Real-World Live Birth Rates after Vasectomy: Data from the National Survey of Family Growth

Vasectomy is considered the gold standard for permanent male contraception, with guideline-reported failure rates of 1:2,000. However, these estimates are based on cohorts that may not reflect the evolution of surgical techniques and changes to provider mix. Contemporary incidence of unintended pregnancies after vasectomy remain unclear.

We estimated vasectomy failure rates using data from the National Survey of Family Growth, a Centers for Disease Control and Prevention-sponsored survey measuring reproductive health in the United States population. We extracted data from four survey waves of families who underwent a household vasectomy. Pregnancy rates were analyzed using Kaplan-Meier curves and multivariable Cox proportional-hazards models to assess the impact of demographic factors on pregnancy rates post-vasectomy.

The 829 male and 1,172 female participants reported a household vasectomy. The pregnancy rate after vasectomy from all eligible male respondents was 1.92% at 1 year, 3.52% at 5 years, and 3.75% at 10 years. From female survey data, the 1-year pregnancy rate in married couples after vasectomy was 0.57% at 1 year, 1.82% at 5 years, and 2.41% at 10 years. Multivariate analysis of male respondents showed younger respondents (hazard ratio [HR]: 14.04, 95% confidence interval [CI]: 2.37-83.20, p<0.01) was associated with higher unintended pregnancy after vasectomy while higher education status was associated with lower rates of post-vasectomy pregnancy (HR: 0.19, 95% CI: 0.04-0.91, p=0.04).

These data suggests that there may be nontrivial pregnancy rates after vasectomy with variation based on patient demographics. Further research is necessary to understand technical or patient related factors to lower unwanted pregnancies.