It is a well-known paradigm that the more the film is oriented, the worse it has tear resistance through one direction and the use of fillers such as CaCO3 has further negative effect. Machine direction orientation (MDO) process is vital for high breathability and downgauging of hygiene films while it sharply reduces tear resistance. Tear strength is crucial for sanitary napkin backsheet films from an application point of view. This paper outlines the effects of ethylene based elastomers on machine direction tear resistance in the case of MDO processed breathable polyethylene hygiene films. Additionally, an application based test method was developed for film characterization since such breathable films give almost no result when they are tested by conventional tear strength test equipment. Besides that, dart drop impact and stiffness tests have been performed to come up with some correlation to estimate the tear strength on the final product. Our results show that ethylene based elastomers can be used to provide better tear performance and the following parameters should be optimized; thickness, CaCO3 content, MDO parameters, polymer matrix, and dosing ratio of some functional additives. Keywords: Breathable hygiene films, elastomer, polyethylene, MDO process, blown film. Acknowledgments This study has been financially supported by HAYAT KİMYA A.Ş. REFERENCES 1. Lee, L. W., Register, R. A., Dean, D. M., Journal of Polymer Science, Part B: Polymer Physics, 43, 413, 2005. 2. Lee, L. W., Register, R. A., Dean, D. M., Journal of Polymer Science: Part B: Polymer Physics, Vol. 43, 97, 2005. 3. Godshall, D., Wilkes, G., Krishnaswamy, R. K., Sukhadia, A. M., Polymer, 44, 5397, 2003. 4. Breese, D. R., Beaucage, G., Current Opinion in Solid State and Materials Science, 8, 439, 2005.