Catheter for uterine cervix insertion

Abstract

To provide a catheter for uterine cervix insertion that can be inserted into the uterine cervix easily, which has improved operability and reduces invasiveness.SOLUTION: A catheter 100 for uterine cervix insertion includes a first shaft 10 having a lumen 13 and a guide wire member 20 having a leading end tip 21, a coil 22, and a core wire 23. The guide wire member 20 can move with respect to the first shaft 10 in the state of being disposed in the lumen 13 of the first shaft 10. In a natural state, the coil 22 includes a first part 2201 with a pitch P1 larger than a wire diameter of a wire 220, and a second part 2202 positioned at a proximal side relative to the first part 2201, with a pitch P2 smaller than that of the first part 2201. The catheter includes a curved section 101 in which the first shaft 10 is curved in a natural state.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a catheter for cervical insertion used during embryo transfer or artificial insemination.

Background Art

[0002] In infertility treatment, artificial insemination, in vitro fertilization, micro-insemination, embryo transfer, etc. are performed. In vitro fertilization is a method of injecting sperm around an egg placed in a culture solution to cause fertilization. Micro-insemination is a method of injecting sperm into an egg using a thin glass tube under a microscope to cause fertilization. Embryo transfer is a method of transplanting an embryo that has been fertilized and grown by in vitro fertilization or micro-insemination into the uterus of a patient at an appropriate timing. Artificial insemination is a method of increasing the probability that sperm reaches an egg by injecting sperm washed with a culture solution into the uterus.

[0003] When performing embryo transfer, for example, an embryo transfer instrument as described in Patent Document 1 is used.

[0004] Patent Document 1 describes an embryo transfer instrument including a flexible sheath having a passage penetrating from the tip to the rear end and a spherical bulge, a flexible stylet removably inserted into the flexible sheath and having a tip substantially equal to or slightly protruding from the front end face of the flexible sheath, and a transplantation tube body having a flexible tip portion that can be inserted into the flexible sheath with the flexible stylet removed and can protrude a predetermined length from the tip of the flexible sheath.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the embryo transfer device described in Patent Document 1, a flexible stylet was disposed in the lumen of a flexible sheath, and a part thereof was curved. However, there are still many cases where it is difficult to place the distal end of the flexible sheath in which the flexible stylet is disposed in the uterine cavity due to stenosis or bending of the cervical canal. In such cases, even when a force is applied to the flexible sheath in which the flexible stylet is disposed, the force escapes in the direction of further bending of the bent portion, making it difficult to apply a straight force in the desired direction to advance the sheath. In such cases, the tissue of the cervix was pulled while being grasped by the instrument, or the distal end of the flexible sheath in which the flexible stylet was disposed was pushed into the cervix using forceps. For this reason, depending on the skill of the doctor, it may take a lot of time to place the flexible sheath in the uterus, or it may be accompanied by bleeding from the tissue, and there are problems from the viewpoints of operability and invasiveness.

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide a catheter for cervical insertion that can improve operability, reduce invasiveness, and is easy to insert into the cervix.

Means for Solving the Problems

[0008] The catheter for cervical insertion according to an embodiment of the present invention that has solved the above problems is as follows. [1] A first shaft having a first end, a second end located proximal to the first end, and a lumen extending from the first end to the second end, A guide wire member including a tip chip, a coil around which a wire having a first end and a second end located proximal to the first end is wound, wherein the first end of the wire is connected to the tip chip, and a core wire connected to the tip chip and disposed in the lumen of the coil. The guide wire member is movable relative to the first shaft while being disposed in the lumen of the first shaft. In the natural state, the coil has a first portion having a pitch larger than the wire diameter of the wire, and a second portion located closer to the proximal side than the first portion and having a pitch smaller than the first portion. A catheter for cervical insertion having a curved section in which the first shaft is curved in the natural state.

[0009] In the catheter for cervical insertion according to the embodiment of the present invention, the traveling direction of the guide wire member can be easily adjusted by moving the core wire of the guide wire member from the distal side toward the proximal side or moving the core wire of the guide wire member from the proximal side toward the distal side. Thereby, the operability of the catheter for cervical insertion can be improved and the invasiveness can be reduced. Further, by moving the core wire toward the proximal side from the distal side with respect to the coil, the pitch that constituted the first portion of the coil in the natural state becomes narrower. Thereby, since the rigidity of the distal end portion of the guide wire member can be increased, it is possible to easily insert the catheter for cervical insertion into the cervix.

