Bleeding gums are caused by a build-up of plaque (bacteria) on the teeth. During pregnancy, hormonal changes in your body can cause the plaque to make the gums more inflamed. They may become swollen and bleed more easily. To keep your teeth and gums healthy, you should:
Pay special attention to cleaning your teeth. Ask your dentist to show you a good brushing method to remove all the plaque.
Avoid having sugary drinks and foods too often. Try to keep them only to meal times.
Discuss with you dentist whether any new or replacement filling should be delayed until after your baby is born.