What are the efficacy rates of tubal ligation (tubal sterilization) compared to progesterone-only options (e.g. norethindrone (norethindrone) or medroxyprogesterone acetate (medroxyprogesterone acetate)) for preventing pregnancy, and what are the complication rates for pregnancies occurring after uterine ablation?

Contraceptive Efficacy: Tubal Ligation vs Progesterone-Only Methods and Pregnancy Complications After Endometrial Ablation

Efficacy Comparison

Tubal ligation is substantially more effective than progesterone-only contraceptives, with a first-year failure rate of 0.5% compared to 0.3-5% for progesterone-only options. 1, 2, 3

Tubal Sterilization Efficacy

• First-year typical use failure rate: 0.5 per 100 women 1
• Immediate contraceptive protection after laparoscopic and abdominal approaches (no backup method needed) 1
• Long-term cumulative failure rates may be higher than historically reported, particularly in younger women 4
• If pregnancy occurs after tubal ligation, there is a 30-80% chance it will be ectopic 4

Progesterone-Only Contraceptive Efficacy

Medroxyprogesterone Acetate (Depo-Provera) Injectable:

• Perfect use failure rate: 0.3% 2
• Typical use failure rate: 0.3% (same as perfect use due to provider administration) 2
• Requires reinjection every 13 weeks; effectiveness depends entirely on patient compliance with this schedule 2

Norethindrone (Progestin-Only Pills):

• Perfect use failure rate: 0.5% 3
• Typical use failure rate: 5% (due to late or omitted pills) 3
• Significantly more user-dependent than injectable or surgical methods 3

Key Efficacy Distinctions

• Tubal ligation provides permanent, immediate protection (except hysteroscopic methods requiring 3-month confirmation) 1
• Injectable medroxyprogesterone matches tubal ligation efficacy (0.3% vs 0.5%) but requires strict adherence to quarterly injections 2
• Oral norethindrone has 10-fold higher typical failure rate (5%) compared to tubal ligation due to user error 3

Pregnancy Complications After Endometrial Ablation

Pregnancy after endometrial ablation carries severe, life-threatening risks including uterine rupture, placenta accreta spectrum disorders, and maternal death. 5, 6

Complication Rates and Risks

Critical complications documented:

• Uterine rupture can occur as early as 24 weeks gestation, resulting in maternal death from massive hemorrhage 6
• Placenta increta/accreta requiring emergency hysterectomy has been reported 6
• Pregnancy after endometrial ablation is "not a rare occurrence, regardless of which technique is used" 6

Clinical Context

• Endometrial ablation is not an effective contraceptive method despite destroying endometrial tissue 5, 6
• Complications occur whether pregnancy is continued or terminated 6
• Concomitant tubal sterilization should be strongly considered at the time of endometrial ablation 6
• Women declining sterilization at ablation must use highly effective contraception 6

Specific Documented Outcomes

• One case: 25-year-old woman died at 29 from uterine rupture at 24 weeks, 5 years post-ablation (no prior uterine surgery) 6
• Another case: 34-year-old required emergency hysterectomy for placenta increta during pregnancy termination less than 1 year post-ablation 6

Clinical Decision Algorithm

For permanent contraception:

1. Tubal ligation (0.5% failure) provides immediate, permanent protection 1
2. Injectable medroxyprogesterone (0.3% failure) matches surgical efficacy if quarterly compliance maintained 2
3. Oral norethindrone (5% typical failure) should be reserved for women who cannot use other methods 3

For women undergoing endometrial ablation:

• Mandatory contraceptive counseling is essential given life-threatening pregnancy risks 6
• Offer concurrent tubal sterilization at time of ablation 6
• If sterilization declined, prescribe long-acting reversible contraception or injectable medroxyprogesterone 2, 6

Important Caveats

• Younger women (<30 years) have higher tubal ligation failure rates and regret rates (1-26%) 1, 4
• Tubal ligation does not protect against STIs; condom use remains necessary for STI/HIV risk 1
• The American Urological Association notes vasectomy is equally effective, simpler, safer, and less expensive than tubal ligation 1