how to tell if your female snake is pregnant
Questions About Snakes

How to Tell If Your Female Ball Python is Gravid (Pregnant)

Just because your ball python looks pregnant, that doesn’t make it so. Maybe she ate a big meal that she’s taking time to digest. Maybe she’s ill. Or, maybe your female is getting fat.

Only a female that has mated (fully locked) with a male can be gravid. Check for follicles developing in her tail end. These will become eggs. The snake’s colors will be brighter. She will seek out cool temperatures at first. Ovulation is an obvious sign, where the female swells up a lot.

The time this takes is variable. A female can wait a long time after mating to fertilize her eggs. Afterwards, the whole egg-laying process in ball pythons takes 50 days.

When is Ball Python Breeding Season?

Ball python breeding season occurs in the spring. This is when snakes of many species finish the process known as ‘brumation.’

Brumation is like hibernation but for reptiles. During this period, the snake is practically inactive. It can’t eat because it’s too cold for it to digest food. It will sit almost perfectly still, only coming out if the sun warms up a spot for it to sit in.

After this period comes breeding season for ball pythons. This applies both in the wild and in captivity. Breeders simulate the turning of the seasons by lowering the temperature in the snakes’ enclosures.

Unlike many other species, the breeding season for snakes is set in stone. The unique environmental cues of winter and spring put the snakes in the mood to mate. Without that ‘mood’, they won’t mate. So if it’s out of season, your ball python likely isn’t mating.

Has Your Ball Python Mated?

This might sound obvious. You wouldn’t think that your female would be pregnant if it hadn’t mated. But you may be mistaking something else for ball python mating behavior.

When you introduce the male and female, each will first be aggressive. They may then get to know each other, calming down, and the male will climb on top of the female. He then slithers from side to side for a while before reaching her head.

To an observer who isn’t familiar with snakes, this looks like mating. But it’s only the first step. The pair then have to go through the ‘cloacal kiss’ process, where the male wraps its tail around the female’s tail. This is also called ‘locking.’

Only then will they have mated. If they don’t go through this process, the female can’t be gravid. For more information, read our ball python breeding guide.

How Long Do Ball Pythons Stay Locked?

The cloacal kiss has to last for an appreciable period of time. If it doesn’t, the pair won’t have had time enough to mate. This can occur because:

  • Another male approaches and prevents the pair from mating (unlikely in captivity)
  • The female decides against mating

A couple of hours is the least amount of time you could expect. But the process of locking takes around 24 hours on average, and can last two full days. So, unless you noticed this happening, your ball pythons didn’t mate. So, your female can’t be gravid.

Signs That a Ball Python Female is Gravid

There are several signs to look out for when identifying that a ball python is gravid. To be clear, we aren’t only looking at post-ovulation signs here. We’re looking at signs of everything from when the female first starts developing follicles, to when she will lay her eggs.

In reality, the follicles aren’t fertilized before ovulation. They aren’t proper eggs yet, so the female isn’t, strictly speaking, pregnant with young. The term gravid is used to refer specifically to when the female has ovulated and is carrying actual eggs.

The issue is that signs are appearing long before this point which indicate she may be laying eggs this season. The following sections are all about these early signs, when the female is first developing her follicles.

ball python looks pregnant

Follicles are tiny lumps of tissue that will eventually become eggs. The male’s sperm fertilizes them. But before they’re ready for that, the female has to make them bigger and bigger. This leads to the signs below.

According to PLoS One, the best way to check whether a female has developed follicles, or has ovulated fully, is through ultrasound evaluation. You can head to a vet to have this done. But the following signs you can look for on your own.

Behavior Changes in Gravid Ball Python Females

The first signs you’ll see, long before you can spot any obvious eggs, is that the snake’s behavior changes. The female will seek the cooler end of the cage. They will also coil around their water bowl if they have one, which is a very common sign.

The science behind this isn’t well understood, but we can make a few guesses as to why this is. Eggs need to be kept at a constant temperature throughout incubation.

What’s likely is that the eggs need to be kept at a constant temperature, even at this stage. During this time, the female will stay inside its hide, if she has one, or at least avoid your heat source.

Another behavioral change you might spot is where the female lays inverted, exposing her belly. Again, this is likely to be related to temperature regulation. It isn’t a sure sign of eventual ovulation; not all females that lay inverted are gravid, but almost all gravid females will lay inverted.

What is Lumping Up in Gravid Ball Pythons?

Something else you’re likely to see is ‘lumping up.’ Contrary to what you might think, this isn’t where you start seeing the lumps of the follicles inside your female. This sign comes before that point.

Lumping up is something that happens while they’re wrapped around their water bowls (or similar features in their enclosure). It will look like your female has lots of lumps or kinks along its spine. It happens at the stage when they’re building their follicles, which will later become the eggs.

It’s unclear precisely what causes lumping up. It’s not to do with the follicles themselves, because the lumps appear all along the female’s body. But it’s a common sign all the same.

Color Changes in Gravid Ball Pythons

One of the most drastic changes is in the female’s color. This change comes before their pre-ovulation shed. If you didn’t know, females will have to shed before they ovulate (which is when the eggs are fully formed from the follicles).

It’s frequently the case that a snake’s colors will sharpen or fade before shedding and during the blue phase. But in gravid females, it’s especially noticeable. This change can easily be spotted around the head and neck.

Bear in mind that each of these signs appears in order. The first signs you’ll see are behavioral changes, and perhaps lumping up. Then, you’ll see the female’s color change. It’s only after these signs that you’ll notice the shape of the follicles inside the female.

