The intrauterine device (IUD) is the most commonly used method of reversible contraception worldwide. However, it is used by only 1% of women in the United States who desire reversible contraception. The infrequent use in this country results from public fear of health risks, complicated and promoted by medicolegal factors.
The IUD was developed in the United States and was popular in this country until the mid-1970s, when the Dalkon Shield came into use and was associated with ascending uterine infections. This complication was not intrinsic to all IUDs, but was caused by use of a braided IUD string that provided a path for bacteria to enter the uterus. This resulted in ascending infections, pelvic inflammatory disease, and infertility. The device was removed from the market in 1975. Although other IUDs, especially those containing copper, were safe and effective, litigation and other economic factors led to most of them being removed from the market in the early 1980s.
The Copper T380A (ParaGard, Ortho-McNeil, Raritan, NJ), introduced in 1988, is now commonly used by primary care practitioners. It contains copper on a polyethylene T-shaped frame that is 32 mm wide and 36 mm long. It may be used for 10 years before replacement and has a failure rate of less than 1%. The Copper T380A is one of the most thoroughly studied IUDs. Careful patient selection, good patient education, and thorough informed consent have greatly reduced the medicolegal risk with this IUD. A 5-year IUD (Mirena, Berlex Laboratories, Montville, NJ) has emerged on the U.S. market. The major advantage of this device is the reduction of bleeding after 6 months of use. Approximately 20% of women experience amenorrhea after 1 year of use.
The primary mechanism of action of the Copper T380A IUD is probably through the spermicidal effects of the copper. Sperm are damaged in transit, and few reach the ovum. Those that do ascend are generally in poor shape. There also may be alterations in cervical mucus produced by the IUD. IUDs also cause a foreign body inflammatory reaction. The levonorgestrel-releasing system provides pregnancy prevention by thinning the lining of the uterus, inhibition of sperm movement, and thickening of cervical mucus. There is minimal scientific evidence (despite more than 30 years of study) that the IUD is an abortifacient. However, if a patient is not able to accept this as a possible minimal mechanism of action,
she may wish to consider an alternative form of birth control. IUDs have a lower actual failure rate in clinical use than oral contraceptives and most other reversible contraceptive methods. Fertility usually returns promptly after removal of an IUD.
The Copper T380A may be inserted any time after delivery, after abortion, or during the menstrual cycle. The advantages of insertion during a menstrual period include a possibly more open cervical canal, the masking of insertion-related bleeding, and the knowledge that the patient is not pregnant. Insertions can be more difficult when the cervix is closed between periods.
Insertion can be performed between 4 and 8 weeks postpartum without an increase in pregnancy rates, expulsion, uterine perforation, or removal for bleeding or pain. Insertion can even occur immediately after a vaginal delivery without an increased risk of infection, uterine perforation, postpartum bleeding, or uterine subinvolution if no infection is present. Expect a slightly higher expulsion rate compared with insertion 4 to 8 weeks postpartum. The IUD also can be inserted at the time of cesarean section, with the expulsion rate slightly lower than immediately after vaginal delivery. Insertion of an IUD in breast-feeding women is associated with a lower removal rate for bleeding or pain. An IUD can be inserted immediately after a first-trimester abortion, but the patient should wait after a second-trimester abortion until uterine involution occurs.
Patient satisfaction studies have revealed higher ratings for IUDs than for most other contraceptive methods. Increased menstrual bleeding and cramping is a typical side effect of IUD use. Bleeding causes removal of the T380A during the first year in 5% to 15 % of patients. Nonsteroidal antiinflammatory drugs often help reduce these problems.
Infections caused by IUDs usually occur within the first 20 days after insertion. The overall rate of infection is only 0.3%. Doxycycline (200 mg) or azithromycin (500 mg) may be given orally 1 hour before insertion to reduce the rate of insertion-related infections. Definitive studies that demonstrate benefits of prophylactic antibiotics with IUD insertion are yet to be performed and the need for them in women at low risk for sexually transmitted diseases (STDs) is questionable. Cases of tuboovarian actinomycosis associated with IUD use have been reported. If this organism is reported on a Papanicolaou (Pap) smear in an asymptomatic patient, the IUD should be removed and may be replaced when a repeat Pap smear is negative.
