Introduction:
Congenital malformations are morphological abnormalities acquired in intrauterine life and identifiable at birth.

Aim:
The aim of the analysis of outcomes of the Maternal-Fetal Medicine Centre (MFMC) practice in Olsztyn in the years 1998–2012 was to assess the efficacy of regional reference system of prenatal diagnosis.

Material and methods:
MFMC in Olsztyn performs reference non-invasive prenatal diagnosis for Warmia-Masuria Province. Patients are referred to MFCM by general gynecologists in the case of a suspected malformation or difficulty in the assessment of fetal morphology, and compulsory in the case of women above 35 years of age (NHF program). The analysis included total number of identified malformations, types of abnormalities, maternal age and gestational age at the time of diagnosis, geographic distribution in the province, number of identified malformations that were reported in national records of Polish National Registry of Fetal Cardiac Pathology.

Results and discussion:
In the material of MFMC urinary tract defects were predominant. There was a significant amount of defects in children of mothers below 35 years of age. Most defects were diagnosed in the first pregnancy. Mothers of infants with malformations more often lived in urban areas. Most defects were diagnosed in pregnant women living in Olsztyn and geographically closest counties, and the least defects were diagnosed in patients living on the eastern edge of the province.

Conclusions:
Results of the analysis confirm the significance of the presence of a facility with a profile similar to MFMC in our region. Factors that improve detection of fetal abnormalities in our region may include: extension of the NHF program to the entire population of pregnant women, improvement of first trimester diagnosis, increase of the availability of reference fetal echocardiography in pregnant women over the age of 35. Infrastructure improvement in the province may also positively affect the detection of anomalies.