[0010] The catheter for cervical insertion according to the embodiment of the present invention is preferably any one of the following [2] to [8]. [2] The first shaft has a first engaging portion at its second end, The catheter for cervical insertion has an engaging member having a second engaging portion detachably configured with respect to the first engaging portion, The engaging member is the catheter for cervical insertion according to [1] to which the second end of the coil is connected and the core wire is not connected. [3] The first engaging portion is a concave portion, a convex portion, a male screw, or a female screw, The second engaging portion is the catheter for cervical insertion according to [2], which is a convex portion, a concave portion, a female screw, or a male screw. [4] The core wire has a first end and a second end located closer to the proximal side than the first end, The catheter for cervical insertion according to any one of [1] to [3], further comprising a connecting member to which the second end of the core wire is connected and to which the coil is not connected, and a supporting portion for supporting the connecting member. [5] The catheter for cervical insertion according to any one of [1] to [4], having a straight section that is located proximal to the curved section in a natural state and in which the first shaft extends linearly. [6] The catheter for cervical insertion according to [5], wherein the first portion is located in the curved section and the second portion is located in the straight section. [7] The catheter for cervical insertion according to any one of [1] to [6], wherein a pressure sensor is provided at the first end of the first shaft. [8] The first shaft has, at its first end, a bulging portion that bulges outward in the radial direction of the first shaft, and a gas is enclosed inside the bulging portion. The catheter for cervical insertion according to any one of [1] to [7]. [Advantages of the Invention]

[0011] The catheter for cervical insertion according to the embodiment of the present invention can improve the operability, reduce the invasiveness, and can be easily inserted into the cervix. [Brief Description of the Drawings]

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0013] Hereinafter, the present invention will be specifically described with reference to the drawings. However, the present invention is not limited to the illustrated examples, and it is also possible to appropriately modify and implement the invention within the scope that can conform to the gist of the foregoing and following descriptions, and all of them are included in the technical scope of the present invention. In each figure, for the sake of convenience, hatching, reference numerals, etc. may be omitted, but in such a case, reference shall be made to the specification and other figures. In addition, the dimensions of various components in the drawings may differ from the actual dimensions because priority is given to facilitating the understanding of the features of the present invention.

[0014] The catheter for cervical insertion according to an embodiment of the present invention includes a first shaft having a first end, a second end located proximal to the first end, and a lumen extending from the first end to the second end, a tip tip, a coil around which a wire having a first end and a second end located proximal to the first end is wound, with the first end of the wire connected to the tip tip, and a core wire connected to the tip tip and disposed in the lumen of the coil, and a guide wire member. The guide wire member is movable relative to the first shaft while being disposed in the lumen of the first shaft. In the natural state, the coil has a first portion having a pitch larger than the wire diameter of the wire and a second portion located proximal to the first portion and having a pitch smaller than that of the first portion, and the gist lies in the point that the first shaft has a curved section that is curved in the natural state.

[0015] Referring to FIGS. 1 to 6, the overall configuration of the catheter for cervical insertion according to the embodiment of the present invention will be described. In this drawing, a catheter 100 for cervical insertion including a first shaft 10 and a guide wire member 20 is shown. In this drawing, the longitudinal direction of the catheter 100 for cervical insertion is indicated by x, the radial direction by y, and the circumferential direction by c. For ease of understanding, in this drawing, the longitudinal direction of the first shaft 10 coincides with the longitudinal direction x of the catheter 100 for cervical insertion, the radial direction of the first shaft 10 coincides with the radial direction y of the catheter 100 for cervical insertion, and the circumferential direction of the first shaft 10 coincides with the circumferential direction c of the catheter 100 for cervical insertion. However, the present invention is not limited to this aspect.

[0016] In this specification, the proximal side refers to the direction toward the user's hand with respect to the longitudinal direction x of the catheter 100 for cervical insertion, and the distal side refers to the opposite side of the proximal side, that is, the direction of the treatment target side. Also, when each member or each part is bisected in the longitudinal direction x of the catheter 100 for cervical insertion, the portion located on the distal side of each member or each part is referred to as the distal part of each member or each part, and the portion located on the proximal side of each member or each part is referred to as the proximal part of each member or each part. The distal end of each member or each part is the end located on the most distal side of each member or each part. The proximal end of each member or each part is the end located on the most proximal side of each member or each part. The end portion includes the peripheral portion of the end. That is, the distal end portion refers to the distal end and the peripheral portion of the distal end, and the proximal end portion refers to the proximal end and the peripheral portion of the proximal end. Also, the first end portion refers to the first end and the peripheral portion of the first end, and the second end portion refers to the second end and the peripheral portion of the second end.

