Hay naku mama, at 39 weeks na kayo, mas safe na talaga i-check agad with your OB kasi ang yellowish discharge especially pag basa-basa ang panty could mean a few things, could be normal increased discharge na malapit na mag-labor, or kailangan ninyong i-rule out ang infection or other things na importante i-monitor ngayon. One of my mum friends thought ganyan din siya, tapos ang OB agad lang nag-check for signs ng labor or infection, so better safe than sorry sa ganitong stage na! Bilisan ninyo ang pag-contact sa clinic, especially if may weird smell pa or itchy siya, para peace of mind ninyo bago mag-deliver.