Intrauterine Contraceptive Devices And Inserters Therefor

Abstract

The present invention relates to intrauterine contraceptive devices in the general shape of a "7" having a transverse arm and a longitudinal arm dependent substantially from an end thereof; method of contraception by insertion of such a device into the uterus; instruments and methods for the insertion of intrauterine contraceptive devices into the uterus without employment of forces propelling said devices from the instruments in the direction of the uterine fundus.

Parent Case Text

This application is a continuation-in-part of my copending U.S. application Ser. No. 836,371 filed June 25, 1969, and now abandoned and claims the priority of an application Ser. No. 11535 filed in the Philippines on June 15, 1970.

Description

The present invention relates to intrauterine contraceptive devices; to methods of contraception employing said devices; to instruments for the insertion of an intrauterine contraceptive device into the uterus; to combinations, suitable for sterile packaging, of an intrauterine contraceptive device and an instrument for the insertion thereof into the uterus; and to methods of inserting an intrauterine contraceptive device into the uterus.

It is known in the prior art that the presence of a foreign object in the uterus discourages conception. This phenomenon has been medically exploited for the intentional prevention of conception by insertion into the uterus of so-called intrauterine contraceptive devices, such as the well-known Lippes loop, commonly comprising a ring, spiral, or zigzag of a physiologically inert material, commonly plastic.

The employment of these devices for the purposes of contraception has heretobefore been subject to a number of disadvantages. First, the devices of the prior art have generally been of such dimensions as tend in situ to distort the uterus in the dorso-ventral and lateral directions, thereby causing discomfort, bleeding, and muscular spasms tending to eject the contraceptive device from the uterus. Further, the structure of such devices has heretobefore not always been such as to discourage involuntary ejection thereof from the uterus. Also, the dimensions assumed by the prior art devices when in a form suitable for insertion into the uterus either prevent or make difficult their insertion into a nulliparous cervical canal. Dilatation is often necessitated and requires general anesthesia. Finally, the insertion of such intrauterine devices has heretobefore been accompanied by a significant danger of puncturing the uterine wall because insertion involves pushing a device from suitable carrier instrument into the uterus in the direction of the uterine fundus. By inadvertence or miscalculation, the physician inserting the device may unknowingly push the device into or through the uterine wall, thereby giving rise to serious medical complications.

According to the present invention, intrauterine devices of such dorso-ventral and transverse dimensions as minimize rejection reactions have been devised. The novel structure of said devices, further, discourages inadvertent or involuntary discharge of the device from the uterus. Also, instruments for the insertion of intrauterine contraceptive devices have been discovered, which instruments do not require pushing forces in the direction of the uterine fundus to deposit the devices in the uterus. The chances of inadvertent puncturing of the uterine wall are thereby minimized. Still further, combinations of these instruments with intrauterine devices, including not only devices known in the prior art but also the novel devices taught herein, have been discovered. These combinations particularly lend themselves to sterile packaging as an integral unit for immediate use by an attending physician and disposal after use. Finally, methods of preventing conception employing novel intrauterine contraceptive devices are disclosed herein, as are novel methods of inserting intrauterine devices into the uterus.

A better understanding of the present invention and of its many advantages will be had by referring to the following drawings, in which

FIG. 1 is a perspective view of an intrauterine device and an instrument for the insertion of said device into the uterus;

FIG. 2 is a sectional view through the intrauterine device of FIG. 1 along the line 2--2 of FIG. 1;

FIG. 3 is an enlarged side view of the instrument of FIG. 1, partially in section, showing the intrauterine device of FIG. 1 folded in anterior portions thereof;

FIG. 4 is an enlarged end view of the instrument of FIGS. 1 and 3, showing an intrauterine device present folded therein;

FIG. 5 is a front view, partly in section, showing the instrument of FIG. 1 inserted into the uterus and the contraceptive device of FIG. 1 partially emergent therefrom;

FIG. 6 is the same view as FIG. 5 showing the further emergence of the contraceptive device from the instrument for the insertion thereof;

FIG. 7 is the same view as in FIGS. 5 and 6 showing the intrauterine device in position in the uterus after withdrawal of the instrument for insertion;