[0017] Figure 1 shows a side view of a catheter for cervical insertion according to an embodiment of the present invention. Figure 1 shows a side view when observed from the horizontal direction in the state of use. More specifically, the upper side toward the drawing is the upper side in the vertical direction, and the lower side toward the drawing is the lower side in the vertical direction. In this drawing, the horizontal direction coincides with the direction indicated by arrow x, and the vertical direction coincides with the direction indicated by arrow y. Figure 2 shows a cross-sectional view (partial side view) of the catheter for cervical insertion shown in Figure 1. Figures 1 and 2 show the catheter for cervical insertion in a natural state. Figure 3 shows a cross-sectional view (partial side view) showing the state when the core wire is moved from the distal side toward the proximal side in the catheter for cervical insertion shown in Figure 2. Figure 4 shows a cross-sectional view (partial side view) showing a modified example of the catheter for cervical insertion according to an embodiment of the present invention. Figure 5 shows an end face view of a cut portion along line V-V of the catheter for cervical insertion shown in Figure 3. Figure 6 shows an end face view of a cut portion showing a modified example of the catheter for cervical insertion shown in Figure 5.

[0018] As shown in FIGS. 1 to 3, the catheter 100 for cervical insertion preferably has a longitudinal direction x. The catheter 100 for cervical insertion includes a first shaft 10 and a guide wire member 20. At least a part of the catheter 100 for cervical insertion is inserted into the cervix.

[0019] As shown in FIGS. 1 and 2, the catheter 100 for cervical insertion has a curved section 101 in which the first shaft 10 is curved in a natural state. The catheter 100 for cervical insertion may have a straight section 102 that is located proximal to the curved section 101 and in which the first shaft 10 extends linearly in a natural state.

[0020] As shown in FIGS. 1 to 3, the first shaft 10 has a first end 11, a second end 12 located proximal to the first end 11, and a lumen 13 extending from the first end 11 to the second end 12.

[0021] As shown in FIGS. 2 and 3, the guide wire member 20 has a first end 203 and a second end 204 located proximal to the first end 203. The guide wire member 20 has a tip 21, a coil 22, and a core wire 23. The guide wire member 20 is configured to be movable relative to the first shaft 10 while being disposed in the inner cavity 13 of the first shaft 10. Examples of the mode in which the guide wire member 20 is movable relative to the first shaft 10 include a mode in which the first shaft 10 and the guide wire member 20 are not fixed and the relative position between the first shaft 10 and the guide wire member 20 can be moved, a mode in which the relative position between the first shaft 10 and the guide wire member 20 is fixed so as not to move and the relative position between the first shaft 10 and the guide wire member 20 can be released from the fixed state so as to be movable, and a mode in which the first shaft 10 and the guide wire member 20 are fixed and the relative position between the first shaft 10 and the guide wire member 20 can be moved. In addition, it is preferable that the guide wire member 20 is configured to be removable from the inner cavity 13 of the first shaft 10.

[0022] As shown in FIGS. 2 and 3, the tip 21 is a member provided at the distal portion of the guide wire member 20. The tip 21 is preferably provided at the first end portion of the guide wire member 20.

[0023] As shown in FIGS. 2 and 3, the coil 22 is formed by winding a wire 220. The wire 220 has a first end 221 and a second end 222 located proximal to the first end 221. The first end 221 of the wire 220 is connected to the tip 21.

[0024] As shown in FIG. 2, in the natural state, the coil 22 has a first portion 2201 having a pitch P1 larger than the wire diameter of the wire 220, and a second portion 2202 located closer to the proximal side than the first portion 2201 and having a pitch P2 smaller than the first portion 2201. Note that FIG. 3 shows the first portion 2201 and the second portion 2202 that the coil 22 had in the natural state. Further, FIG. 3 shows the curved section 101 and the straight section 102 that the catheter 100 for cervical insertion had in the natural state. Note that in this specification, the natural state refers to a state in which no external force is applied to the guide wire member 20.

[0025] The pitch is the interval from the central axis of an adjacent wire 220 to the central axis, and refers to the portion having the longest length. For example, as shown in FIG. 2, the pitch P1 varies depending on the location where the length of the interval from the central axis of an adjacent wire 220 to the central axis is measured. Therefore, the portion having the longest length among the intervals from the central axis of an adjacent wire 220 to the central axis is defined as the pitch.

[0026] As shown in FIGS. 2 and 3, the core wire 23 is connected to the tip chip 21 and is disposed in the inner cavity 223 of the coil 22.

