Background: A brassiere is an article of clothing that covers, supports, and elevates the breasts, it comes in different sizes. Brassiere size has been associated with pectoral girdle myalgia (PGM).

Objectives of the study: To determine the prevalence of PGM in Nigerian women and investigated its association with brassiere size, number of children breastfed and working posture.

Methods: A total of 291 females (aged between 15 and 50 years) completed a 31-item closed-ended self-administered questionnaire, which was self-developed using a 6-man discussion group. It collected information on bio-data, prevalence of PGM and brassiere sizes as reported by the participants. The assumed actual brassiere sizes of the subjects were also measured by the investigators. Chi - Square was used to determine the association between occurrence of PGM and congruent versus incongruent brassiere sizes.

Results: History of PGM (in the last 12 months) among the 291 respondents was 45.4%. Contrary to findings in previous studies, the association between PGM and congruency of brassiere sizes was not significant (Chi-Square = 0.14, p = 0.710) in this study. There was a significant difference in the occurrence of PGM between the respondents who worked with elevated arm and those who did not. Fifty six (44%) of the respondents attributed pain to use of wrong brassiere size and 242 (87%) had relief after taking off their brassiere.

Conclusion: Pectoral girdle myalgia, although ignored, was common among the respondents. Also PGM was not associated with congruency of brassiere sizes in this study. However, we found a work-related item that had a significant association with the development of PGM. More studies are needed to further explore this finding.

Implications:   Ruling out the possibility of PGM in the treatment of cervical pathology may enhance management and reduce treatment period.