chicks and ducklings keep dying 3-4 days before hatching??

[BlossomR]

so ive hatched a lot of ducklings and chicks but recently both chicks and ducklings keep dying 3-4 days before hatching. its very sad and frustrating... do you have any idea why this is happening?

 

[Redemption]

so ive hatched a lot of ducklings and chicks but recently both chicks and ducklings keep dying 3-4 days before hatching. its very sad and frustrating... do you have any idea why this is happening?

Going to need more information....

What kind of incubator?
whats the temp and humidity say?
Have you checked it against another thermometer/hydrometer?
Is your incubator placed where if can be exposed to extreme temperature shifts?
is temp going above 102?
are you verifying movement prior to lockdown?