[0027] In the cervical insertion catheter 100 according to the embodiment of the present invention, as shown in FIG. 3, the core wire 23 of the guide wire member 20 can be moved from the distal side toward the proximal side, or as shown in FIG. 2, the core wire 23 of the guide wire member 20 can be moved from the proximal side toward the distal side, so that the traveling direction of the guide wire member 20 can be easily adjusted. Thereby, the operability of the cervical insertion catheter 100 can be improved, and invasiveness can be reduced. Further, as shown in FIG. 3, by moving the core wire 23 relative to the coil 22 from the distal side toward the proximal side, the pitch P1 that constituted the first portion 2201 of the coil 22 in the natural state becomes narrower. Thereby, since the rigidity of the distal end portion of the guide wire member 20 can be increased, the cervical insertion catheter 100 can be easily inserted into the cervical portion.

[0028] When the cervical insertion catheter 100 is inserted into the cervical portion, it is preferable that a part of the cervical insertion catheter 100 is disposed in the uterus. It is more preferable that the distal end portion of the cervical insertion catheter 100 is disposed in the uterus.

[0029] The cervical insertion catheter 100 is preferably used when performing infertility treatment. In particular, it is preferably used when performing embryo transfer or artificial insemination.

[0030] The first shaft 10 preferably has flexibility. Thereby, the first shaft 10 can be easily deformed along the shape of the body cavity. Further, for shape retention, the first shaft 10 preferably has elasticity.

[0031] The first shaft 10 can have a cylindrical shape, a hollow cylindrical shape, a hollow polygonal columnar shape, or a combination of these shapes.

[0032] As the first shaft 10, a resin tube can be used. The resin tube can be manufactured, for example, by extrusion molding. The resin tube may be single-layered or may have a plurality of layers. In the longitudinal direction of the first shaft 10 or in the circumferential direction of the first shaft 10, a part of the first shaft 10 may be composed of a single layer and the other part may be composed of a plurality of layers.

[0033] The first shaft 10 can be composed of a synthetic resin such as a polyolefin resin (for example, polyethylene or polypropylene), a polyamide resin (for example, nylon), a polyester resin (for example, PET), an aromatic polyether ketone resin (for example, PEEK), a polyether polyamide resin, a polyurethane resin, a polyimide resin, a fluororesin (for example, PTFE, PFA, ETFE), etc. These may be used alone only one kind, or two or more kinds may be used in combination.

[0034] In the longitudinal direction of the first shaft 10, resins having different bending rigidities may be used for the first shaft 10. For example, the first shaft 10 may have a lower bending rigidity from the proximal side toward the distal side. Thereby, it becomes easier to improve the operability at the distal portion of the first shaft 10.

[0035] In the circumferential direction of the first shaft 10, resins having different flexural rigidities may be used. As shown in FIGS. 5 and 6, the first shaft 10 may have a first portion 141 made of resin and a second portion 142 made of resin having a lower flexural rigidity than the first portion 141 in the circumferential direction of the first shaft 10. Thereby, in the circumferential direction c of the catheter 100 for cervical insertion, there are a portion that is relatively easy to bend and a portion that is relatively difficult to bend. For this reason, the distal end portion of the catheter 100 for cervical insertion can easily move in a predetermined direction. In the case of the embodiment shown in FIG. 5, in particular, the distal end portion of the catheter 100 for cervical insertion can easily move in the direction in which the first portion 141 exists in the radial direction of the first shaft 10. In the case of the embodiment shown in FIG. 6, in particular, the distal end portion of the catheter 100 for cervical insertion can easily move in the direction in which the second portion 142 exists in the radial direction of the first shaft 10.

[0036] In the radial direction of the first shaft 10, resins having different flexural rigidities may be used. For example, the flexural rigidity of the first shaft 10 may decrease from the inner side in the radial direction toward the outer side in the radial direction of the first shaft 10. Thereby, it becomes easy to improve the operability of the first shaft 10 and it is possible to make it difficult to damage the tissue.

[0037] The first shaft 10 preferably has an inner surface 15 facing the lumen 13 of the first shaft 10 and an outer surface 14 facing the outside of the first shaft 10.

[0038] The outer surface 14 of the first shaft 10 is preferably coated with a hydrophilic polymer. Thereby, it is possible to easily insert the first shaft 10 into the cervical portion. Examples of the hydrophilic polymer include poly(2-hydroxyethyl methacrylate), polyacrylamide, polyvinylpyrrolidone, maleic anhydride copolymers such as methyl vinyl ether maleic anhydride copolymer, and polyethylene glycol.

