Study aim: Comparison of 22 gauge and 25 gauge spinal needles on the incidence, severity, and duration of post-dural puncture headache in women undergoing elective cesarean section Design: This controlled, parallel-group, double-blinded, randomized phase 3 trial will include 48 women. Randomization will use computer-generated block sequences with allocation concealment. Settings and conduct: The study will be conducted at the Department of Anesthesiology, Al-Habobi Hospital, Nasiriyah, Iraq. The anesthesiologist cannot be blinded, but participants and outcome assessors will be. The intervention group will receive spinal anesthesia with a 25-gauge needle, and the control group with a 22-gauge needle. All participants will receive standard postoperative analgesia and be monitored daily for five days. Participants/Inclusion and exclusion criteria: Inclusion criteria: Pregnant women aged 18-45 years, scheduled for elective cesarean section, ASA I–II, singleton pregnancy, and eligible for spinal anesthesia Exclusion criteria: History of headache or post-dural puncture headache, contraindications to spinal anesthesia, spinal deformity or prior spinal surgery, multiple pregnancy, BMI > 40 kg/m², and known neurological disorders. Intervention groups: All participants will receive standard perioperative care, and spinal anesthesia will be administered following a standardized protocol. They will be randomly assigned to one of two groups: Group A will receive spinal anesthesia using a 22-gauge needle, and Group B using a 25-gauge needle. Main outcome variables: Primary outcome: Incidence of post-dural puncture headache within five days. Secondary outcomes: Post-dural puncture headache severity, onset time of post-dural puncture headache, and procedure-related adverse effects within five days.