) discusses health care around hemolytic disease and the newborn (HDFN) and fetal and neonatal alloimmune thrombocytopenia (FNAIT), and the use of cfpDNA for fetal RHD screening for HDFN prevention are analyzed. We conclude that fetal RHD screening is a reliable method to target anti-D immunoglobulin prophylaxis to solely women who are at risk for maternal anti-D alloimmunisation. Additionally, we show that vanishings twins and a history of bone marrow transplantation could be potential causes for false-positive fetal RHD screening results. 
The second section of the thesis (chapters 7-9) focuses on the variation in cfpDNA levels and on associations between cfpDNA levels and placenta related adverse pregnancy outcomes (APOs). Associations with APOs such as preeclampsia and preterm birth are present when cfpDNA levels are measured in the third trimester, but absent when measured in the first trimester. No associations were found between first and third trimester cfpDNA levels. The results of section two combined suggest that the factors that influence cfpDNA levels in the first trimester differ from those in the third trimester.