[0039] The inner surface 15 of the first shaft 10 preferably has a portion made of a fluororesin or a polyolefin resin. Only a part of the inner surface 15 of the first shaft 10 may be made of a fluororesin or a polyolefin resin, or the entire inner surface 15 of the first shaft 10 may be made of a fluororesin or a polyolefin resin. Thereby, since the first shaft 10 easily slides with respect to the second shaft 60 described later, the operability of the catheter 100 can be easily improved.

[0040] The outer diameter of the first shaft 10 can be, for example, 1.0 mm or more, 1.3 mm or more, 1.6 mm or more, etc. Also, the outer diameter of the first shaft 10 can be, for example, 5.0 mm or less, 4.0 mm or less, 3.0 mm or less, etc.

[0041] The diameter of the inner cavity 13 of the first shaft 10 can be, for example, 3.0 mm or less, 2.5 mm or less, 2.0 mm or less, etc. Also, the diameter of the inner cavity 13 of the first shaft 10 can be, for example, 1.1 mm or more, 1.2 mm or more, 1.3 mm or more, etc. It is also preferable that the diameter of the inner cavity 13 of the first shaft 10 is such that the second shaft 60 can pass through.

[0042] As shown in FIG. 2, the first shaft 10 has a first end-side opening that communicates the inner cavity 13 of the first shaft 10 with the outside of the first shaft 10 at the first end of the first shaft 10, and may have a second end-side opening that communicates the inner cavity 13 of the first shaft 10 with the outside of the first shaft 10 at the second end of the first shaft 10.

[0043] The length of the first shaft 10 in the longitudinal direction x of the catheter 100 for cervical insertion can be, for example, 140 mm or more, 150 mm or more, 160 mm or more, etc. Also, the length of the first shaft 10 in the longitudinal direction x of the catheter 100 for cervical insertion can be, for example, 200 mm or less, 190 mm or less, 180 mm or less, etc.

[0044] As shown in FIGS. 1 to 3, it is preferable that a pressure sensor 16 is provided at the first end portion of the first shaft 10. By arranging the pressure sensor 16, it is possible to suppress tissue damage caused by applying too much force to the first shaft 10, and it becomes easier to suppress bleeding from the tissue. The pressure sensor 16 may be provided on the first end face of the first shaft 10.

[0045] As shown in FIGS. 1 to 3, it is preferable that the first shaft 10 has a bulging portion 17 bulging outward in the radial direction of the first shaft 10 at its first end portion. With the above configuration, it is possible to easily suppress the first end portion of the first shaft 10 from damaging the tissue. Although not shown, as an aspect of the first shaft 10, an aspect without a bulging portion is also allowed.

[0046] As shown in FIGS. 2 and 3, it is preferable that a gas 18 is enclosed inside the bulging portion 17. With the above configuration, the bulging portion 17 in which the gas 18 is enclosed can easily reflect ultrasonic waves preferably, and it becomes easier to improve the visibility at the first end portion of the first shaft 10. The space in which the gas 18 is enclosed may be only one or a plurality. Although not shown, as an aspect of the first shaft 10, an aspect having a bulging portion 17 but without gas enclosed inside the bulging portion 17 is also allowed.

[0047] As the gas 17, for example, air, nitrogen, or the like can be used.

[0048] The guide wire member 20 can be made of, for example, synthetic resins such as polyolefin resins (e.g., polyethylene and polypropylene), polyamide resins (e.g., nylon), polyester resins (e.g., PET), aromatic polyether ketone resins (e.g., PEEK), polyether polyamide resins, polyurethane resins, polyimide resins, fluororesins (e.g., PTFE, PFA, ETFE), etc., or metals such as stainless steel, carbon steel, nickel-titanium alloys, etc. These may be used alone or in combination of two or more. Note that the tip 21, coil 22, and core wire 23 that make up the guide wire member 20 may be made of the same material or different materials respectively.

[0049] The length of the first portion 2201 of the guide wire member 20 in the longitudinal direction x of the catheter 100 for cervical insertion may be longer or shorter than the length of the second portion 2202 of the guide wire member 20 in the longitudinal direction x of the catheter 100 for cervical insertion.

[0050] As shown in FIG. 2, in the natural state, it is preferable that the distal end portion of the guide wire member 20 protrudes from the first end 11 of the first shaft 10. In the natural state, it is more preferable that the tip 21 of the guide wire member 20 protrudes from the first end 11 of the first shaft 10. Thereby, the guide wire member 20 can be lengthened, so that it is easier to adjust the advancing direction of the catheter 100 for cervical insertion. Although not shown, in the natural state, the distal end portion of the guide wire member 20 is located within the lumen 13 of the first shaft 10 and does not protrude from the first end 11 of the first shaft 10, and such a mode is also acceptable.