FIG. 8 is a side view of another embodiment of an instrument for the insertion of an intrauterine device into the uterus, showing an intrauterine device in combination therewith;

FIG. 9 is a plan view of the instrument and device of FIG. 8,

FIG. 10 is a sectional view of this same instrument taken along line 10--10 of FIG. 8;

FIG. 11 is a further sectional view of this instrument and device taken along line 11--11 of FIG. 8;

FIG. 12 is still another sectional view of this instrument taken along line 12--12 of FIG. 8;

FIG. 13 is a side view of the instrument and device of FIGS. 8 - 12 showing the manner in which the instrument is readied for insertion into the uterus for introduction of an intrauterine device thereinto;

FIG. 14 is a side view of the same instrument, showing the instrument in situ in the uterus;

FIG. 15 is a side view like that in FIG. 14, showing a later stage in the insertion of an intrauterine device into the uterus;

FIG. 16 is the same view as in FIGS. 14 and 15 showing a still later stage in the insertion process, and particularly showing an intrauterine device present in the uterus and withdrawal of the inserting instrument therefrom;

FIG. 17 is a front view, in section, taken along line 17--17 of FIG. 16 showing an intrauterine device present within the uterus after insertion thereof is complete;

FIG. 18 is a scale drawing of an embodiment of the intrauterine device of the present invention;

FIG. 19 is an enlarged plan view, in section, of the device of FIG. 13 taken along line 199--19 of FIG. 13;

FIG. 20 is an enlarged plan view, in section, taken along line 20--20 of FIG. 15;

FIG. 21 is a perspective view of a preferred embodiment of the intrauterine device of this invention comprising a transverse arm and a longitudinal arm;

FIG. 22 is a sectional view through one section of the transverse arm of the intrauterine devices of FIGS. 21 and 28 along the line 22--22 of FIGS. 21 and 28;

FIG. 23 is a sectional view through another section of the transverse arm of the intrauterine device of FIG. 21 along the line 23--23;

FIG. 24 is a sectional view through the midsection of the longitudinal arm of the intrauterine devices of FIGS. 21 and 28 along the line 24--24;

FIG. 25 is a sectional view through an end section of the longitudinal arm of the intrauterine device of FIG. 21 along the line 25--25;

FIG. 26 is an enlarged perspective view of the longitudinal arm of a preferred alternate embodiment of FIG. 21 having a copper wire wrapped around the arm;

FIG. 27 is a sectional view through a section of the intrauterine device of FIG. 26 along the line 27--27;

FIG. 28 is a perspective view of an alternate embodiment of the intrauterine device of this invention comprising a transverse arm and a longitudinal arm with the transverse arm terminating in a substantially hemispherical nub;

FIG. 29 is a sectional view through one section of the transverse and longitudinal arms of the intrauterine device of FIG. 28 along the line 29--29 of FIG. 28;

FIG. 30 is a perspective view of an alternate embodiment of the intrauterine device of FIG. 28, as viewed from the line 30--30 of FIG. 28, having a copper wire wrapped around the longitudinal arm;

FIG. 31 is a sectional view of the aperture for attachment of filament means to the device of FIG. 28 along the line 31--31 of FIG. 28;

FIG. 32 is a partially sectional view of the intrauterine device of FIG. 28 loaded in a folded configuration within an inserter barrel;

FIG. 33 is a perspective view of the distal end of longitudinal arm 120 as viewed from the back side of FIG. 28;

FIG. 34 is a partially sectional view of the intrauterine device of FIG. 28 loaded in an alternate configuration with the transverse arm located outside of the inserter barrel.

Referring to FIGS. 1, 18, 21, 26 and 28 of the accompanying drawings, it will be seen that the novel intrauterine contraceptive devices of the present invention have the general shape of the numeral "7," and comprise transverse arm 110 and longitudinal arm 120 dependent therefrom substantially at one end thereof.

