Interpregnancy interval and the risk of preterm birth in Thrace, Greece.

Objective: To examine the influence of short interpregnancy interval on the prevalence of preterm birth in two, ethically different, Greek populations.

Study Design: We studied 652 urban Christian women and 578 rural, Romany, Muslim women who had had two consecutive, singleton pregnancies. We related the prevalence of preterm birth to the interpregnancy intervals (cut-off point, 6 months). Student's t-test, x(2)-test and relative risk estimation were used.

Results: Preterm birth and interpregnancy intervals less than 6 months occurred more often among Muslims than Christians. Among Muslims, an interval of <6 months was associated with greater prevalence of preterm birth (16% versus 7.3%, P=0.013, RR=2.4 and 95% C.I. 1.3-4.7). Christians did not demonstrate a similar relationship.

Conclusions: A short interpregnancy interval seems to be a risk factor for preterm birth in the population of rural, Romany, Muslim women.