Association between uterine leiomyomas and the biochemical screening test results in the first and second trimester of pregnancy: a pilot study.

Objectives: The presence of the uterine leiomyomas may change the concentrations of the screening serum markers and so after the risk calculation of the fetal chromosomal abnormalities.

Purpose: To estimate the influence of the uterine leiomyomas on the first and second trimester serum markers concentrations.

Material And Methods: The studied group consisted of 127 women between 11 and 20 weeks of normal singleton pregnancy. In each patient, the uterine leiomyomas were diagnosed - over 20 mm in the diameter and located in the uterine wall. Seventy-seven patients had undergone the first trimester screening, 50 patients the second trimester screening. The control group consisted of 1020 women between 11 and 20 weeks of normal singleton pregnancy without uterine leiomyomas.

Results: In the first trimester group, the pregnancy-associated plasma protein A serum concentrations were not different from the controls. The median concentrations of free beta-human chorionic gonadotrophin (β-hCG) were significantly higher (1.43 MoM). In the second trimester group, no significant differences in AFP and estriol median concentrations were observed, while the median value for free β-hCG was significantly higher (2.01 MoM) than in control group.

Conclusions: The presence of the uterine leiomyomas may increase maternal serum concentration of the β-hCG and so after the rate of the false positive results of the prenatal screening tests.