Preterm birth is more common in Afro Caribbean women. Previous research and management rarely stratifies by ethnicity. Interventions do not always take aetiology into account. We evaluated the risk factors by ethnicity in women referred to 15 preterm clinics in the UK over 3 years. Women were divided into European, Afro Caribbean and other groups. PTB rates <34 weeks gestation, and miscarriage rates <24/40 were compared. Risk factors for referral were compared by ethnicity.

Overall 2769 high risk women were analysed from a prospectively collected dedicated online database (with risk factor for preterm birth), and following consent: 1833 (66%) European (E), 656 (24%) Afro-Caribbean (AC) and 280 (10%) other [not analysed here]. PTB rates < 34 weeks were significantly lower in the E vs AC groups (6 vs 9%, Chisquare 7.34, p < 0.01), as were late miscarriage rates (1 vs 3%, Chisquare 14.9, p < 0.001). The groups had similar rates of previous spontaneous PTB (35 vs 38%, chisquare = NS) and current twins (3 vs 4%, chisquare = NS.) Women of European origin were more likely to have cervical surgery as a risk factor (46 vs 8%, Chisquare 3012, p < 0.0001), and less likely to present with a short cervix (9 vs 15%, Chisquare = 15, p < 0.001).

In high risk women presenting to a preterm clinic, ethnicity is related to risk. Some of these differences maybe explained by the criteria for referral which differ by ethnicity. Both management strategies and further research in preterm birth should take ethnicity and aetiology into account.