Arezoo Heydari - midwifery Faculty of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Nourossadat Kariman - Assistant professor of Department of Midwifery and Reproductive Health, Faculty Of Nursing And Midwifery,Shahid Beheshti University Of Medical Sciences, Tehran, Iran
Zahra Naeeji - Mahdie hospital, Department of OB&GYN Shahid Beheshti University of Medical Sciences, Tehran, Iran
Farzaneh Ahmadi - Faculty of Paramedicine Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Background and Aim : Magnesium sulfate is an anti-seizure medication that has many other uses in themidwifery, including the manufacture of osmotic dilators that are used to cervical ripening. Its mainmechanism of action is to reduce the amount of intracellular calcium through its magnesium component.Also, due to hyperosmolarity, this solution can also be effective in absorbing intercostal water and reducingedema. With these two mechanisms mentioned, it can be effective in improving effacement and dilatationof the cervix (10-15% of the cervix contain from smooth muscle). The present study was conducted todetermine the effect of hyper-osmolar magnesium sulfate solution on labor prosses.Methods : 64 nulliparous women with term pregnancy were examined in this clinical trial . Participantswere evaluated in two groups of 32. In the intervention group, at the beginning of the active phase, 10 ccmagnesium sulfate 50% and in the control group 10 cc distilled water was poured on the cervix and thenthe labor prosses was examined in two groups. Data were analyzed using SPSS software.Results : In the intervention group, the mean active phase duration was 1.13 ± 1.75 hours and in the controlgroup was 1.87 ± 3.85, which was 2.10 hours longer than the magnesium sulfate group (p = 0.001). Therewere no significant differences between the two groups in terms of the mean score of Apgar, deliverychannel lacerations and other complications. The number of natural births was higher in the magnesiumsulfate group, but this difference was not significantConclusion : The results of the study showed that the use of topical magnesium sulfate in the active phaseimproves effacement and dilatation and shortens duration of labor. Due to the limited studies in this field,further studies are recommended

Magnesium Sulfate, effasement, dillation, primiparpus