The transverse and longitudinal arms of the device are proportioned to be comfortably accommodated within the uterine cavity. Transverse arm 110 suitably has an overall length of from 20 to 38 millimeters, whereas longitudinal arm 120 is of such dimensions that the overall length of the device is from 28 to 40 millimeters. The preferred dimensions depend on the size of the uterus which is primarily dependent on the degree of parity. The multiparous, primiparous and nulliparous uteri are generally decreasing in size and may conveniently permit the use of correspondingly differently sized intrauterine devices. The transverse and longitudinal arms of the devices are coplanar and suitably have a thickness of from about 1 millimeter to about 3 millimeters at the thickest part.

As shown in FIGS. 1 and 18, transverse arm 110 can optionally have a flexure 130 substantially at the mid-point therein, flexed arm 110 being downwardly concave in the direction of longitudinal arm 120. If a line is drawn connecting the end points of transverse arm 110 and a perpendicular to this connecting line is dropped from the mid-point thereof, the terminal portion of longitudinal arm 120 suitably lies on the perpendicular. Since longitudinal arm 120 is dependent from an end of arm 110, longitudinal arm 120 is generally arcuate.

In the devices of FIGS. 21 and 28, transverse arm 110 has the shape of an arc and longitudinal arm 120 has an arched upper portion 132 and a generally straight lower portion 134. If the line of the longitudinal arm 120 is extended upwardly, it will intersect the transverse arm 110 at the uppermost portion of the arcuate transverse arm 110. The arched portion of transverse arm 110 is generally a substantially circular arc of between about 25.degree.-90.degree., preferably between about 40.degree.-60.degree., and the arched upper portion 132 of longitudinal arm 120 is generally a substantially circular arc of between about 45.degree.-120.degree., preferably between about 80.degree.-120.degree.. Such construction enables the arms to be folded with minimum stress, i.e., the transverse arm and the longitudinal arm can be folded in such a manner that the folded transverse diameter will not be greater than the two transverse arms and it will retain its shape.

The devices of FIGS. 18, 21 and 28 are suitably made in whole or in part of a rigid but flexible physiologically inert material, commonly a plastic such as polyethylene, polypropylene, nylon, a poly (organo siloxane) such as that sold under the trademark Silastic, "Dacron" or the like. Polypropylene is particularly preferred. Barium sulfate or other barium compounds may be used with the above materials as an aid in detecting the presence of the device in the uterus. The device can also be constructed in whole or in part of a metal such as silver, gold, platinum or preferably copper or zinc.

Because of the device's small size and high retentive properties, the device is an excellent carrier for more active fertility regulating materials, especially elemental copper or zinc or both. For example, as shown in FIGS. 26 and 30, zinc wire, copper wire, or copper tubing 136 can be wound around the arms. Other means of applying the metals are vacuum metallizing, partial impregnation of metallic granules, and the use of one or more shaped forms such as a chain or wire dependent from an arm.

Although the intrauterine device of the present invention can have cylindrical arms as shown in FIGS. 1 and 18, the arms of the device can also be in the shape of semi-cylinders as shown in FIGS. 22, 24 and 29. These meet at a cylindrical apex 144, as shown in FIGS. 23, or at a substantially hemispherical nub 151, as shown in FIG. 28, the arms being designed in such a manner that when the device is folded, the flat portions come in contact and the folded device takes up a smaller amount of space, as shown in FIGS. 21-24. The limited amount of space taken up by the device in its folded configuration is particularly desirable since the device can then be inserted easily into nulliparous or primiparous patients with no dilation of the cervical canal being required.

In the device of FIG. 28, transverse arm 110 terminates in a generally rounded protuberance 151, preferably a substantially hemispherical nub, and longitudinal arm 120 is dependent therefrom. This novel configuration provides a gently rounded surface at the anterior end of the inserter barrel when the intrauterine device is loaded in its folded configuration within the barrel of the inserter as shown in FIG. 32. That rounded surface facilitates insertion of the device into the cervical canal and minimizes any irritation which might occur. Typically, nub 151 is of sufficient diameter to cover the edges of the insertion tube when the device is loaded in its folded configuration as shown in FIG. 32. Furthermore, the rounded nub allows the loaded inserter instrument to be used as a uterine sounding device.

