Ay, mucus plug at 37 weeks is possible pero hindi automatic sign of active labor agad, mama! You can lose it days or even weeks pa before actual labor starts, kaya hindi mo kailangan mag-panic, but definitely best to confirm with your OB kung ano exactly ang nakita mo, lalo na kung may bleeding or unusual discharge, para ma-monitor lang niya. Good luck sa buntis mo, you're almost there na!