The ectopic pregnancy rate with use of the T380A is lower than with no contraception (90% reduction in risk). However, if a patient becomes pregnant with an IUD in place, it is more likely that the pregnancy is ectopic. There is no increase in ectopic pregnancy with a history of prior IUD use. Intrauterine pregnancy with an IUD in place causes a 20-fold increased risk of developing life-threatening, second-trimester septic abortion. The IUD therefore should be removed as early as possible if intrauterine pregnancy occurs.
Spontaneous expulsion occurs in 5% of women during the first year, most often during the first menses after insertion. Partial expulsion or displacement is marked by lengthening of the IUD string. The IUD may be immediately reinserted if no infection is present (prophylactic antibiotics are recommended).
Displacement of the IUD may occur, and absence of the string on the patient's self examination is cause for further evaluation. Plain films of the abdomen can determine the presence of the IUD, and ultrasonography or hysteroscopy can be used to determine its location or to extract the device. If the
device is in the abdominal cavity, laparoscopy is usually successful at removal. Uterine perforation may occur during insertion but is uncommon.
Patients with newly inserted IUDs should attempt to feel the strings before they leave the examining room. Give the patient the cut ends of the strings as a sample of what to feel. The patient should make a follow-up visit in 1 month to confirm presence of the IUD and to trim the string if it is too long. Palpation of the strings should be performed monthly by the patient to verify continuing presence of the IUD after each menstrual flow.
Explain the IUD insertion procedure, and obtain informed consent. With the patient in the lithotomy position, perform a bimanual examination to determine the uterine size and position and to rule out structural abnormalities. Place a sterile speculum in the vagina, and swab the cervix with an antiseptic solution such as an iodine or benzalkonium preparation. Make sure the IUD package is intact and that all of the parts are present.
(1) Examine the IUD package to make sure it is intact and contains all the pieces.
Using sterile technique, grasp the anterior lip of the cervix with a tenaculum and sound the uterus (should be between 6 and 10 cm). A paracervical block can be used to decrease the pain of the procedure. Inject 2% lidocaine just off the cervix at the 3- and 9-o'clock positions (or 4- and 10-o'clock positions if preferred).
(2) Grasp the anterior lip of the cervix with a tenaculum, and sound the uterus.
PITFALL: A paracervical block takes a few minutes for full effect. Wait 2 to 3 minutes following the injections before initiating the procedure.
With sterile gloves or through the sterile wrapper, fold down the arms of the IUD into the insertion tube just enough to hold them in place during insertion. The phlange on the insertion tube is set to the distance of the sounding. This permits visual confirmation of when the top of the IUD reaches the fundus.
(3) Using sterile gloves, fold down the arms of the IUD into the insertion tube just enough to hold them in place during insertion.
PITFALL: Fold the arms right before or during the procedure. Prolonged bending of the arms causes them to release slowly and increases the likelihood of device expulsion.
Insert the device into the uterine cavity until it meets resistance at the fundus; and then slightly withdraw (i.e., a few millimeters). While holding the insertion rod in place, withdraw the insertion tube 1 to 2 cm to release the arms of the IUD in the horizontal plane of the uterus.
(4) Insert the IUD into the uterine cavity until it meets the fundus, and then slightly withdraw the device.
PITFALL: Do not push the insertion rod upward to elevate the IUD. This practice is painful for the patient and increases the risk of perforation.
Withdraw the insertion rod and tube, leaving the string protruding from the cervical os. You can ensure that the Copper T380A is in a high fundal position if, after removing the solid rod, you push the insertion tube up against the cross arm of the T before withdrawing it.
(5) Withdraw the insertion rod and tube, leaving the string protruding from the cervical os.
Cut the string to a length that allows the patient to easily palpate it on self-examination (i.e., 2.5 to 4 cm).
