Table 4.

Incidence for women who received myomectomy among time lag.

Diagnosis-to-surgery period (year)	CM nonusers			CM users			cHRa	(95% CI)	aHRb	(95% CI)
	Patients with surgery	Person-years	IR	Patients with surgery	Person-years	IR
Overall	2074	19994	103.73	1607	90744	17.71	0.20	(0.18–0.21)***	0.18	(0.17–0.19)***
>0.25	882	19922	44.27	1483	90732	16.34	0.38	(0.35–0.41)***	0.33	(0.30–0.36)***
>0.5	731	19863	36.80	1416	90705	15.61	0.43	(0.39–0.47)***	0.37	(0.34–0.41)***
>1	562	19730	28.48	1285	90601	14.18	0.50	(0.45–0.55)***	0.42	(0.38–0.47)***
>3	253	19060	13.27	871	89670	9.71	0.72	(0.63–0.83)***	0.59	(0.51–0.68)***
≥5	91	18346	4.96	455	87840	5.18	1.01	(0.80–1.26)	0.79	(0.63–0.99)*

^acHR: crude HR.

^baHR: HR adjusted for age, occupation, area, excessive menstruation, iron-deficiency anemia, and dysmenorrhea.

*P < 0.05 and ***P < 0.0001.