Notch 152 on nub 151, as shown in FIGS. 29 and 30, and groove 154, as shown in FIGS. 31 and 33, provide space for the placement of filament means attached to the distal end of longitudinal arm 120 when the device of FIG. 28 is located in its folded configuration within the barrel of an insertion instrument as shown in FIG. 32. The device of FIG. 28 may be loaded in an alternate folded configuration within the inserter as shown in FIG. 34 wherein transverse arm 110 is located outside of the inserter barrel and longitudinal arm 120 is singularly located within the inserter barrel.

As shown in FIG. 30, notches 153 provide locations for embedment of the ends of the copper wire 136 which is optionally wrapped on longitudinal arm 120.

The device of FIG. 1, shown in section in FIG. 2, comprises resilient core 150 made of material such as spring wire (e.g. piano wire) having coating 160 thereover. Coating 160 is suitably of a physiologically inert substance such as those mentioned just above. Additional resilience and ease of flexion is achieved in the alternate device of FIG. 1 by forming coils 170 at flexure 130 of transverse arm 120 and at the point at which longitudinal arm 120 is attached thereto.

Physiologically inert filament 180 is suitably attached to terminal portions 140 of the devices of FIGS. 1 and 18 to facilitate their removal from the uterus and, as will be seen, in some cases to aid in their insertion into the uterine cavity. As shown in FIGS. 21, 25 and 28, the filament can be emplaced in aperture 148.

FIG. 1 further shown tubular instrument 190 comprising barrel 200 for accommodation of an intrauterine device. Stop means 21 are located on the exterior portions of instrument 190 at a distance from anterior end 22 thereof corresponding with a depth to which it is desired to insert barrel 20 into the uterine cavity. Means 23 are provided at the posterior end of instrument 190 to facilitate grasping and manipulation of the instrument.

FIGS. 3 and 4 show the intrauterine device of FIG. 1 and FIG. 21 mounted within barrel 200 of instrument 190 of FIG. 1. As is best seen from FIG. 3, transverse arm 110 of the device is bent downward from the point of attachment to longitudinal arm 120 to lie along an axis substantially parallel to that of the longitudinal arm, which position also requires some straightening of arm 110 at flexure 130 in the case of the intrauterine device of FIG. 1. Distortion of the device in this manner is possible because of the inherent resiliency of the material of core 150 as well as structural features such as coils 170. The device is loaded within instrument 190 such that terminal portion 140 of longitudinal arm 120 is farthest from anterior orifice 22. Filament 180 extends from terminal portion 140 out of orifice 22.

As is best seen from FIG. 4, barrel 200 is suitably elliptic in shape, whereby the folded device is constrained within a plane fixed with respect to inserting instrument 190.

FIGS. 5 - 7 show the insertion of a contraceptive intrauterine device according to the present invention into the uterus employing instrument 190 of FIG. 1. In particular, FIG. 5 shows instrument 190 in situ with barrel 200 inserted into uterus 24 until stop means 21 abut exterior cervical os 25. By pulling on filament 180 downwards in the direction of the arrow, said filament extending from anterior orifice 22 backwards along barrel 200 into the vagina 26, the contraceptive device lodged in barrel 200 is pulled therefrom until emergence from anterior orifice 22 of coil 170 at the junction of transverse arm 110 and longitudinal arm 120. The arcuate shape of longitudinal arm 120 and the resilience of folded transverse arm 110 tend to embed the juncture (coil 170) firmly into the uterine wall at point 27. Because of this embedment at point 27, further pulling on filament 180 exerts a downward force on the rim of barrel 200 at anterior orifice 22 tending to retract barrel 200 from the uterus.

This stage is shown in FIG. 6 of the accompanying drawings in which barrel 200 is shown sufficiently retracted from uterus 24, and from the intrauterine device therein, to permit escape of entire transverse arm 110. Lateral pressure exerted by the resilient material of the device around flexure 130 tends to embed the free end of transverse arm 110 into the uterine wall at point 28.

Finally, FIG. 7 shows the intrauterine device in situ in the uterus after complete withdrawal of the inserting instrument. It will be evident from FIG. 7 that the device is firmly anchored in the uterine cavity at points 27 and 28 already discussed, as well as at point 29 at which terminal portion 140 of longitudinal arm 120 makes contact with the uterine wall. This three point contact is highly effective in preventing inadvertent dislodgement or expulsion of the device from the uterus.

