Effacement can only be detected with a vaginal exam, so you won’t be able to feel it happening. However, if you start to experience other early signs of labour, the process of effacement has most likely started. These signs might include:
Contractions
Feeling sick
Unusual backache or period-like cramping
Increased pressure on the pelvis
A trickle or gush of fluid from your vagina (waters breaking)
A pink gooey vaginal discharge (the mucus plug).