(6) Cut the string to a length that allows the patient to easily palpate it on self-examination.
PITFALL: Do not cut the strings too short; err on the side of too long because the strings can always be cut again. If the strings are cut too short, they tend to impale the end of the glans penis and cause pain during intercourse.
PITFALL: Despite proper placement, early expulsion is possible. Inform the patient of this possibility, and instruct her to return the IUD to your office. The manufacturer will provide a sterile replacement for reinsertion at no cost.
Removal of an IUD usually can be accomplished by grasping the string with a ring forceps and exerting firm, steady traction (usually during the menstrual period).
(7) Grasp the string with ring forceps, and exert firm steady traction.
If strings cannot be seen, they can often be extracted from the cervical canal by rotating two cotton-tipped applicators or a Pap smear cytobrush in the endocervical canal.
(8) Strings can be extracted from the cervical canal by rotating two cotton-tipped applicators in the endocervical canal.
If IUD strings cannot be identified or extracted from the endocervical canal, a light plastic uterine sound should be passed into the endometrial cavity after administration of a paracervical block. The IUD can frequently be felt with the sound and localized against the anterior or posterior wall of the uterus. The device can then be removed using polyp- or alligator-type forceps directed to where the device was felt.
(9) If the IUD strings cannot be extracted from the endocervical canal, a light plastic uterine sound should be passed into the endometrial cavity.
PITFALL: Because there is a risk of perforation with this procedure, patients are often referred for hysteroscopic removal at this stage.
INSTRUMENT AND MATERIALS ORDERING
ParaGard IUDs can be obtained from Ortho-McNeil Pharmaceuticals (phone: 1-800-322-4966). A physician can establish an account free of charge and place orders for the product. They may be ordered singly or in a box of five at a lower cost per unit.
Mirena may be ordered from Berlex Laboratories, Inc. (phone: 1-866-647-3646). Before any insertion, it is important to obtain training on the proper technique specific to Mirena. Training can be found at http://www.mirena-us.com or by writing Berlex Laboratories, Inc., 6 West Belt Road, Wayne, NJ 07470-6806.
Instruments and materials in a standard gynecological tray are listed in Appendix B.
Croxatto HB, Ortiz ME, Valdez E. IUD mechanisms of action. In: Bardin CW, Mishell DR Jr, eds. Proceedings of the Fourth International Conference on IUDs. Boston; Butterworth-Heinemann, 1994.
Delbanco SF, Mauldon J, Smith MD. Little knowledge and limited practice: emergency contraceptive pills, the public, and the obstetrician-gynecologist. Obstet Gynecol 1997;89:1006–1011.
Hill DA, Weiss NS, Voigt LF, et al. Endometrial cancer in relation to intra-uterine device use. Int J Cancer 1997;70:278–281.
Mendelson MA. Contraception in women with congenital heart disease. Heart Dis Stroke 1994;3:266–269.
Mishell DR Jr. Intrauterine devices: mechanisms of action, safety, and efficacy. Contraception 1998;58(Suppl):45S–53S.
Nelson AL. The intrauterine contraceptive device. Obstet Gynecol Clin North Am 2000;27:723–740.
Ramirez Hidalgo A, Pujol Ribera E. Use of the intrauterine device: efficacy and safety. Eur J Contracept Reprod Health Care 2000;5:198–207.
Shelton JD. Risk of clinical pelvic inflammatory disease attributable to an intrauterine device. Lancet 2001;357:443.
Speroff L, Darney P. A clinical guide for contraception, 2nd ed. Baltimore: Williams & Wilkins, 1996.
Thonneau P, Goulard H, Goyaux N. Risk factors for intrauterine device failure: a review. Contraception 2001;64:33–37.
Trussell J, Koenig J, Ellertson C, et al. Preventing unintended pregnancy: the cost-effectiveness of three methods of emergency contraception. Am J Public Health 1997;87:932–937.
Zimmer DF. Avoiding litigation in a new age of IUDs. Obstet Gynecol Surv 1996;51:S56–S60.