As will further be seen from FIGS. 5 - 7, it is evident that deposition of the intrauterine device within uterine cavity 24' has been accomplished without pushing forces tending to move the device in the direction of uterine fundus 30. Once the device has been sufficiently expelled from barrel 200 for one end of transverse arm 110 to make contact with the uterine wall (cf. point 27 of FIG. 5), further tension on filament 180 repels barrel 200 from uterus 24, rather than propelling the intrauterine device from the barrel. In this manner, the danger of puncturing uterine fundus 30 due to the propulsion of an intrauterine device into the uterus by pushing forces is greatly reduced.

FIGS. 8 - 12, in which the reference numbers respectively refer to the same structural features, show a preferred embodiment of an instrument for the insertion of an intrauterine contraceptive device into the uterus.

The device shown in these Figures comprises first barrel 31 having exterior stop means 32 positioned therealong at a distance from anterior orifice 33 of barrel 31 corresponding to a desired depth to which barrel 31 is to be inserted into the uterus.

The device shown in these figures similarly has second barrel 34 adjacent said first barrel and having a slot or keyway 35 (best seen in FIGS. 11 and 12) therein. Bifurcate piston 36 slides within barrels 31 and 34, and has first fork 37 in barrel 31 and second fork 38 in barrel 34. Second fork 38 of piston 36 is provided with stop means 39 external to barrel 34 movable within keyway 35 therein, as is best seen from FIG. 10.

First and second barrels 31 and 34 suitably have common grip means 40, advantageously fashioned to engage with the index and middle finger of the hand. Similarly, piston 36 is provided with handle means 41 which, when actuated (for example by thumb pressure), cause simultaneous movement of piston forks 37 and 38 within barrels 31 and 34 respectively.

The instrument of FIGS. 8 - 12 is there shown in combination with an intrauterine device like that of FIG. 18 comprising transverse arm 110, longitudinal arm 120, and filament 180 attached thereto. The intrauterine device is suitably loaded into the instrument of FIGS. 8 - 12 by insertion into transverse slot 42 in barrel 31 posterior to stop means 32. Longitudinal arm 120 lies axially within barrel 31, which is advantageously further slotted in an axial direction. Suitably, one or two axial slots are provided to accommodate a transverse arm or arms of an intrauterine device. These axial slots and their function can best be seen and understood by referring to FIGS. 13, 14, and 19, and to FIGS. 15 and 20.

In particular, FIGS. 13, 14, and 19 show an intrauterine contraceptive device positioned within barrel 31 of the instrument shown in FIGS. 8 - 12. Transverse arm 110 of the device extends from barrel 31 in one direction through axial slot 43 and, in the other direction, through somewhat longer axial slot 44. Longitudinal arm 120 of the device is within barrel 31 and extends axially therealong. This "start" or "rest" position of the intrauterine device is shown in FIG. 19 in dashed lines and represents the preferred position of the intrauterine device in the inserting instrument at the time of sterile packaging. In this position, no forces are exerted on the flexible intrauterine device which might tend to distort of malform it.

When the physician intends to insert an intrauterine device using the combination shown in FIG. 13, he opens the sterile package in which the device and inserting instrument are packed. As shown in FIGS. 13 and 14, barrels 31 and 34 are conveniently grasped with one hand and movable piston 36 with the other. The device is then inserted into uterus 24, as in FIG. 14, until stop 32 on barrel 31 makes contact with exterior cervical os 25. Then, as shown in FIG. 15, pressure is applied to handle means 41 against counterpressure applied to grip 40 to advance piston 36 forwards in barrels 34 and 31 until stop means 39, external to barrel 34 and traveling in the keyway therein, also make contact with external cervical os 25.

As is best seen from FIG. 19, advancement of piston fork 37 within barrel 31 causes the intrauterine device therein to fold itself within barrel 31 into the position shown in solid lines in FIG. 19. To distinguish the rest position and the folded position in FIG. 19, the reference numerals referring to the folded position have been primed.

