Inserter

1. A method capable of being performed with one hand, using an inserter to position an intrauterine system inside a uterus, the inserter comprising a handle, a slider, an insertion tube, and a removal string, the method comprising:

determining a depth of the uterus;

holding the handle with one hand;

inserting, with the one hand, the intrauterine system and the insertion tube into the uterus, wherein the removal string was immobilized by a lock prior to insertion of the intrauterine system; and

retracting, with a digit of the one hand, the slider so that a second end of the slider moves towards a second end of an opening of the handle and the lock pivots around a shaft or an axle to release the removal string.

2. The method of claim 1 , further comprising:

pushing, with the digit of the one hand, the slider forward so that a first end of the slider moves towards a first end of the opening of the handle.

3. The method of claim 1 , wherein the inserter further comprises a plunger and further comprising positioning the intrauterine system at a forward end of the plunger.

4. The method of claim 3 , wherein the lock reversibly locks the intrauterine system in relation to the plunger.

5. The method of claim 1 , wherein the lock includes a counterpart and a main part and, when the removal string is immobilized, the removal string is immobilized between the counterpart and the main part.

6. The method of claim 1 , wherein responsive to pushing with the one hand the slider forward, positioning the intrauterine system at a forward end of the insertion tube.

7. The method of claim 1 , wherein retracting with the one hand the slider so that the second end of the slider moves towards the second end of the opening of the handle causes the slider to press against an extension of a main part of the lock to turn the main part around the shaft or the axle on the handle to release the removal string of the intrauterine system.

8. The method of claim 1 , further comprising adjusting a flange on the insertion tube based on the depth of the uterus.

9. The method of claim 1 , wherein determining the depth of the uterus includes sounding the uterus using a probe.

10. The method of claim 1 , wherein the intrauterine system includes levonorgestrel.

11. The method of claim 1 , wherein the intrauterine system includes an active agent selected from the group consisting of progestin, estradiol, and gestodene.

12. The method of claim 1 , wherein the intrauterine system includes an active agent selected from the group consisting of 3-methoxy-17a-ethynyl-1,3,5 (10)-estratrien-17-ol (mestranol), 3-hydroxy-1,3,5 (10)-estratrien-17-one (estrone), 17p-estradiol, estriol, ethynylestradiol, 4-pregnene-3,20-dione (progesterone), d-13-ethyl-17a-ethynyl-17p-hydroxy-4-gonen-3-one (d-norgestrel) and the esters thereof, 17a-ethynyl-19-nortestosterone (norethisterone) and the esters thereof, 6-chloro-17-hydroxy-1a, 2a-methylenepregna-4, 6-diene-3,20-dione (cyproterone) and the esters thereof, 19-norhydroxyprogesterone and the esters thereof, 6-chloro-17-acetoxy-pregna-4,6-diene-3, 20-dione (chlormadinone acetate), 15, 16a-methylene- and 15, 16p-methylene-17p-hydroxy-18-methyl-17a-ethynyl-4-estre n-3-one, 17a-acetoxy-6a-methylprogesterone (medroxy-progesterone acetate), 9ss, 10a-pregna-4,6-diene-3,20-dione (dydrogesterone), estradiol-3-methyl ether diethylstilbestrol, 17a-ethynyl-4-estrene-3 ss, 17 ss-diol diacetate, 17a-ethynel-11 ss-methyl-4 estrene 3ss, 170-diol 3,17-diacetate, 17a-acetoxy-llp-methyl-19-norpregn-4-en-3-one, testosterone, testosterone propionate, testosterone phenylacetate and related androgens, allyloestrenol, lynoestrenol, norgestrel, norethyndrel, norethisterone, norethisterone acetate, gestodene, levonorgestrel, medroxyprogesterone, megestrol, testosterone, methyltestosterone, clostebol acetate, drostanolone, furazabol, nandrolone oxandrolone, stanozolol, trenbolone acetate, dihydro-testosterone, 17-a-methyl-19-nortestosterone, norethindrone, etonogestrel, desogestrel, and fluoxymesterone.