Many factors are observed to influence the IUD insertion process. This study sought to examine the effects of a few key variables on IUD insertion tolerability, complications, and follow-up issues.

A retrospective chart review was undertaken of all IUD insertions over an 11-month period at an urban Canadian women’s clinic. Linear regression analysis of 354 insertions assessed the effects of parity, age, local anesthesia, and other variables on insertion pain. A χ2 test was performed to compare follow-up expulsion or removal rates by parity.

Statistically significant differences were found, with nulliparous women and those who received local anesthesia reporting more insertion pain. Age, IUD type, and recent abortion status did not affect insertion pain. Nulliparous women did not experience significantly more insertion difficulty or complications, nor did they have higher rates of expulsion or removal at follow-up.

The study concluded that the practice of providing cervical anesthesia at IUD insertion may cause slightly more pain, without any obvious additional benefit. The difference in insertion pain by parity, is small enough to be of questionable clinical importance. Overall, these findings add to the growing body of evidence for IUDs being safe and well-tolerated in nulliparous women.