Thus, upward pressure on piston 37 of FIG. 19 causes arm 110 of the intrauterine device to pivot counter-clockwise around a pivot point at the upper end 45 of shorter axial slot 43. As further upward pressure is exerted on the device by piston 37, transverse arm 110 ascends, enters longer axial slot 44 in barrel 31, and folds back on longitudinal arm 120 until the arms assume the positions 110' and 120' shown in solid lines in FIG. 19. The folding of the device within barrel 31 also causes some advancement of the device within the barrel, e.g. such that terminal portion 140 moves to a new position 140'.

When stop 39 external to barrel 34 contacts exterior cervical os 25, as shown in FIG. 15, because of upward pressure on piston fork 38, piston fork 37 will have accomplished the folding of the intrauterine device within barrel 31 anc caused advancement of the device substantially to anterior orifice 33 of barrel 31, as shown in FIG. 15 and, particularly, in FIG. 20. At this time, the device is in position in the uterus, but is still sheathed within barrel 31. In the region of orifice 33, interior 31' of barrel 31 is preferably elliptic to maintain the device in a fixed plane with respect to the instrument (cf. FIG. 12).

As shown in FIG. 16, further pressure on handle means 41 cannot cause further forward movement of piston 36 because of the impedance of the forward movement of piston fork 38 by contact of stop means 39 thereon with exterior cervical os 25. Rather, the instrument, comprising barrels 34 and 31, will tends to retract from the uterus in the direction of the arrow shown in FIG. 16, permitting the escape of the folded intrauterine device from anterior orifice 33. Piston fork 37 within barrel 31 retains a fixed position relative to the uterus during this stage. It is the retrograde movement of barrel 31 downwards along piston fork 37 which causes unsheathing of the device within the uterus. The instrument is withdrawn from around the intrauterine device when the device is in situ in the uterus. There is no propulsion of the device from the instrument by any pushing forces in the direction of uterine fundus 30. Proper planarity of the device with respect to the uterus is assured by elliptic interior 31' of barrel 31 and by the proper orientation of barrel 31 (and the instrument) to the uterine cavity.

FIG. 17 shows the device in situ in uterus 24 after insertion. As in FIG. 7, lateral and longitudinal arms 110 and 120 of the device make a three-point contact with the uterine wall at points 27, 28, 29, imparting particular stability to the device against accidental dislodgement from the uterus.

It is to be understood that the instrument shown in FIGS. 8 - 12 need not be used in conjunction with novel "7"-shaped intrauterine contraceptive devices particularly shown in the drawings and described in this specification. Rather, a device of a shape known in the prior art, such as a zig-zag or vermiform device, may be loaded within barrel 31 of the instrument prior to sterilization and packaging. Pre-packaging of a device of such a shape, however, entails the risk that the device will become distorted while constrained within the barrel 31 of the instrument, especially on long storage.

The instrument shown in these Figures can, however, also be employed with other intrauterine devices which are packed in combination with the instrument in an unstrained state. For example, thus, the "7"-shaped device of the present invention can be replaced with a "T"-shaped device, in which case it is suitable to make axial slots 43 and 44 in barrel 31 of the instrument (cf. FIG. 19) of substantially equal length. Pressure on piston 36 causes fork 37 thereof to fold such a "T"-shaped device into barrel 31 in the shape of an arrow, with the arms of the "T" folded back along the longitudinal arm.

Still further, a contraceptive device in the shape of an inverted "L" can be combined in an unstrained condition with the instrument of FIGS. 8 - 12. For folding such a device, the transverse arm of the "L" may extend from a single axial slot in barrel 31, or an axial slot may be dispensed with altogether, in which case the transverse arm merely extends from transverse slit 42 in barrel 31.

The material from which the instruments contemplated according to the present invention can be fashioned is not critical. However, the use of plastics is particularly convenient because the devices can be cheaply manufactured and then disposed of after use. The manufacture of the barrel from transparent or semi-transparent plastic materials permits the physician to observe the proper functioning of the device.

Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of this invention.

