Objective The authors evaluated the differences in preterm birth rates in the setting of pre-eclampsia by gestational age (GA) at birth and between different racial/ethnic groups. Study Design This is a retrospective cohort study of all pregnant women delivered in California in 2006, separated into two cohorts: pre-eclampsia and no pre-eclampsia. Outcome data were tabulated by four GA groups (24–27, 28–31, 32–36 and 37–42 weeks) and stratified by race/ethnicity. Results Women with pre-eclampsia are at a significantly increased risk of delivering at earlier GAs as compared to women without pre-eclampsia at all GA groups analysed (p<0.001): 24–27 weeks, 0.4% vs 1.4%; 28–31 weeks, 0.8% vs 4.9%; and 32–36 weeks, 9.1% vs 28.2%. Preterm delivery rates in the setting of pre-eclampsia varied by race/ethnicity and were significantly lower in Latinas (p<0.001): 31.4% in Latinas, 37.2% in Caucasians, 38.2% in African Americans and 38.9% in Asians. Conclusion Although African American women without pre-eclampsia experience higher preterm birth rates than other racial/ethnic groups, this effect is not seen in African American women with pre-eclampsia. In the setting of pre-eclampsia, Latinas have fewer preterm births than other racial/ethnic groups.

Objective The authors evaluated the differences in twin preterm birth rates in the setting of pre-eclampsia by gestational age at birth and between different racial/ethnic groups. Study Design This is a retrospective cohort study of women pregnant with twins delivered in California in 2006, separated into two cohorts: pre-eclampsia and no pre-eclampsia. Outcome data were tabulated by four gestational age groups (24-27, 28-31, 32-36 and 37-42 weeks) and stratifi ed by race/ ethnicity. Results Women with pre-eclampsia are at a signifi cantly increased risk of delivering at 32-36 weeks as compared to women without pre-eclampsia (p<0.001): 61.4% vs 45.5%. Preterm delivery rates in the setting of pre-eclampsia varied by race/ethnicity and were signifi cantly higher in Caucasians and lower in Asians (p<0.001): 71.0% in Caucasians, 66.7% in African Americans, 67.0% in Latinas and 63.6% in Asians. Conclusion Women with twins who also have pre-eclampsia have 15.9% more preterm births. Although African American women without pre-eclampsia experience higher preterm birth rates than other racial/ethnic groups, this effect is not seen in African American women with pre-eclampsia. In the setting of pre-eclampsia, Caucasians have more and Asians have fewer preterm births than other racial/ethnic groups.