Because the occurrence of a new gestation would interfere with follow-up testing of hCG levels, patients with a molar pregnancy are strong- ly advised to use reliable contraception during the entire interval of hCG monitoring. An intrauter- ine device should not be inserted before gonado- tropin remission because of the risk of perforat- ing the uterus if tumor is present. The use of either barrier methods of contraception or oral contra- ceptives should be recommended after evacuation. Although limited data have suggested that the use of oral contraceptives before gonadotropin remis- sion may be associated with an increase by a fac- tor of two to three in the frequency of tumor after a molar pregnancy, as compared with the fre- quency among women who do not use oral con- traceptives,48 a more recent randomized trial showed no increase in the risk of gestational tro- phoblastic neoplasia after molar pregnancy with the use of these contraceptives.49 Moreover, several other observational studies have likewise shown no significant association between the use of oral contraception and the risk of persistent tumor after molar pregnancy