You are ready to add to your chicken flock. Your rooster is raring to go. Your broody hen is ready to become a mother. All the conditions seem just right. But 21 days pass and no new chicks make an appearance. What happened?
There are ways to determine if your chicks have died in the egg or are still viable throughout the incubation process. By keeping an eye on the eggs during this time, most of the guesswork surrounding whether or not you should expect to have new members of your flock within those three weeks should decrease significantly.
There are many reasons chicks die in the egg, and determining the cause of their demise could be helpful in successful future hatches if the reason they failed is preventable.
How to Tell if an Egg Is Alive or Dead
To determine the viability of your eggs, candling them periodically throughout the process will let you know if the chick is still alive or if it has died at some point during incubation.
What Is Candling, and Is it Safe?
Candling is the process of holding the egg to a light source to determine whether or not the egg is still fertile. You can purchase devices explicitly made for candling, or you can make your own with a few materials and simple steps.
With your device in hand, in a dark room, with the large end of the egg up, the light will shine on the egg, allowing you to get a glimpse of the development taking place inside the shell.
As fertilized eggs are incredibly fragile for the first four to seven days of incubation, it is not recommended to begin candling too early to prevent damaging the embryo. Even once it is safe to start candling your eggs, you want to be very careful when handling them, and you do not want to candle them too often.
Viable embryos will quickly respond to the light from candling, while embryos that take more than 30 seconds to respond are more than likely sick or dying. If they are sluggish or do not respond, they should not be returned to the nest.
During this process, you will also be better able to see if an egg is cracked, something you might not notice with the naked eye. While it is recommended to discard cracked eggs, later, we will look into how you can attempt to repair and save a cracked egg if the embryo is still alive.
As the incubation period progresses, knowing what a healthy embryo should look like at different periods will let you know whether or not your chick has died in the egg.

Days 4-7
Again, you do not want to handle an egg before day 4, and it is advisable to wait until at least day 7 to ensure you allow the embryo time to set.
A viable embryo will look like a dark spot and have veins spidering out from it. It should also show movement within seconds of being candled.
Days 14-16
There will not be much room left inside the egg at this incubation stage, as the developing chick will have taken up most of the space. The area not filled by the chick will be an air pocket.
You should also detect movement from the chick inside the egg, which will be a good sign that it is still on track to hatch.
Day 18
This is the absolute last day you should candle your eggs, as the chicks are now preparing to hatch. If they are still alive, their necks should be turned up toward the top of the egg so that, on hatching day, they will be able to peck their way out of the shell.
You should also be able to hear a faint peep in addition to seeing movement.
My Egg Does Not Look Like it Should When Candled
If the embryo does not look as suggested and no movement is detected during the incubation period, it has probably died inside the egg.
Your embryo is probably not viable if:
- In the earliest stages of development, it appears like a small dark circle surrounded by a dark ring.
- Though harder to detect, there is no movement in the later stages of development, or the embryo appears to be surrounded by a dark ring.
Why Did My Chick Die in the Egg?
There is a myriad of things that could cause a chick to die before it is hatched. Some of the causes are preventable, while others are simply nature at work.
If you can detect a reason for the embryo’s death, hopefully, you will be able to use that information to prevent future pre-hatching deaths.
Typically, the death of an embryo will occur at the beginning of the incubation process, usually before candling the egg, or it will occur within the last couple of days of the incubation process.
Early Deaths
If it occurs at the beginning of the process, it can usually be attributed to some sort of deficiency in the embryo. The most common deficiencies found in early embryonic deaths are:
- Vitamin A
- Vitamin D
- Vitamin E
- Iron
- Copper
Because the deaths occur so early on, they are challenging to detect.
Late Deaths
Deaths that occur in the later stages of development can often be contributed to:
- Lack of ability to properly position itself to hatch.
- Lack of ability to breathe air.
- Could not correctly absorb yolk sack
- Deformity
Recording for the Future
It is suggested that you keep a record of the mortality of your eggs. If they do not hatch, note the approximate day they died. Also, by candling or opening the egg after it does not hatch, see if you can determine the cause of the chick’s death.
This process will help you with future hatches.
Another Important Factor to Consider
If you have a high mortality rate in your hatch, take a look at the health of the chicks’ parents. The parents could be the cause for the high mortality rate of your chicks if:
- They are not receiving enough nutrition.
- They are not receiving the right kind of nutrition.
- They are sick.
- They are carrying parasites.
- They are not mature enough to ensure fertility
If any of these factors appear genuine for your rooster or hen, then it is highly suggested that you care for their health before trying for more chicks. Otherwise, you can expect the same results.
If a Chicken’s Egg Is Cracked, Will it Still Hatch?

When candling your eggs, if you notice they are cracked, but the embryo still appears to be viable, you are now faced with a decision: remove the egg from the nest or try to repair it.
The issue with attempting to hatch a cracked egg is that bacteria will enter the egg VERY quickly, which will ultimately cause the chick to die. If you believe you have caught the problem in time, you can repair the egg to see if the chick will hatch.
How to Repair a Cracked Hatching Egg
Generally speaking, repairing a cracked egg is not recommended unless you know precisely when the egg became damaged. Since bacteria enters the egg quickly once it is cracked, the odds of the chick living until it is hatched are negligible even if you repair the crack.
If you decide to go ahead and try to save the egg, there are a few recommendations as to how to reseal the egg, and there does not appear to be one “correct” method.
Most suggest carefully using a mild disinfectant to wipe away any bacteria on the egg’s surface before repairing it.
Once cleaned, some of the ways to attempt to reseal the cracked egg include:
- Dripping candle wax on the cracks ONLY, not over the entire egg.
- Using a couple of coats of clear nail polish to paint over the cracks.
- Cover the cracks with white glue and smooth it out with your fingers.
After candling the egg in a day or two, allow the chick to try to hatch if the embryo still appears viable. If the embryo is dead, remove it from the nest.
Wrapping Up
The process of incubating eggs in the hopes of producing healthy chicks is a delicate process mainly left up to chance. Ensure the parents are healthy before the hen lays her brood and do all you can to keep the nest safe during the incubation period to give your potential chicks the best odds.
Candling the chicks at various points during incubation will allow you to determine if the egg is still viable or not. It can also alert you to cracks in the shell, allowing you to decide whether or not you want to try to save that egg.
Determining when the chick died and the potential cause of the chick’s death can possibly help prevent a high mortality rate in the future.