It's a myth that calcium is lost from the mother's teeth and "one tooth is lost with every pregnancy."  But you may experience some changes in your oral health during pregnancy.  The primary change is a surge in hormones - particularly an increase in estrogen and progesterone - which is linked to an increase in the amount of plaque on your teeth.  If you're planning to become pregnant or suspect you're pregnant, you should see a dentist right away.  Otherwise, you should schedule a check-up in your first trimester for a cleaning.  Your dentist will assess your oral condition and map out a dental plan for the rest of your pregnancy.  A visit to the dentist also is recommened in the second trimester for a cleaning, to monitor changes and to gauge the effectiveness of your hygiene.  Depending on the patient, another appointment may be scheduled early in the third trimester, but these appointments should be kept as brief as possible.