[0051] The shape of the tip 21 can be, for example, cylindrical, conical, frustoconical, polygonal columnar, polygonal pyramidal, frustopyramidal, spherical, hemispherical, etc. As shown in FIGS. 2 and 3, it is preferably hemispherical.

[0052] The tip chip 21 is preferably not directly or indirectly fixed to the first end 11 of the first shaft 10. For example, it is preferable that the tip chip 21 is not fixed to the first end 11 of the first shaft 10 via other members, adhesives, etc. It is preferable that the tip chip 21 is not welded and fixed to the first end 11 of the first shaft 10.

[0053] The wire 220 of the coil 22 is preferably arranged to wind around the core wire 23. The shape of the coil 22 is spiral. The inner cavity 223 of the coil 22 is formed by the wire 220 being in a spiral shape. The coil 22 preferably has an outer surface 224 facing the resin tube 10 side and an inner surface 225 facing the inner cavity 223 of the coil 22.

[0054] The coil 22 may be a single-layer wound coil, a multi-layer wound coil, or a combination thereof. For example, FIGS. 2 and 3 show an example where the coil 22 is a single-layer wound coil.

[0055] The wire 220 constituting the coil 22 may be composed of a single linear member from the first end 221 to the second end 222, or the wire 220 may be composed of a plurality of linear members connected to each other in the longitudinal axis direction.

[0056] The pitch P2 of the second portion 2202 may all have the same width. The second portion 2202 may have pitches P2 of different widths depending on the position.

[0057] The pitch P2 of the second portion 2202 is preferably the same length as the wire diameter of the wire 220. It is more preferable that all of the pitches P2 of the second portion 2202 are the same length as the wire diameter of the wire 220. Further, in the second portion 2202, it is even more preferable that there is no gap between adjacent wires 220, that is, adjacent wires 220 are in close contact. Note that an aspect where only a part of the pitch P2 of the second portion 2202 is the same length as the wire diameter of the wire 220 is also acceptable.

[0058] The pitch P1 of the first portion 2201 may all have the same width. The first portion 2201 may have pitches P1 with different widths depending on the position.

[0059] In the first portion 2201, it is preferable that there is a gap between adjacent wire rods 220, that is, adjacent wire rods 220 are not in close contact. For example, the pitch P1 of the first portion 2201 can be 1.1 times or more, 1.3 times or more, 1.5 times or more, etc. of the wire diameter of the wire rod 220. The pitch P1 of the first portion 2201 can be 10.0 times or less, 8.0 times or less, 5.0 times or less, etc. of the wire diameter of the wire rod 220. An aspect in which only a part of the pitch P1 of the first portion 2201 is within the above range is also acceptable, but it is preferable that all of the pitch P1 of the first portion 2201 is within the above range.

[0060] As shown in FIG. 2, in the natural state, it is preferable that the first portion 2201 of the coil 22 is located in the curved section 101 of the catheter 100 for cervical insertion, and the second portion 2202 of the coil 22 is located in the straight section 102 of the catheter 100 for cervical insertion. The entire first portion 2201 of the coil 22 may be located in the curved section 101 of the catheter 100 for cervical insertion, or only a part of the first portion 2201 of the coil 22 may be located in the curved section 101 of the catheter 100 for cervical insertion. The entire second portion 2202 of the coil 22 may be located in the straight section 102 of the catheter 100 for cervical insertion, or only a part of the second portion 2202 of the coil 22 may be located in the straight section 102 of the catheter 100 for cervical insertion.

[0061] The shape of the core wire 23 is preferably linear, for example.

[0062] The core wire 23 has a first end 231 and a second end 232 located proximal to the first end 231. Preferably, the first end portion of the core wire 23 is connected to the tip chip 21, and more preferably, the first end 231 of the core wire 23 is connected to the tip chip 21. From the viewpoint of facilitating the operation of the position of the core wire 23 with respect to the coil 22, in the natural state, it is preferable that the second end 232 of the core wire 23 is located distal to the second end 222 of the coil 22.

[0063] As shown in FIG. 2, in the natural state, the position of the tip chip 21 in the longitudinal direction x of the uterine cervical insertion catheter 100 may be the same as the position of the distal end 220d of the wire 220 in the longitudinal direction x of the uterine cervical insertion catheter 100. More specifically, in the natural state, the position of the distal end 220d of the wire 220 in the longitudinal direction x of the uterine cervical insertion catheter 100 means that it is located between the distal end 21d of the tip chip 21 and the proximal end 21p of the tip chip 21 in the longitudinal direction x of the uterine cervical insertion catheter 100. In this case, in the natural state, the guide wire member 20 may be L-shaped.

