Self-reported confidence and anxiety helped predict labor pain and epidural local anesthetic use.  (Image source: Thinkstock)

Self-reported confidence and anxiety helped predict labor pain and epidural local anesthetic use. (Image source: Thinkstock)

Labor is the process of childbirth, from the start of uterine contractions to the delivery of the fetus and placenta. Labor hurts, of course, and the intensity of labor pain increases over the course of labor. Nevertheless, women experience pain differently.  Can we understand this variability?

Dr. Brendan Carvalho, Department of Anesthesia, Stanford University School of Medicine, Stanford, California, and colleagues measured the key psychological characteristics of fear of pain (via the self-administered Fear of Pain Questionnaire III [FPQ III], anxiety (using the Anxiety Sensitivity Index [ASI] written questionnaire), pain catastrophizing (via a Pain Catastrophizing Scale [PCS]) and personality traits (using the 48-question written Eysenck Personality Questionnaire – Short Scale [EPQR-S], and 3 scaled ratings of anxiety, confidence and analgesic expectations prior to the onset of labor in order to determine whether these tests would predict pain, analgesic use, and analgesic satisfaction during labor.  The results of this analysis are published in this month’s issue of Anesthesia & Analgesia in the article titled “A Prospective Observational Study Evaluating the Ability of Pre-Labor Psychological Tests to Predict Labor Pain, Epidural Analgesic Consumption and Maternal Satisfaction.”

Thirty-nine women, all of whom received epidural analgesia and underwent vaginal delivery, were enrolled in the study.  Median time from labor onset to epidural request was almost 5 hours (295 minutes). The median duration time of labor was about 11 hours (676 minutes).  Median maternal satisfaction with labor (0-100 scale, recorded immediately after labor) was 92.

Labor pain, epidural local anesthetic consumption, and time to epidural analgesia request were all predicted by the psychological characteristics of fear of pain, anxiety, pain catastrophizing, and personality traits.  Study results suggest that the Anxiety Sensitivity Index may help to prospectively predict the extent of labor pain and need for epidural local anesthetic use.  The Anxiety Sensitivity Index was included in the final multivariate linear regression model. Neither the Fear of Pain Questionnaire nor the Pain Catastrophizing Scale were included in the final model.

This is a preliminary result, and further study is necessary to determine whether the Anxiety Sensitivity Index is a better predictor of labor pain and epidural local anesthetic use than Fear of Pain Questionnaire or the Pain Catastrophizing Scale. Interestingly, pain catastrophizing did not predict pain, but it did correlate with epidural local anesthetic use.

The Eysenck personality traits assessed via the Eysenck Personality Questionnaire – Short Form were psychoticism, extroversion, neuroticism, and lying. Among these, only lying contributed to the model predicting time to request for epidural analgesia. Extroversion and psychoticism both contributed to the model predicting the area under the curve of labor pain over time.  Self-reported confidence and anxiety also contributed to the multivariate linear regression model of the area under the curve of labor pain over time, as well as the model of epidural local anesthetic use.  Anxiety and analgesic expectations contributed to predicting time to epidural analgesia request.

While surveys are useful, we point out that there is a simple two question survey that provides a great deal of information, and takes almost no time to administer:

  1. How are you doing?
  2. Are you in pain?