Does It Matter If You're Black or White: Relationship Between Race/Ethnicity and Fecundability in Intrauterine Insemination Cycles

Abstract

Previous studies have found significant disparities in ART pregnancy rates by race and ethnicity with non-Hispanic whites having the highest pregnancy rates. There is a paucity of data regarding race and ethnicity in patients undergoing intrauterine insemination (IUI). One study found lower pregnancy rates in Asian patients compared to white patients undergoing IUI. To better counsel our patients, we sought to evaluate the effect of race and ethnicity on fecundability in IUI cycles. To evaluate the effects of female race/ethnicity on pregnancy rates with IUI treatment. This study was a retrospective chart review of IUI cycles performed July 2007 to June 2010 at a university-based infertility clinic. Medication used for ovulation induction or augmentation was noted. Charts were reviewed for confounding factors influencing pregnancy rates. Race/ethnicity was self-reported on a written intake form at patient's initial visit. Caucasians were sub-classified into Hispanic whites and non-Hispanic whites. Cycles were excluded if race/ethnicity was not reported. The primary outcome was positive pregnancy test per cycle. We calculated risk ratios (RR) and 95% confidence intervals (95% CI) using a generalized estimating equation method to estimate Poisson regression models with robust standard errors to account for repeated measures in the same patient. Of the 1,169 IUI cycles performed, 36 were excluded with no ethnicity reported, leaving 1,133 IUI cycles for analysis on 411 women. See Table 1 for results. Pregnancy rates overall were 13.4%. Average female patient age was 32.6 ± 5.3 years old. Results were adjusted for the following confounding factors: body mass index, total motile sperm count, infertility duration, infertility diagnosis, sperm source, and medications. IUI cycles among Hispanics were more likely to result in a pregnancy compared to IUI cycles among non-Hispanic whites. Controlling for age strengthens the association between Hispanic ethnicity and pregnancy. The pregnancy rates for American Indians and African Americans did not differ statistically from non-Hispanic whites. Contrary to previous studies, the pregnancy rates for Asian patients were no different than non-Hispanic whites.Tabled 1ResultsRace/Ethnicity# CyclesPregnancies (%)RR95% CINon-Hispanic White881118 (13.4%)1.00ReferenceAmerican Indian706 (8.6%)0.590.26-1.37Hispanic White5712 (21.1%)1.811.16-2.82Asian8111 (13.6%)1.120.62-2.01African American445 (11.4%)0.930.35-2.46 Open table in a new tab This study found no statistically significant difference in pregnancy rates for American Indians, Blacks, or Asians. Higher pregnancy rates were found in Hispanic females undergoing IUI treatment when compared to non-Hispanic whites. The reasons for this difference are unclear and deserve further prospective study. This is the first study evaluating effects of race/ethnicity on all women undergoing IUI, regardless of diagnosis or medication used.