[0064] As shown in FIGS. 1 to 3, the uterine cervical insertion catheter 100 may further include an engaging member 30.

[0065] The engaging member 30 is preferably provided with a configuration for easily moving the position of the core wire 23 with respect to the coil 22 from the distal side to the proximal side or from the proximal side to the distal side.

[0066] For example, a configuration may be provided in which the first shaft 10 has a first engaging portion 19 at its second end, and the engaging member 30 has a second engaging portion 31 configured to be detachable from the first engaging portion 19. In this case, it is preferable that the second end of the coil 22 is connected to the engaging member 30 and the core wire 23 is not connected. By releasing the engagement between the first engaging portion 19 and the second engaging portion 31, the guide wire member 20 can be moved relative to the first shaft 10 while being disposed in the inner cavity 13 of the first shaft 10, and the guide wire member 20 can be removed from the inner cavity 13 of the first shaft 10. Further, since the proximal end portion of the coil 22 is connected to the engaging member 30 but the core wire 23 is not connected, it becomes easy to move only the core wire 23 from the distal side toward the proximal side.

[0067] As the first engaging portion 19, for example, a concave portion, a convex portion, a male screw, or a female screw can be used. As the second engaging portion 31, for example, a convex portion, a concave portion, a female screw, or a male screw can be used. When a concave portion is used as the first engaging portion 19, a convex portion is used as the second engaging portion 31. When a convex portion is used as the first engaging portion 19, a concave portion is used as the second engaging portion 31. When a male screw is used as the first engaging portion 19, a female screw is used as the second engaging portion 31. When a female screw is used as the first engaging portion 19, a male screw is used as the second engaging portion 31. Note that it is preferable to use a leaf spring as the convex portion.

[0068] The catheter 100 for cervical insertion may further include a connecting member 40 to which the second end of the core wire 23 is connected and the coil 22 is not connected, and a support portion 50 that supports the connecting member 40. Thereby, it becomes easy to hold the catheter 100 for cervical insertion and move the core wire 23 from the distal side to the proximal side or from the proximal side to the distal side with one hand.

[0069] The connecting member 40 is preferably movable along the support portion 50 from the distal side to the proximal side or from the proximal side to the distal side. Thereby, it becomes easier to hold the catheter 100 for cervical insertion and move the core wire 23 from the distal side to the proximal side or from the proximal side to the distal side with one hand.

[0070] The support portion 50 may be a part of the engaging member 30 or may be constituted by a member provided separately from the engaging member 30.

[0071] The materials constituting the engaging member 30, the connecting member 40, and the support portion 50 are not particularly limited. For example, polyolefin resins such as polypropylene (PP) and polyethylene (PE), polyester resins such as polyethylene terephthalate (PET), polycarbonate resins, ABS resins, synthetic resins such as polyurethane resins can be used.

[0072] As shown in FIG. 4, the catheter 100 for cervical insertion may further have a lumen 61 penetrating in the longitudinal direction x of the catheter 100 for cervical insertion and a second shaft 60 disposed in the lumen 13 of the first shaft 10. The second shaft 60 is preferably disposed in the lumen 13 of the first shaft 10 after the first shaft 10 is inserted into the cervical portion. More specifically, the second shaft 60 is preferably disposed in the lumen 13 of the first shaft 10 after the first shaft 10 is inserted into the cervical portion and after the guide wire member 20 is removed from the lumen 13 of the first shaft 10. The second shaft 60 is preferably disposed in the lumen 13 of the first shaft 10 with an embryo or sperm disposed in the lumen 61. The embryo can be transplanted into the uterus by discharging the embryo from the second shaft 60. The sperm can be injected into the uterus by discharging the sperm from the second shaft 60.

[0073] In the longitudinal direction x of the catheter 100 for cervical insertion, the length of the second shaft 60 is preferably longer than the length of the first shaft 10. Thereby, it becomes easier to discharge the embryo or sperm from the second shaft 60 into the uterus.

[0074] The second shaft 60 preferably has a distal end 60a and a proximal end 60b. Further, the second shaft 60 preferably has an inner surface 60c facing the inner cavity 61 of the second shaft 60 and an outer surface 60d facing the outside of the second shaft 60.

[0075] Regarding the configuration related to the second shaft 60 such as the material constituting the second shaft 60, reference can be made to the parts described for the first shaft 10.

