Which among the following is the most common side effect of IUD inseion?

The most common side effects repoed by IUD users are cramping and bleeding. These symptoms can be minimized with the use of a nonsteroidal anti-inflammatory drug. However, if symptoms are persistent or severe the patient should be evaluated for infection or perforation. Other side effects are dysmenorrhea, expulsion, or uterine perforation. Ref: Brunsell S.C. (2011). Chapter 17. Contraception. In J.E. South-Paul, S.C. Matheny, E.L. Lewis (Eds), CURRENT Diagnosis & Treatment in Family Medicine, 3e.