OBJECTIVES: Uterine myomas may change the concentrations of the screening serum 
markers and therefore alter the risk calculation of the fetal chromosomal 
abnormalities. An increased risk leads to invasive diagnostics procedures which 
in these cases can often be technically difficult due to the presence of myomas.
AIM: The aim of this study was to assess the influence of uterine myomas on the 
first and second trimester serum markers concentrations and, possibly on the 
test results.
MATERIAL AND METHODS: The study group consisted of 127 women between 11 and 20 
weeks of normal singleton pregnancy. In each case uterine myomas were 
diagnosed--over 20 mm in the diameter and located in the uterine wall. 77 
patients underwent the first trimester screening (PAPP-A & free beta-hCG) and 50 
patients had the second trimester screening (triple test). The control group 
consisted of 1020 women between 11 and 20 weeks of normal singleton pregnancy 
without uterine myomas. Delfia Xpress analyser was used for the serum markers 
estimations. All pregnant women delivered normal healthy babies.
RESULTS: In the first trimester group the PAPP-A serum concentrations were not 
different from the controls while the mean median concentration of free beta-hCG 
were significant higher--1.43 MoM. In the second trimester group the following 
mean median values were observed: no significance for the AFP--1.18 MoM and 
estriol--1.29 MoM and significantly higher mean median value for the free 
beta-hCG--2.01 MoM.
CONCLUSIONS: 1. The presence of the uterine myomas is connected with the 
increased maternal serum concentration of the beta-hCG, particularly in the 
second trimester. 2. The uterine myomas may lead to the increased rate of the 
false positive results of the prenatal screening test, especially the triple 
test.