[0076] The outer diameter of the second shaft 60 can be, for example, 0.3 mm or more, 0.5 mm or more, 0.8 mm or more, etc. Also, the outer diameter of the second shaft 60 can be, for example, 2.0 mm or less, 1.6 mm or less, 1.2 mm or less, etc.

[0077] The diameter of the inner cavity 61 of the second shaft 60 can be, for example, 1.5 mm or less, 1.2 mm or less, 0.9 mm or less, etc. Also, the diameter of the inner cavity 61 of the second shaft 60 can be, for example, 0.1 mm or more, 0.2 mm or more, 0.3 mm or more, etc. It is also preferable that the diameter of the inner cavity 61 of the second shaft 60 is large enough for the embryo to pass through.

[0078] As shown in FIG. 4, the second shaft 60 has a distal side opening 61a communicating the inner cavity 61 of the second shaft 60 and the outside of the second shaft 60 at the distal end portion of the second shaft 60, and may have a proximal side opening 61b communicating the inner cavity 61 of the second shaft 60 and the outside of the second shaft 60 at the proximal end portion of the second shaft 60.

[0079] The length of the second shaft 60 in the longitudinal direction x of the uterine cervix insertion catheter 100 can be, for example, 300 mm or more, 340 mm or more, 380 mm or more, etc. Also, the length of the second shaft 60 in the longitudinal direction x of the uterine cervix insertion catheter 100 can be, for example, 600 mm or less, 550 mm or less, 500 mm or less, etc.

Explanation of Signs

[0080] 100: Catheter for cervical insertion 101: Curved section 102: Straight section 10: First shaft 11: First end of the first shaft 12: Second end of the first shaft 13: Lumen of the first shaft 14: Outer surface of the first shaft 15: Inner surface of the first shaft 16: Pressure sensor 17: Bulge 18: Gas 19: First engaging part 141: First part of the first shaft 142: Second part of the first shaft 20: Guide wire member 203: First end of the guide wire member 204: Second end of the guide wire member 21: Tip 21d: Distal end of the tip 21p: Proximal end of the tip 22: Coil 220: Wire 220d: Distal end of the wire 220p: Proximal end of the wire 221: First end of the wire 222: Second end of the wire 223: Lumen of the coil 224: Outer surface of the coil 225: Inner surface of the coil 2201: First part of the coil 2202: Second part of the coil P1: Pitch of the first part P2: Pitch of the second part 23: Core wire 231: First end of the core wire 232: Second end of the core wire 30: Engaging member 31: Second engaging part 40: Connecting member 50: Support part 60: Second shaft 60a: Distal end of the second shaft 60b: Proximal end of the second shaft 60c: Inner surface of the second shaft 60d: Outer surface of the second shaft 61: Lumen of the second shaft

Claims

1. A first shaft having a first end, a second end located proximal to the first end, and a lumen extending from the first end to the second end; A guide wire member comprising a tip, a coil around which a wire having a first end and a second end located proximal to the first end is wound, the first end of the wire being connected to the tip, and a core wire connected to the tip and disposed within the lumen of the coil; The guide wire member is movable relative to the first shaft while being disposed within the lumen of the first shaft; In a natural state, the coil has a first portion having a pitch larger than the wire diameter of the wire and a second portion located proximal to the first portion and having a pitch smaller than that of the first portion; A catheter for cervical insertion having a curved section in which the first shaft is curved in a natural state.

2. The first shaft has a first engaging portion at its second end; The catheter for cervical insertion has an engaging member having a second engaging portion configured to be detachable from the first engaging portion; The engaging member is connected to the second end of the coil and is the catheter for cervical insertion according to claim 1, to which the core wire is not connected.

3. The first engaging portion is a recess, a protrusion, a male thread, or a female thread; The second engaging portion is a protrusion, a recess, a female thread, or a male thread, and is the catheter for cervical insertion according to claim 2.

4. The core wire has a first end and a second end located proximal to the first end; The catheter for cervical insertion according to any one of claims 1 to 3 further includes a connecting member to which the second end of the core wire is connected and to which the coil is not connected, and a support portion that supports the connecting member.

5. In a natural state, the catheter for cervical insertion according to any one of claims 1 to 3 has a straight section located proximal to the curved section and in which the first shaft extends linearly.

6. The catheter for cervical insertion according to claim 5, wherein the first portion is located in the curved section and the second portion is located in the straight section.

7. The cervical insertion catheter according to any one of claims 1 to 3, wherein a pressure sensor is provided at the first end of the first shaft.

8. The cervical insertion catheter according to any one of claims 1 to 3, wherein the first shaft has a bulging portion bulging outward in the radial direction of the first shaft at the first end thereof, and a gas is enclosed inside the bulging portion.

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