I would think they are about to give birth.

Things to do before birth

1. Purchase a 5-10 gallon glass aquarium

2. Purchase a heater rated for your tank size

3. Purchase a air pump and airline tubing rated for your tank size

4. Purchase a sponge filter rated for your tank size

5. Purchase a strip light or LED light

6. Setup tank

7. Place females in the tank

8. After birth remove females and feed fry freshly hatched artemia for about three weeks

9. after the three weeks feed the fry crushed flake food

10. once the fry are big enought place them in the community tank