This is not in the same line with Ohlsson et al. 14
findings that showed there was no significant change
between water birth and routine care groups during
the first labor stage in primiparous women. However,
Grodzka et al. and Cluett implied that warm water
caused reduction in duration of labor stage.13,15 Malarewicz
et al. revealed that warm water had a profitable
influence which is shortening the labor stages.16
Khamis et al. studied the effect of local application of
heat on the abdominal wall on the uterine activity in
primiparous women and found that heat induced a
significant increase without causing any abdominal
fetal heart changes.7 We used dry heat therapy in our
study but we did not find a similar study, so we compare
our study with those using wet heat therapy. The
reasons for disagreement of our study results with
those of other studies can be using oxytocin in the
present study, racial differences, and warm water
immersion in other studies as compared with dry heat
therapy only in the perinea region in our study. Heat
induces blood circulation in the uterine, affecting the
force and severity of uterine muscle contraction.