Contraception

LARC primacy, method selection & special populations

Field: Women's HealthCode: WH-01Updated: June 2026Reference: RANZCOG/FSRH C-Gyn 3 / UKMEC 2025

LARCs (IUDs & implant) are first-line for all ages — there is no nulliparity bar. Quick-start (starting any method on the day of the visit) is appropriate for most patients once pregnancy is reasonably excluded.

Tier 1 — LARC (first-line)

Hormonal IUDs (52 mg & 19.5 mg LNG): 5–8 years; the 52 mg device cuts bleeding by ~90% and is also first-line therapy for HMB.
Copper IUD: 5–10 years, hormone-free; doubles as emergency contraception up to 5 days; may increase bleeding.
Etonogestrel implant: 3 years, subdermal, GP-inserted; failure <0.1%.

Tier 2 — short-acting methods

COCP, progestogen-only pill, vaginal ring, patch: all ~9% typical-use failure — effectiveness depends heavily on adherence.
Depot medroxyprogesterone: ~6% typical-use failure; watch bone mineral density with long-term use; reversal can be slow.

MBS / PBS item numbers. IUD insertion and removal item numbers, and current PBS listings for LARC devices, change — confirm at mbsonline.gov.au and pbs.gov.au before billing or prescribing.

Special populations

Adolescents: LARC first-line; no minimum age; no parental consent needed if Gillick-competent; consider an STI screen at insertion.
Postpartum: progestogen-only methods from day 1; IUD from 6 weeks; combined hormonal methods from 6 weeks (breastfeeding) or 21 days (not breastfeeding, no VTE risk factors).
Perimenopause: continue contraception to 50 (hormonal) or 55 (non-hormonal); the hormonal IUD can double as the progestogen component of MHT.

Contraindications — UKMEC 3/4

Combined hormonal contraception: age >35 plus smoking, migraine with aura, active breast cancer, VTE history, uncontrolled hypertension.
Enzyme inducers (rifampicin, carbamazepine, phenytoin, St John's Wort) reduce combined hormonal efficacy.
IUDs avoided in active pelvic infection (treat first), current STI, confirmed or suspected pregnancy, or a distorted uterine cavity.

Emergency contraception

Copper IUD up to 5 days: most effective option, and can stay in for ongoing contraception.
Ulipristal up to 120 hours: more effective than levonorgestrel at higher BMI or later presentation; delay starting hormonal contraception for 5 days after.
Levonorgestrel up to 72 hours: available over the counter; less effective at higher BMI; restart usual contraception the same day.

Safety

New migraine with aura on combined hormonal contraception — stop immediately, this is an absolute contraindication.
Counsel on UKMEC category before starting any combined hormonal method in a patient with vascular or hepatic risk factors.
Confirm pregnancy status before IUD insertion or a quick-start initiation.

Red flags / refer

Significant pain or bleeding after IUD insertion → exclude perforation, expulsion or ectopic pregnancy.
Suspected IUD malposition → pelvic ultrasound and gynaecology review; don't attempt removal blind.
New heavy menstrual bleeding on a LARC, or symptoms not settling with the expected method → investigate, consider the hormonal IUD as therapy.

WH-01 v1.0 · Reviewed Jun 2026 · Review Jun 2027

For health-professional use. Framework: RANZCOG/FSRH C-Gyn 3 (2024), Family Planning Australia, UKMEC 2025. Quick reference only — exact device PBS status & MBS item numbers change. Verify at pbs.gov.au / mbsonline.gov.au.