 In pregnancy, it is more useful during the second and third trimester, particularly as the enlargening uterus displaces the appendix, making it difficult to find by ultrasound.The periappendiceal stranding that is reflected on CT by fat stranding on MRI appears as an increased fluid signal on T2 weighted sequences.First trimester pregnancies are usually not candidates for MRI, as the fetus is still undergoing organogenesis, and there are no long-term studies to date regarding its potential risks or side effects.