Name Info Provider Link
subscription/membership/fee required Elsevier Science https://linkinghub.elsevier.com/retrieve/pii/S0016-6480(11)00461-8
Pregnancy free resource MedlinePlus Health Information https://medlineplus.gov/pregnancy.html
subscription/membership/fee required ClinicalKey https://www.clinicalkey.com/content/playBy/pii?v=S0016-6480(11)00461-8