First and foremost, potential topics should be whatever the Lord lays on your heart. The best articles will likely be birthed from your devotional time with Him.
Below are some suggested brainstorming ideas. You should relate with at least a few, possible several.
Mary & Martha - Health, Career, etc. - Maintaining A Walk With The Lord - Heard From The Word
Ministry - Lessons Learned - Behind The Scenes - The Pastor's Wife Perspective - Stories From The Road
Missions - On Deputation, The Field, or Furlough - Short Term Trips - Lessons Learned - The Missionary's Wife Perspective
Motherhood - Pregnancy - Through The Eyes Of My Child - Special Needs - Lessons Learned