This randomized controlled trial aims to evaluate the effect of a mobile application-based support and counseling program on women in the preconception period. The study includes women aged 18 to 49 who plan to conceive within two years and meet the eligibility criteria. Participants are randomly assigned to an intervention group receiving structured preconception counseling through a mobile application or a control group receiving standard information via a booklet. The intervention consists of weekly educational modules delivered over four weeks, followed by follow-up assessments at 4 and 12 weeks. Primary outcomes include changes in preconception knowledge, attitudes, and self-efficacy. The study seeks to determine whether mobile health-based counseling enhances preconception preparedness compared with standard information.