[Effect of amniotomy in latent and active phases on rate of cesarean section]

Increase in number of cesarean sections has caused some alarming advices by clear-sighted authorities. So, it is necessary to study the factors affecting the rate of cesarean sections. To compare the effect of amniotomy on mode of delivery in both active and latent phases. This was an analytical cohort study carried out at Kosar hospital, Qazvin [Iran] in 2003-2004. The study population consisted of all admitted women [n=305] whose labor was induced by amniotomy. The patients were further divided into two groups marked as study group [n=174] and comparison group [n=131] based on being in latent phase or active phase, respectively. Statistical analyses was performed using t-test, chi-square, and Mann-Whitney tests. Cesarean section was significantly higher [p=0.001] in study group than in comparison group, 19 [10.9%] vs. 2 [1.5%]. Non-progressive labor during the first stage of labor showed to be considerably higher in study group [p=0.001]. Also non-progressive labor during the second stage was [2.9%] in study group [1.5%] in comparison group with no statically significant difference. Abnormal fetal heart rate patterns showed no significant difference, statistically. Oxytocin administration in study group was [43.7%] and in comparison group [4.6%] showing statically a significant difference [p=0.000]. Regarding our data, cesarean section, none progressive labor during the first stage, and oxytocin administration were all higher in latent phase group than in active phase group. It sees that early amniotomy may increase the need for cesarean section