Introduction. Assessment of the fetal heart rate become a routine manner and was found to be helpful in making important clinical decisions. In the available literature there are no any information about fetal heart rate in twin pregnancy and it usefulness in predicting pregnancy outcome.
Objective. The aim of our study was to evaluate a range of heart rates in the first trimester in twin pregnancy and the influence of the rate of fetal heart on the outcome of the pregnancy.
Material and methods. The study included 89 twin pregnancies between 6 and 11 weeks of pregnancy (78 pregnancies finished with good outcome and 11 with unfavorable outcome).
Results. The date shows that the heart rate of embryos / fetuses in the first trimester of an uncomplicated twin pregnancy progressively increases between 6 and 8 weeks of pregnancy and then slows down in week 11. Our data shows that the rate of fetal death in the first trimester of twin pregnancy increases progressively with decreasing of the heart rate. In our study none of the twins survived when the observed rate of the fetal heart was less than 110 beats per minute and half of them died when heart rate was between 110 and 120 beats per min. Furthermore, the significant difference in the heart rates of a set of twins was connected with a poor prognosis. In monochorionic pregnancies with a significant difference in heart rate (20 beats/min or more) despite a normal fetal heart rate (120 beats/min or more) TTTS syndrome was confirmed later in pregnancy.
Conclusions. The heart rate in twin pregnancy more than 120 beats per minute is connected with a good prognosis, whereas below 110 beats per minute with a poor prognosis. Furthermore, the significant difference in fetal heart rate (20 beats/min or more) can be a marker of developing TTTS syndrome later in pregnancy.