Medication Summary
No medication is of specific benefit to a patient with placenta previa. Tocolysis may be cautiously considered in some circumstances. Encourage patients with known placenta previa to maintain intake of iron and folate as a safety margin in the event of bleeding.
Tocolytics
Class Summary
Prevent preterm labor or contractions.
Magnesium sulfate
Nutritional supplement in hyperalimentation; cofactor in enzyme systems involved in neurochemical transmission and muscular excitability. In adults, 60-180 mEq of potassium, 10-30 mEq of magnesium, and 10-40 mEq of phosphate per day may be necessary for optimum metabolic response. Administer IV or IM for seizure prophylaxis in preeclampsia. Use IV route for quicker onset of action in true eclampsia. Discontinue treatment as soon as desired effect is obtained. Repeat doses dependent on continuing presence of patellar reflex and adequate respiratory function.
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| Morbidities | Relative Risk |
| Antepartum bleeding | 10 |
| Need for hysterectomy | 33 |
| Blood transfusion | 10 |
| Septicemia | 5.5 |
| Thrombophlebitis | 5 |
| Endometritis | 6.6[1] |

