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Effects of maternal left lateral position and rest on amniotic fluid index: a prospective clinical study
Kahraman Ulker1, Ismail Temur, Mehmet Karaca
1Department of Obstetrics and Gynecology, Kafkas University School of Medicine, Kars, Turkey. kahramanulker@hotmail.com
Objective:
To compare the effect of both maternal rest and activity on the amniotic fluid index (AFI).
Study Design:
Power analysis indicated that in order to achieve 20 mm of increase in AFI with 90% of power at one side alpha of 0.01, we needed at least 51 women in each group. The study group was comprised of pregnant women (n = 152) with a normal AFI and a singleton pregnancy at 26-40 weeks' gestation. Their AFI was determined by averaging the 2 repetitive measurements of the 4 amniotic fluid quadrants. The "rest" group (n = 77) was instructed to lie and rest in the left lateral position, and the "mild activity" group (n = 75) was instructed to sit and walk.
Results:
AFI increased significantly, from 151.25 +/- 37.40 mm to 173.79 +/- 39.76 mm, in the "rest" group (p = 0.00). However, the change from 153.69 +/- 37.94 to 152.34 +/- 36.62 mm was not significant in the "mild activity" group (p = 0.167).
Conclusion:
Maternal rest in the left lateral position increases the AFI.
