What is LARC?

“LARC” stands for long-acting reversible contraception

Two types of LARC methods available in the United States:

  • Intrauterine devices (IUDs)
  • Etonogestrel (ENG) implant

Two major advantages of LARC include:

  • LARC does not require ongoing effort for long-term and effective use
  • Rapid return to fertility after removal of the device

Types of LARC

Contraceptive implant
(about the size of a match stick)

Intrauterine device (IUD)
(about the size of a quarter)

Levonorgestrel (LNG) IUD

Mechanism of Action:

  • Prevent fertilization by changing amount and viscosity of cervical mucus, making it impenetrable to sperm

Evidence supports that LNG IUDs do not disrupt pregnancy and are not abortifacients

Most women ovulate normally, but experience diminished menstrual bleeding because of the local effect of levonorgestrel on the endometrium

99.8% effective; the one-year typical use failure rate is 0.2 per 100 women

Copper IUD

Mechanism of Action:

  • Inhibition of sperm migration
  • Change in transport speed of ovum
  • Damage to or destruction of the ovum

Evidence supports that the copper IUD does not disrupt pregnancy and is not an abortifacient

The most common adverse effects reported are abnormal bleeding and pain

99.2% effective; the one-year typical use failure rate is 0.8 per 100 women

Etonogestrel (ENG) implant

Mechanism of Action:

  • Primary: ovulation suppression
  • Additional: thickening of cervical mucus and alteration of the endometrial lining

After implant insertion, changes in bleeding patterns are common and include amenorrhea or infrequent, frequent, or prolonged bleeding

Placed subdermally in upper arm; size: 4cm x 2mm (comparable in size to a match stick)

99.9% effective; the one-year typical use failure rate is 0.05 per 100 women

Current LARC Methods

DescriptionBrand Name of MethodType of MethodFDA-Approved Duration of Use
Hormonal IUDKyleena®19.5 mg LNG IUD5 years
Liletta®52 mg LNG IUD4 years
Mirena®52 mg LNG IUD5 years
Skyla®13.5 mg LNG IUD3 years
Non-hormonal IUDParagard®Copper IUD10 years
Contraceptive ImplantNexplanon®68 mg ENG implant3 years