The effect of interpregnancy interval (I.PI) on birth weight and gestational age of infant was investigated in this prospective study among 250 post delivery women at Basrah Maternity and Child Hospital from the period of 1st December 1999 to 1st September 2000. Seventy five (30%) were found to have I.P.I. < 6 months, 84 (33.6%) of 6-12 months and 91 (36.4%) were found to have >12 months. Preterm rate in study group was 18/250(7.2%) with a high incidence among women with short I.P.I (16%) in comparison to other two groups, this difference was statistically significant. Small for gestational age (S.G.A) were 15/250 (6%) with a significant association among short I.P.I (12%). Women with short I.P.I were younger (21-30) years (56%), of low parity (p1-2) (56%) while high parity group (p5-6) have long I.P.I (17.5%). Women with short I.P.I were of low social class, (40%) of women with <6 months I.P.I. were illiterate. It can be concluded that short I.P.I (<6months) was associated with a significant increase risk of preterm labour and S.G.A. This risk should be taken into account when planning a new pregnancy