signs your gerbil is pregnant
Care Guide

How Do I Know My Gerbil is Pregnant? Gerbil Pregnancy Signs!

If your female gerbil has spent time around a male, there’s a chance she may be pregnant. Gerbils come into heat every four days, and almost always get pregnant the first time they mate.

The first sign of pregnant gerbil is an increased appetite, and steady weight gain. Towards the end of the pregnancy, your gerbil’s belly will look rounded and swollen. You may also notice nesting behavior, and a change in personality. Pregnant gerbils can become aggressive and nervous as their due date approaches.

In this guide, you’ll find out the age that gerbils can conceive, and learn about the main signs of pregnancy in gerbils. We’ll also explain what to do if you think your gerbil is pregnant.

Is My Gerbil Pregnant?

Like all other mammals, gerbils reproduce sexually. A male gerbil must mate with a female gerbil for her to become pregnant.

After intercourse, the male’s sperm fertilizes the female’s ova (egg cells), creating embryos. Each embryo develops into a baby, called a pup. An average gerbil litter contains 3 to 6 pups, but litters of up to 10 are possible.

Female gerbils don’t have a small monthly window in which to get pregnant. Instead, their eggs mature in response to mating. This is called spontaneous ovulation.

Female gerbils can get pregnant all year round. They go into heat and are fertile for four days at a time, with a 4-day break in between.

A gerbil’s chances of conception are good; they usually get pregnant the first time they mate. So, if your female gerbil has been around a male, she’s more likely to be pregnant than not.

Even baby gerbils can have pups of their own. Gerbils reach adulthood at around 6 months of age, but they can get pregnant much earlier than this.

According to Developmental Psychobiology, female gerbils can conceive at 9 weeks of age.

Gerbils are good at hiding their pregnancies. You’ll have to pay close attention to spot the signs that your gerbil is expecting.

Gerbil Pregnancy Signs

It’s often difficult to detect that a gerbil is pregnant. Throughout the majority of the pregnancy, your gerbil won’t look or act differently to normal. Some people don’t notice the pregnancy until they see a nest full of tiny gerbil pups.

A gerbil’s pregnancy is easiest to spot between one and three days before she gives birth. This is when the babies are largest, and the mother’s swollen belly becomes obvious. This is also when the mother experiences hormonal changes, causing pregnant gerbil behavior.

However, there are some subtle pregnancy signs that are present throughout gestation.

Pregnancy SymptomDescriptionStage of Pregnancy
Weight gainGerbils gain 1-3 grams per day while pregnant.Throughout the pregnancy. Weight gain will speed up as pregnancy progresses.
No longer matingGerbils come into heat and mate every 4 days. While pregnant, female gerbils stop mating completely.Throughout entire pregnancy.
Increased appetiteGerbils eat more during pregnancy.Throughout the pregnancy, but most noticeable in the last 2 weeks.
Change in body shapeDuring pregnancy, a gerbil’s belly becomes rounded. By the end of the pregnancy they will look pear-shaped.Most visible during last week of pregnancy.
Personality changesPregnant gerbils may seem more aggressive or nervous, especially when handled.Last week of pregnancy.
Nesting behaviorAs labor approaches, your gerbil will build a nest for the pups.Last 1-2 days of pregnancy.

According to Laboratory Animals, the average gerbil gestation lasts 24 to 26 days (3.5 to 4 weeks). But all gerbil pregnancies are different, and not all gerbils will display the same symptoms.

Can Gerbils Gain Weight While Pregnant?

Gerbils gain weight throughout their pregnancies. They will lose it again after giving birth and weaning their pups. The extra weight comes from:

  • The mass of the pups and the placenta
  • Water retention, important for creating amniotic fluid and an increased blood supply
  • Extra fat stores, which the mother will turn into milk for her young

Most pregnant gerbils will gain 1 to 3 grams per day throughout gestation. Weight gain is slow at first, but will speed up as the pregnancy progresses. It will be most noticeable in the last few days of pregnancy.

For most of the pregnancy, you won’t notice any weight gain by looking at your gerbil. To be certain, you’ll have to weigh her using a kitchen scale.

It’s also helpful to weigh your other gerbils at the same time. If they’re all gaining weight, it may be that you’re feeding them too much.

