OBJECTIVE: To determine the frequency of preterm birth and to identify its aetiological factors in a rural set up hospital.

BACKGROUND: The rate of spontaneous preterm birth keep on rising and the exact cause is still unclear.Generalised approaches in screening for high risk status and interventions have failed to reduce preterm birth rates.Preterm birth presents a clinical dilemma due to it etiologic and pathophysiologic heterogeneities.

MATERIAL AND METHOD: This prospective, descriptive study was conducted in the Department of Gynaecology & Obstetrics at Baqai Medical University from January 2006 to December 2007.A total of 136 of cases of preterm labour were evaluated. Information regarding past history, present symptoms and obstetrical history was collected followed by detailed examination. Investigation was done including Hb%, total leukocyte count, platelet count, urine D/R (microscopy, culture and sensitivity), high vaginal swab (gram staining, culture and sensitivity), and pelvic ultrasound. Statistical analysis was performed using SPSS package for windows version 12.5.

RESULTS: Frequency of preterm birth was 7.5 % (elective preterm births and twin pregnancies were excluded).Out of 136 cases 56.6% were < 25 years of age, 30.1% were primigravidas, and 91.2% were unbooked cases, 25% had a past history of preterm birth, and 8.8% had past history of > one second trimester abortion. Cause is multifactorial in almost half of the cases. Anemia was the most common cause 45.2%.Othercauses include bacterial vaginosis

16.9%, systemic infection 13.2%, urinary tract infection abruptio placenta and pregnancy induced hypertension 11% each, and fetal anomaly 10.3%, cervical incompetence 3.7% and medical disorders 2.9%.Majority 88.2% had a vaginal birth. There were 74 (40%) perinatal deaths, out of which 41 were intra uterine deaths and 33 neonatal deaths.

CONCLUSION: Preterm labour and births are common in rural set up hospital. Anemia and infections are leading factors responsible. Late arrivals of patients to health care facility lead to adverse perinatal outcome. Education, provision of health care, prevention and treatment of risk factors is necessary for to reduce the incidence and adverse pregnancy outcome.