Most doctors and pregnant women would say they feel more at ease when the baby is moving regularly.
Feeling Baby Move: Weeks 18-21 of Pregnancy
Research About Baby's Movements
7 Interesting Facts About Baby Kicks During Pregnancy
What if I haven't felt my baby move for a while?
Baby movement in the womb, Pregnancy articles & support
Important Facts You Need to Know About Baby Kicking
Quickening: When Can You Feel Baby Move and Kick?
When & How to Do Kick Counts
Why Does My Baby Move More at Night in the Womb? - The Pulse