Pregnancy: Physiologic Changes and Considerations for Dental Patients

By Dellinger TM, Livingston HM.

Date: 04/2006
Journal: Dent Clin North Am


•Pregnancy is a dynamic physiological state evidenced by several transient changes.

•The most common complaints include nausea and vomiting, nasal congestion, heartburn, alteration in taste and food cravings, hyperventilation, shortness of breath, and fatigue.

•Physiologic changes during pregnancy:

  • Increase oxygen demand. The liver has increased hepatic production of hormone-binding globulins and decreased albumin, resulting in significant impact on the pharmacokinetics.
  • There is a 40% to 50% increase in total blood volume, iron supplements are often recommended
  • Many coagulation factors are increased result in a hypercoagulable state.
  • No change in systemic arterial pressure during normal gestation, a slight decrease in diastolic during midpregnancy.
  • Increases in weight result in a strain on the intervertebral disks, leading to generalized back pain.
  • Gestational diabetes mellitus (GDM) is found in approximately 4% of cases. 4 kg or higher birth weights.
  • Pregnant women may be more susceptible than other women to infection
  • physiological effects 
  • alterations in pharmacokinetics


  • FDA has developed a 5-category system to determine fetal risks of medications. Most fetal organogenesis occurs during the first trimester.
  • Not all drugs readily pass through the placental barrier. Drugs that would readily cross include lipid-binding drugs, acidic medications, or those depend on renal clearance.
  • Tetracycline and minocycline are associated with abnormalities in bone and dental development. These drugs are thus not advised for pregnant patients.
  • Fortunately, many drugs in a dental office’s armamentarium are considered generally safe for both pregnant patients and their unborn children.
  • Lidocaine and prilocaine should be first-line choices for local anesthesia for pregnant women who do not have any contraindication. Additionally, the use of vasoconstrictors, such as epinephrine or levonorderfrin, is not contraindicated when used at or below therapeutic ranges.
  • First line antibiotics are rated by the FDA as category B for pregnancy risk. These include the penicillin family, the erythromycins (except for the estolate form), azithromycin, clindamycin, metronidazole, and the cephalosporins.
  • Fungal infections may be treated with nystatin.
  • Not all nonsteroidal anti-inflammatory drugs are safe for the fetus. Neither aspirin nor diflusinal are recommended for a pregnant woman.
  • Ibuprofen is contraindicated in the third trimester of pregnancy, where it is considered FDA category D choices, due to their risks of prolonged labor, hemorrhage during delivery. However, it is given a category B rating for the first two trimesters.
  • the first-line nonsteroidal anti-inflammatory of choice should be acetaminophen.

•Dental treatment during pregnancy:

  • Dental procedures that minimize mother’s oral bacterial load are beneficial for her fetus.
  • Dental hygiene procedures, such as prophylaxis, deep scaling, or root planning are allowable in any trimester of a normal pregnancy
  • If dental caries is a source of pain or acute infection in an otherwise healthy gestational woman, a dentist should provide invasive care no matter what the phase of pregnancy
  • there is no contraindication to using diagnostic procedures deemed necessary, such as appropriate radiographs, during a patient’s pregnancy, as long as normal safety precautions are followed.