How Do I Know My Gerbil is Pregnant?

Do Gerbils Mate While Pregnant?

When female gerbils are not pregnant, they will come into heat 4 times per month. While in heat, female gerbils are fertile, and will mate several times a day (if there is a male around). You will know your gerbils are mating if:

  • The female presents herself to the male
  • The male mounts the female for several seconds, and the female allows it to happen
  • After parting, each gerbil grooms its genital region

Gerbils are in heat for four days, and then have a four-day break. The only reason that a female gerbil would not mate for an extended period of time is if she were pregnant.

While pregnant, female gerbils do not come into heat, so they don’t mate. Gerbil pregnancies last almost four weeks. If your gerbil has not mated for longer than a week, it’s likely she’s pregnant.

However, mating can be confused with dominance mounting. Gerbils can mount each other to assert dominance, and this can happen during pregnancy. That’s why an abstinence of mating behavior isn’t always a reliable indicator of pregnancy.

Do Pregnant Gerbils Need More Food?

Although it’s a myth that pregnant mothers should ‘eat for two’, some extra food is helpful during pregnancy.

If given the chance, gerbils will eat more than usual while they’re expecting. The extra calories, protein, and healthy fats will help their pups grow. It will also help the mother to build up her fat stores, essential for boosting her milk supply.

You may notice that your gerbil seems hungrier than usual if she’s pregnant. She may eat faster, or seem more food-motivated than she normally is. You may see her checking the food dish more often.

Another indicator of pregnancy is if the other gerbils living with her seem to be losing weight. This is a sign that the pregnant gerbil is eating more than her fair share. It’s a good idea to up your gerbils’ food allowance if you suspect that one is pregnant.

What Does a Pregnant Gerbil Look Like?

Usually, your gerbil will look slim and streamlined. Its body width should be approximately the same, from its neck down to its rump. However, if your gerbil is pregnant, its body will change shape as the babies grow.

During the first half of pregnancy (the first two weeks or so), your gerbil won’t look any different. This is because the pups are still small enough not to be noticeable from the outside.

The third trimester of a gerbil’s pregnancy is when her pregnancy becomes obvious by sight. In the final week or so, she will look a little rounder every day. In the last few days of pregnancy, she will look distinctly pear-shaped, with a swollen belly.

A bulge in your gerbil’s belly doesn’t always guarantee pregnancy. It can also be caused by certain medical conditions, such as:

  • A tumor or cyst
  • Heart failure (causing a buildup of fluid in the abdomen)
  • A bacterial infection
  • An impacted gut
  • Inflammation of the stomach (peritonitis). According to the Journal of Veterinary Science, peritonitis in gerbils can result in abdominal swelling, depression, and shortness of breath.

That’s why you should take your gerbil to a vet for a professional opinion. If pregnancy isn’t the cause, your gerbil may need medical treatment.

How Do Pregnant Gerbils Act?

During pregnancy, gerbils experience hormonal changes that help the babies grow. The two main pregnancy hormones are estrogen and progesterone. They have many important jobs, such as triggering the development of the fetuses’ organs.

But as well as helping the pregnancy progress, these hormonal changes can also alter your gerbil’s behavior. Pregnancy hormones can trigger gerbil mood swings and personality changes.

Throughout the first 2-3 weeks of pregnancy, your gerbil will probably behave normally. But as your gerbil gets closer to her due date, pregnant gerbil behavior will become more obvious.

You may notice that your gerbil seems more skittish and anxious than usual. This is because she’s more aware of danger. It’s an evolutionary defense mechanism designed to protect the babies from predators. 

Your gerbil may act aggressively, toward other gerbils or yourself. If you try to pick her up, she may attempt to escape your hand or bite you. Again, this is an evolutionary instinct that helps keep the babies safe.

pregnant gerbil behavior

Do Gerbils Build Nests When Pregnant?

Pregnant gerbil hormones are also responsible for nesting.

When gerbil pups are born, they can’t regulate their own body temperature straight away. They depend upon their mother building them a deep, warm nest to live in. If she didn’t do this, her babies might freeze to death.

So, once your gerbil senses that she’s about to give birth, she’ll start building a nest. She’ll collect the softest materials she can find, like paper towels, hay, and wood pulp substrate. She’ll chew them up and form them into a round nest with a hole in the middle.

