TMI CM question. ?

Alicia • Mommy of 4 boys..22, 19, 16, 14, and my sweet 4 year old daughter. EP 11/13, CP 03/16 PREGNANT WITH #6 ❤️❤️❤️❤️❤️❤️
How long after BD should you wait to check your CM?? Is the next morning accurate?? (7-8 hrs past last BD).