Females can change color up to six weeks before they shed. This pre-ovulation shed is the last sign before ovulation occurs. It’s an integral part of the process, because the female needs to shed in order to accommodate the large eggs she’s carrying.

Unfortunately, not all females will do a pre-ovulation shed.

Do Ball Pythons Eat when Pregnant?

Ball pythons tend to avoid food when carrying eggs. This is a behavior that’s common to many animals of many different species.

You would think that a pregnant female of any species would need to keep its strength up. And while this is true, consider the alternative. How difficult would it be for the animal to hunt? How likely is it that the animal would itself be preyed on?

This is a difficult issue to balance. Snakes get around it by stocking up on food in advance. Both females and males eat prodigiously at the beginning of the breeding season, so that they can fight and produce eggs with no issues.

This is borne out in captivity, too. Gravid females tend to eschew food. This trend carries on if you allow the female to look after her clutch after oviposition (laying). During this time, she will continue to avoid food.

What Does a Gravid Ball Python Look Like?

The next stage is where the female is building its eggs. They will have developed the follicles long before this. The follicles are like the tiny seeds that the egg will grow from. But it’s only now that they get big enough to be obvious.

In the beginning, this may be difficult to spot. The best way to identify whether the female’s follicles are growing bigger is to handle her. Allow her to relax, and you can see and feel the follicles swelling under her skin. They sit around 2/3 of the way down her body.

It’s easy to mistake these lumps for a recently eaten meal. But if you handle the female while she isn’t digesting, there won’t be a meal to mistake them for.

At this point, the follicles aren’t tiny eggs. They’re like a hard lump of tissue. And before the female ovulates, you shouldn’t consider her ‘pregnant’ because these follicles haven’t been fertilized. It’s only later that this happens.

Why is this important? Because follicles can be reabsorbed by the female. She doesn’t need to create an egg from every follicle. She could make some, none, or all of them into eggs. So follicles don’t mean that the female will be laying eggs for sure.

how long are ball pythons pregnant?

What Ball Python Eggs Look Like

The next stage of the process is ovulation. This is where the follicles are fully developed, and the female uses the male’s sperm to fertilize them. Believe it or not, but this can take place several months after mating. The female holds onto the male’s sperm all that time.

Ovulation is where the follicles are released from the place they’re made, into the oviducts. This is where the eggs are fertilized. It’s here that calcium and other minerals from the shell that will go around the egg.

The building looks like the female is slightly larger than usual. But ovulation looks unusual, even worrying. If it weren’t related to breeding, you’d think that the swelling in the female’s tail was a sign of serious illness.

The eggs appear like large lumps in the female’s body, almost like she’s eaten several big meals. But what’s different is where these lumps appear. As you might imagine, they appear towards the female’s rear end, around two-thirds of the way along her body.

Signs That a Ball Python Has Ovulated

Ovulation is the first real step towards rearing a successful clutch. Before this point, it’s possible for the female to reabsorb the follicles, and not lay any eggs at all. But after ovulation, the female will be laying eggs soon. There are several signs that ovulation has occurred. These include:

  • The female’s belly becomes large, hard, and swollen. It looks like she has eaten a huge meal, and the skin of her belly becomes taut. This will be around ¾ of the way along her body, towards her tail.
  • The female seems unhappy. The changes that are occurring may be painful or stressful.
  • The female’s tail looks different. Most of it will be stretched and taut. But the tail tip will be shrunken and shriveled.
  • The female has pronounced ridges along her back. It looks like her spine is kinked upwards in several places. These lumps are the eggs.
  • The pre-lay shed. This is a separate shed to the pre-ovulation shed. The female will usually shed roughly three weeks after ovulation, and lay their eggs around thirty days later.

Another sign is a change in the female’s behavior. Rather than seeking out warmth, she will stay in the warm part of her enclosure. Again, this is to keep the eggs at a constant temperature.

How Long are Ball Pythons Pregnant?

The answer depends on what exactly you consider to be ‘pregnant’ (or gravid). The reproductive cycle of ball pythons is complicated, and ‘pregnancy’ doesn’t begin immediately after mating like it does in other animals.

The cycle begins at the beginning of the mating season. In response to environmental cues like warmer temperatures, the female will start developing her follicles. This process can take four to eight months.

It’s only once this is complete that the female can ovulate, because otherwise, the follicles wouldn’t be completely developed. The female can mate at any time during this process. She will then retain the male’s sperm to be used during ovulation.

When ovulation begins, it will take around 50 days before the eggs are laid (oviposition). Pre lay shed to laying ball python eggs takes thirty days. The eggs then take 60 days to hatch. The length of time before hatching depends on temperature.

What Is Oviposition in Snakes?

Oviposition is the scientific term for laying eggs. This term is used for all animals, from reptiles to insects and birds.

After your female lays her eggs, you have to incubate them. You’ll need an incubator, an egg box, and ideally a generator. It’s vital that you keep the temperature and humidity at a constant level for the eggs. This avoids birth defects.

When to Cut Ball Python Eggs

60 days after they’re laid, the eggs will hatch. But you can help them along by cutting the eggs. Cutting is where you make a small incision to help the snakes out of their eggs.

The snakes can do this for themselves, but if they’re a little too weak, they would die before they can. Done correctly, cutting increases clutch numbers.

This must be done at the right time. Wait for one of the snakes to crack a hole in their egg, and then do the same for the rest. This ensures that you do so at about the right time.