Claims

What is claimed is:

1. An intrauterine device consisting essentially of two arms formed of physiologically inert material and adapted to be placed in a uterus, a first arcuate transverse arm and a second arcuate substantially longitudinal arm coplanar with said first arm and substantially dependent from one end thereof, said first transverse arm bending concavely downwardly toward said second arm and said second arm bending concavely downwardly from said first arm the major portion of said second arm extending generally along a line through the upper most point of said first arm.

2. An intrauterine device as in claim 1 wherein said first and second arms are formed from a continuous length of spring wire having a physiologically inert coating thereon.

3. An intrauterine device as in claim 2 wherein the physiologicaly inert coating is polypropylene.

4. An intrauterine device as in claim 2 wherein the outside surface further contains copper.

5. An intrauterine device as in claim 4, wherein a copper wire is wound around at least one of the arms.

6. An intrauterine device as in claim 1 in which the transverse arm has a downwardly concave flexure substantially in the midpoint thereof.

7. An intrauterine device as in claim 1 in which said transverse arm terminates in a generally rounded protuberance.

8. An intrauterine device as in claim 7 in which the outside surface contains copper.

9. An intrauterine device as in claim 8 in which at least one of said arms is wrapped with copper wire.

10. An intrauterine device as in claim 8 in which at least one of said arms is plated with metallic copper.

11. An intrauterine device as in claim 1 in which said transverse arm has a portion thereof in the shape of a substantially circular arc and said longitudinal arm has an upper portion thereof in the shape of a substantially circular arc and a lower portion thereof which is substantially straight.

12. An intrauterine device as in claim 11 in which said transverse arm is between about 20 and 38 millimeters in length and the overall length of said device is between about 28 and 40 millimeters, said arms having a thickness of between about 1 and 3 millimeters at their thickest part.

13. An intrauterine device as in claim 12 in which said arc of said transverse arm is between about 25-90.degree. and said arc of said upper portion of said longitudinal arm is between about 45-120.degree..

14. An intrauterine device as in claim 1 in which the outside surface contains copper.

15. An instrument for the insertion of an intrauterine device into the uterus, said instrument comprising first barrel means for accommodation of said intrauterine device, said first barrel means having first stop means external to said barrel means in the anterior portion thereof at a distance from the anterior end of said first barrel means corresponding with a desired depth of insertion of said first barrel means into the uterus; second barrel means adjacent said first barrel means and extending to said first stop means, said second barrel means having a keyway therein; and bifurcate piston means in said first and second barrel means, said piston means having second stop means at the anterior end thereof, said second stop means being external to said second barrel means and traveling in said keyway therein.

16. An instrument as in claim 15 wherein said first barrel means are transversely slotted posterior to said first stop means for accommodation of an intrauterine device partially within and partially without said first barrel means.

17. An instrument as in claim 15 wherein said first barrel means are axially slotted posterior to said first stop means for accommodation of an intrauterine device partially within and partially without said first barrel means.

18. An instrument as in claim 15 wherein at least that portion of said first barrel means forward of said first stop means has an elliptic cross-section.

19. In combination suitable for sterile packaging, an instrument as defined in claim 15 and an intrauterine device in said first barrel means thereof.

20. A combination as in claim 18 wherein said intrauterine device comprises a first transverse arm having a downwardly concave flexure substantially in the midpoint thereof and a second arcuate arm, coplanar with said first arm and substantially dependent from one end thereof.

21. A combination as in claim 20 wherein said device is folded within said first barrel means.

22. In combination suitable for sterile packaging, an instrument as defined in claim 16 and an intrauterine device in said first barrel means thereof, said device comprising a transverse arm and a longitudinal arm dependent therefrom, said dependent arm lying axially within said first barrel mean and said transverse arm extending outwardly from transversely slotted portions of said first barrel means.

23. In combination suitable for sterile packaging, an instrument as defined in claim 17 and an intrauterine device in said first barrel means thereof, said device comprising a first transverse arm having a downwardly concave flexure substantially in the midpoint thereof and a second arcuate arm, coplanar with said first arm and substantially dependent from one end thereof, said second arcuate arm being positioned axially within said first barrel means and said first transverse arm extending outwardly from axially slotted portions of said first barrel means.