Name Info Provider Link
free resource BioMed Central https://bmcpregnancychildbirth.biomedcentral.com/articles/10.1186/1471-2393-12-63
Pain free resource MedlinePlus Health Information https://medlineplus.gov/pain.html
free resource PubMed Central https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22748068/
free resource Europe PubMed Central https://europepmc.org/abstract/MED/22748068