TABLE 3.

Comparative Efficacy of the TCu380A IUD and the 52-mg LNG IUS Over 7 Years From Rowe et al., 2016²³

	TCu380A IUD	LNG IUS
No. of women	1,871	1,884
Woman-years of observation	10,088	7,903
No. of pregnancies	33	7^a
Cumulative pregnancy rate per 100 woman-years (95% CI)	2.5 (2.1, 2.9)	0.5 (0.3, 0.8)

Abbreviations: CI, confidence interval; IUD, intrauterine device; LNG IUS, levonorgestrel-releasing intrauterine system.
↵a No pregnancies were reported in years 6 and 7.