Guinea Pig Pregnancy Week-by-Week Guide for Development & Care

Determine if your Guinea pig is pregnant and how far along she is with this week-by-week development and care guide.

Published April 21, 2023
Beautiful high resolution image of a cute guinea pig mom nursing her three newborns pups

Guinea pigs all look like plump, furry potatoes, but if your female Guinea pig looks especially round, you might wonder if she is pregnant. You can figure out if your Guinea pig is expecting and what stage of her pregnancy she's in based on both physical and behavioral clues. Use our Guinea pig pregnancy guide (complete with week-by-week changes and potential complications to be aware of!) to prepare for your new litter of furry little potatoes.

How Long Are Guinea Pigs Pregnant?

Guinea pigs are pregnant for an average of 65 days. Of course, just like humans, some can give birth a little before this date, and others might be slightly late. Experts say cavy pregnancies should last between 59 and 72 days.

Fast Fact

Guinea pigs can have up to five litters a year! The average litter size is four, but they can have anywhere between one and eight babies per litter.

Signs of Guinea Pig Pregnancy

Not sure if your Guinea pig is pregnant or just … round? It can be difficult to know if your pig has buns in their oven within the early stages of pregnancy, but as the babies develop, you'll notice these signs:

  • Foul smell (from the male's urine sprayed on the female after mating)
  • Increase in appetite and thirst
  • Visibly growing belly
  • Weight gain
  • Palpable "lumps" within the abdomen
Fast Fact

Baby Guinea pigs are called "pups." How cute is that?!

The best way to confirm whether or not your Guinea pig is pregnant is by taking them to the vet. They can do an exam and perform an ultrasound to visualize the pups, just as a human doctor would with a pregnant person.

Week-by-Week Pregnancy Development Guide

In order to plan for the arrival of little Guinea pig pups, it's helpful to estimate how far along your mamma pig is. Use this week-by-week Guinea pig pregnancy guide to determine where she falls and make sure your Guinea pig is getting the appropriate care based on her stage.

Weeks 1 - 3

The babies are just beginning to develop within the first few weeks of pregnancy. If you suspect your Guinea pig is pregnant, switch out her regular hay with Alfalfa hay. Alfalfa is more nutrient-dense than other hay types and has the extra calcium and protein your mamma needs to grow healthy pups. Make sure she gets plenty of calcium-rich veggies, such as broccoli, spinach, and kale, too.

Weeks 4 - 6

The Guinea pig pups are visible on ultrasound after the 21-day mark, so your vet can use the ultrasound to see how the babies are developing. As the fetuses grow, your mamma pig will eat more and gain weight. Get a small scale and monitor her weight to make sure she's gaining at a safe rate (gaining weight too rapidly can lead to complications) and not losing any weight.

Weeks 7 - 9

At the beginning of the final stage of pregnancy, you should definitely feel and even see the babies moving within your Guinea pig's belly. Her belly will be distended, and it might be more difficult for her to move around. Make sure your expecting mother is in a calm, quiet place where she can prepare for labor.

Fast Fact

Guinea pig babies are precocial, which means they're born fully developed; they have their eyes open, all their hair, and a full set of teeth.

Do Pregnant Guinea Pigs Need to Be Separated?

If you discover that your Guinea pig is pregnant, it might be worthwhile to separate her from others. Why? Pregnant cavies can become grumpy and pick fights with any male or other female Guinea pigs in their enclosure.

It's also possible for a Guinea pig to become pregnant immediately after giving birth if you have an unneutered male with her, so it's safest to give your expecting mamma her own cage for the duration of her pregnancy and labor.

At What Age Can Guinea Pigs Get Pregnant?

Female Guinea pigs can get pregnant as early as 2 months old. That might seem way too young, but Guinea pigs develop fairly quickly, so females reach sexual maturity after just 8 weeks. Male cavies, on the other hand, take a bit longer to mature, so they can't mate until they're at least 3 months old.

Pregnancy and Birth Complications

Everyone hopes for a smooth pregnancy and labor, but complications can happen. It's important to know the signs that something isn't right so you can get your Guinea pig the appropriate help.

Pregnancy Toxemia

Pregnancy toxemia, sometimes called ketosis, is a serious concern in Guinea pigs within the last few weeks of pregnancy. Their body essentially produces too many ketones as a result of the mamma cavy not getting enough nutrients, so the body survives on fat stores. Signs of this life-threatening condition include:

  • Not eating or drinking
  • Lethargy
  • Weakness
  • Muscle tremors
  • Disorientation
  • Coma
  • Death

Prevent pregnancy toxemia by feeding your Guinea pig high-quality and nutritious food throughout their pregnancy. Monitor her appetite and weight daily throughout the final three weeks leading up to her due date, and report any changes to your veterinarian right away.

Labor Dystocia

Guinea pig labor happens very quickly; it usually only lasts about 30 minutes, depending on how many pups she has. If it takes any longer than that, your pet might be experiencing dystocia, which translates to "difficult labor." This usually happens if a baby gets stuck in the birth canal. Other symptoms of dystocia include:

  • Labor still hasn't started after their due date.
  • Labor lasts more than 40 minutes.
  • Excessively straining without any baby produced.
  • Only a portion of a baby emerges during labor, then won't progress.
  • Excessive pain during labor.
  • Excessive bleeding during labor.

Dystocia can be fatal to a Guinea pig if the babies aren't safely removed from their birthing canal by a veterinarian. Some pets even need to have a C-section in order to deliver safely. Bring your mamma pig to the vet immediately if you notice any signs of dystocia during birth.

Care for Pregnant Guinea Pigs

Expecting baby Guinea pigs is a very exciting time, though you'll need to be especially alert during these nine weeks. Make sure your mamma pig has plenty of fresh water, Alfalfa hay, calcium-rich veggies, and a quiet enclosure away from other pets. If you notice anything out of the ordinary, let your vet know immediately so you can keep your Guinea pig and her growing pups healthy. In no time, you'll both be rewarded with little ones to care for, too.

Guinea Pig Pregnancy Week-by-Week Guide for Development & Care