The electrocardiogram of pregnant Nigerian women.

Data from standard electrocardiographic recording in 41 pregnant Southern Nigerian women and in 39 non-pregnant controls of similar ages are given. The results show a mean of 12 degrees axis deviation between the pregnant and non-pregnant subjects, with mean values of 44 +/- 23.00 degrees and 56 +/- 11.00 degrees respectively. Compared to the results in Caucasians, there was greater QRS axis deviation from the 1TM to the 3TM in Africans. Mean heart rate of the Nigerian subjects was lower than that reported for the Caucasians, although it was higher than that of the non-pregnant controls. The durations and amplitudes of the different waves and intervals were greater in the non-pregnant subjects. These values also varied between Caucasians and Africans. The occurrence of the S1Q3T3 pattern was observed; with Q3 and T3 increasing significantly (P < 0.05) in the 3TM. A greater significant (P < 0.05) difference in the occurrence of the T3 pattern was observed between the pregnant and the non-pregnant subjects, showing that the T3 is the most prominent ECG change during pregnancy.