A comparative study published in BMC Anesthesiology illustrated that in parturients, mutation of COMTval158met gene results in elevated pain and anxiety during delivery. The influence of dexmedetomidine on anxiety of AA and GG genotypes is superior when compared to fentanyl. The mutation of COMTval158met gene does not influence dexmedetomidine's effectiveness in labor analgesia.  

Researchers examined impact of gene polymorphism on maternal pain and anxiety and on the analgesic and anxiety effectiveness of dexmedetomidine during childbirth. In total, 61 pregnant females, who were hospitalized were recruited and randomly segregated into: (i) F group: Received labor analgesia with ropivacaine in combination with fentanyl, and (ii) D groups: Received labor analgesia with ropivacaine in combination with dexmedetomidine.

Prior to and following labor analgesia, the genotype of catechol oxymethyltransferase (COMT) in the blood from F and D groups was assessed. Analysis of the situation of labor anxiety and analgesia was done. The association between analgesia, labor anxiety, and COMT polymorphism was examined. Among 61 participants, there were 30 females having wild homozygotes (GG) of COMT, 22 females having mutant heterozygotes (GA), and nine females having mutant homozygotes (AA).

Notably, mutation rate of allele A was found to be 23.77%. Compared to GG and GA genotypes, the AA genotype exhibited considerably greater anxiety trait score, anxiety status score, and pain score.

For management of labor anxiety, a profound inter-group difference was noted in the effectiveness of AA and GG genotypes. For managing delivery anxiety, the effectiveness of group D was better than group F.

There was no notable difference in: (i) anxiety scores between study groups in GA genotypes; (ii) pain between the study groups in GG, AA, and GA genotypes, and (iii) anxiety and pain scores between GG, AA, and GA genotypes in group D. A remarkable difference was noted in pain scores among GG, AA, and GA genotypes in group F. However, no considerable difference in anxiety was witnessed.