Parturients have the greatest risk of postdural puncture headache. use of a pencil-point needle, such as the 25 gauge Whitacre, has been associated with a lower incidence of PDPH. This observational study of 1009 obstetrical patients assessed possible factors related to the incidence of PDPH and other complications associated with spinal anesthesia using the 25 gauge Whitacre needle. The independent variables included procedure, maternal position at insertion, ease of insertion, intraoperative i.v. analgesia supplementation, use of intrathecal narcotics, parity and type of local anesthetic. Patients were followed daily during their hospitalization and questioned specifically about the presence of headache, its nature, onset and treatment. Two hundred and twenty-nine patients developed a headache postperatively but only 25 had postdural puncture headaches (overall incidence 2.5%). The PDPH typically presented on day 2 (median), range 1-4). Six patients (0.59%) required epidural blood patch. There were eight (0.8%) failed finals which were converted to general anesthesia. None of the factors evaluated were significant in predicting the occurrence of PDPH.