This study examined pain levels during the first stage of labor of 115 healthy primiparas. Pain was measured within 15 minutes of at least one routine pelvic examination from cervical dilation of 1 cm to 10 cm with the 100 mm Visual Analogue Scale (VAS) for both sensation and distress of pain. Both sensation and distress increased over time throughout the first stage of labor and paralleled each other except at cervical dilation of 10 cm. A unique change occurred in the level of pain during the first stage, especially in the sensation of pain. Sensation of pain was also significantly higher than the distress of pain at each centimeter of cervical dilation except during cervical dilation of 6 cm. The graph of sensation of pain levels suggests that it could be used to determine cervical dilation and minimize the number of pelvic examinations.