Uterine fibroids increase time to pregnancy: a cohort study

Objectives: The primary purpose of the study was to investigate a possible association between uterine fibroids and time to pregnancy (TTP), and, secondly, to explore the effect of myomectomy on TTP. Methods: This historical cohort study used data from the Danish National Birth Cohort and the Danish National Patient Registry. The study population consisted of 86,323 women with 92,696 pregnancies. The main outcome was TTP; groups were compared using a binary outcome: TTP >12 months or TTP ≤12 months. Results: Women who had a fibroid diagnosis code before attempting to conceive (n = 92) had an increased risk of TTP >12 months compared with women without a fibroid diagnosis code (n = 87,358) (adjusted odds ratio [OR] 1.67; 95% confidence interval [CI] 1.05, 6.68). Women who had a fibroid diagnosis code after pregnancy (n = 963) also had an increased risk of TTP >12 months compared with women without a fibroid diagnosis code (adjusted OR 1.24; 95% CI 1.04, 1.47). Conclusion: We found an association between having a uterine fibroid diagnosis code and TTP >12 months. We were not able to make a valid assessment of the effect of myomectomy on TTP.