If there is a wooden hide box in your gerbilarium, she may choose to build the nest inside it. Otherwise, she will build it right on top of the substrate, or inside a tunnel.

Nesting is one of the most obvious pregnancy gerbil behavior signs. If you notice nesting, it means that birth is imminent.

What To Do If a Gerbil Is Pregnant

If you suspect that your gerbil is pregnant, don’t worry. Looking after a pregnant gerbil isn’t hard, and they make naturally good mothers.

There are, however, some things you can do to help the pregnancy progress smoothly. This will ensure that the pups have the best possible start in life.

1/ Remove the Male Gerbil

If you know who the father is, separate him from the mother straight away. Gerbils instinctively mate immediately after giving birth. So, if you leave the two together, she’ll conceive a second litter straight away.

If you own more than two gerbils, you’ll need to figure out which one is male. You can do this by sexing your gerbils, or taking them to a veterinarian. Until you know which gerbil is male, keep them separated in individual enclosures.

The only way to safely leave male and female gerbils together is by having your male gerbil neutered. But many vets refuse to perform this operation.

This is because anesthetic can be risky for small animals. The operation is also extremely complex, as gerbils’ genitalia are so small.

2/ Schedule a Veterinary Checkup

Taking your pregnant gerbil to the vet is optional, but it’s a good protocol. As gerbil pregnancies are so hard to detect, it’s the only way to be certain.

The veterinarian will confirm your gerbil’s pregnancy, and estimate how far along she is. They’ll also check her overall health, and answer any questions you might have.

It’s a good idea to take your other gerbils for a checkup, too. This includes the male gerbil, and any other females he’s been in contact with.

The veterinarian can also sex all of your gerbils, to make sure there are no more rogue males. They’ll also check whether any of the other females are pregnant.

3/ Supplement Your Gerbil’s Diet

When a gerbil is pregnant, her appetite will increase. This is because she’ll need an extra supply of calories to help grow her babies. She’ll also need to build extra fat reserves to turn into milk for her pups.

This is a good time to start supplementing your gerbil’s diet with additional sources of fat and protein. For example:

  • Insects, such as mealworms and crickets
  • Nuts and seeds, such as pumpkin seeds and almonds
  • Small pieces of scrambled egg and hard cheese
  • Small pieces of plain boiled chicken 

Your gerbil may drink more during pregnancy, so be prepared to top up the water bottle more often. You should also attach another water bottle low to the ground, so that the babies can reach it.

4/ Provide Nesting Materials

A few days before giving birth, your gerbil will get the urge to make a nest. She will select the warmest, softest materials available to her. You can help by providing her with some extra comfortable bedding, such as:

  • Plain white tissues
  • Toilet paper or paper towels
  • Hay
  • Paper pulp bedding

Don’t use any cotton-like or synthetic materials. Stick to paper or wood-based products, as they’re safe for gerbils to digest.

Once your gerbil has built her nest, don’t touch it, or make any changes to the gerbilarium. This could cause unnecessary stress, as could handling your gerbil excessively while pregnant.

5/ Monitor the Pups Closely

A gerbil is at its most vulnerable during the first few weeks of life. Gerbil pups are born blind, deaf, and unable to regulate their own body temperature. They depend entirely on their mother.

The mother gerbil will need extra food and water during the first five weeks after giving birth. Ensure the cage is out of direct sunlight, and kept warm. A blanket over the cage can help block out harsh light or noise.

Check on the pups regularly. But don’t handle them until they’re a week old, unless they are in immediate danger.

6/ Separate the Pups

The pups will be weaned around 5 weeks of age. At this point, they can survive on their own. It’s safest to wait until 6-7 weeks before separating them from their mother.

Gerbils can reach sexual maturity as young as 8-9 weeks of age. So, you must separate the male and female gerbils by this point. Otherwise, you’ll end up with more gerbil babies.

If you want to keep the pups, split them into same-sex pairings or small groups. You’ll need a separate gerbilarium for each group. If you can’t keep the pups, you’ll have to find new homes for them.

The best thing to do with gerbil pups is to give them to a gerbil rescue center or shelter. For more information and guidance, take a look at our guide on what to do with unwanted gerbils