Common adverse effects
The most common adverse effect seen with all LARC devices is an alteration in menstrual bleeding, and a frequent adverse effect with IUDs is pain. Vaginitis is less common and can be seen with any of the devices. The progestin-containing LARC devices are associated with hormonal effects: vaginitis, headache, weight gain, acne, breast pain, hair loss, and emotional lability.12-15
Copper IUD. Many women using the copper IUD experience either a transient increase in menstrual bleeding lasting for a few months or inter-menstrual bleeding that tends to continue for the duration of use.4,17 However, according to data from the Contraceptive CHOICE Project, the most common reason cited for early discontinuation of the copper IUD is pain and cramping.9
LNG-IUDs. Like the copper IUD, many users of LNG-IUDs experience an initial increase in menstrual bleeding. However, unlike the other LARC devices, 20% to 33% of Mirena users are likely to experience amenorrhea after one year of use and 70% at 2 years.4,14 According to package inserts, amenorrhea after 3 years is less common with both Skyla (12%) and Liletta (38%).12,13 As with the copper IUD, based on data from the Contraceptive CHOICE Project, the most common reason cited for early discontinuation of LNG-IUDs is pain and cramping.9
Subdermal implant. Changes in menses in women using the subdermal implant range from amenorrhea (22%) to prolonged bleeding (18%).15,17 Although it is difficult to predict which pattern a particular woman will experience, heavier women are more likely to have heavier bleeding patterns, and initial bleeding patterns are predictive of future ones.4 The most common reason women choose to discontinue use of the implant is abnormal bleeding.4,9,27,28
Newer IUDs do not increase risk of STIs
Many patients and clinicians erroneously believe that IUDs increase the risk of STIs and therefore assume that patients with a history of STI are not appropriate candidates for an IUD.29 There is a slightly increased risk of pelvic inflammatory disease (PID) in the first 21 days after insertion of an IUD. However, in contrast to older IUDs, currently available IUDs do not increase the general risk for STIs.17,30
Risk of infertility is nil
There is no risk of infertility from use of currently available LARCs. For those who want to become pregnant, fertility typically returns immediately after removal of the device, regardless of which method of LARC is used.11-15,30
Complications of IUD insertion
Uterine perforation. Uterine perforation occurs in 0.8 to 2.1 per 1000 women, usually at the time of IUD placement. If IUD strings are not visible during a speculum examination, locate the IUD with ultrasound.4,17,30 If the IUD is in the abdomen, refer to a gynecologist for laparoscopic removal and select another form of contraception for use in the interim.30
Expulsion. Rates of expulsion are low, occurring in less than 10% of women4,17 and are not affected by parity or BMI.31 Expulsion rates are higher when the IUD is inserted immediately postpartum.4,25,26 Adolescents also have a 2-fold higher risk of uterine expulsion than older women.31
Ectopic pregnancy. Although a woman’s overall risk of ectopic pregnancy is not increased by using an IUD,4 it is true that if a woman becomes pregnant with an IUD in place, the pregnancy is more likely to be ectopic. Thus, if pregnancy is confirmed in a woman with an IUD in place, rule out ectopic pregnancy.
The FDA and the World Health Organization recommend that if an intrauterine pregnancy is confirmed with an IUD in place and the strings are visible, the IUD should be removed.4 Although removing the IUD increases the risk of spontaneous abortion (SAB) as compared with pregnancies without an IUD in place, the risk of SAB is still lower than if the IUD is left in place.4 Additional risks of continuing a pregnancy with an IUD in place include increased risks of preterm labor, chorioamnionitis, and septic abortion.4,30
Complications of subdermal implant insertion
After insertion of the implant, women usually experience temporary bruising and soreness at the insertion site. Less than 1% of women develop an infection or hematoma.17 There is a low risk of nerve damage if the implant is inserted too deeply.15 Removal of the subdermal implant is recommended if pregnancy occurs.15
CASE DECISIONS › Jenny has been using oral contraceptive pills, but not regularly. You suggest that LARC may be a better option and counsel her that if she does choose an IUD or the implant, it is likely that her menses will change. You provide information and reassurance that LARC is safe to use in adolescents. Jenny says she would like to try an implant. Six months later, Jenny returns and says the implant is working well. She has some irregular bleeding, but it is not bothersome.