however , iud use lasting more than 12 months was associated with a 1.5-fold increase in the crude risk of spontaneous abortion up to 28 weeks ' gestation ( p less than 0.05 ) , a 1.8-fold increased risk of first-trimester spontaneous abortion , and a 1.7-fold increased risk of incomplete abortion ( p less than 0.01 ) .
C0000786
spontaneous abortion
C0000810
incomplete abortion