The use of cellular (mobile) phone has been exploded world wide dur- ing last decade. Their rapid adoption by general public has resulted in an increased research interest in possible harmful health effectsllahavanai- n'en et aL. 2004. This common use of cellular phones has given rise to concerns about the potential influences of electromagnetic fields on hu- man physiology (Croft et al., 2002). We the effect of electromagnetic jields emitted by cellular phone on fetal heart rate patterns, end diastolic volume. end systolic vol- ume . stroke volume and cardiac output. Our results showed that after use of mobile phones on different gestational ages (group I. [I & III). significant increase in FHR and significant reduction of EDV.‘ ESV. SV & Cop. The percent of reduc- tion in EDV was more than the percent of reduction in ESV in all groups. This prominent decrease in EDV more than the decrease in ESV suggests that the decrease in SV is mainly due to decrease in contractility. We conclude that the use of mobile phone has a negative effect on fetal heart so we recommend avoidance of cellular phone use especially in the early weeks of gestation and if necessary. the phone call should be less than ten minutes.