Guinea Pig Pregnancy Calculator

May 2025
SuMoTuWeThFrSa
27282930123
45678910
11121314151617
18192021222324
25262728293031
1234567
A guinea pig bred on 6 May 2025 has an approximate due date of

Thursday, July 10, 2025

The due date could fall between 4 Jul and 17 Jul. Learn more about the Key Pregnancy Milestones.

64 Days Until Birth (Approx.)
Photo of calculator author Wes NolteCreated by Wes Nolte.Last updated May 2, 2025.

Guinea Pig Pregnancy Milestones (Approximate Timeline)

This table outlines key stages during a typical ~65-day guinea pig pregnancy, starting from the breeding date you selected (6 May 2025). Dates are approximate.

PhaseApprox. Time After BreedingKey Developments & Signs
Early PregnancyWeeks 1-2 (Days 1-14)
Starting: 6 May
  • Fertilization and embryo development begins.
  • Few visible external signs.
  • Some sows may show slightly increased appetite.
Mid PregnancyWeeks 3-5 (Days 15-35)
Starting: 20 May
  • Noticeable weight gain begins.
  • Abdomen starts to enlarge.
  • Nipples become more prominent around day 32.
  • Veterinarian may be able to palpate fetuses.
Late PregnancyWeeks 6-9 (Days 36-65)
Starting: 10 Jun
  • Significant abdominal enlargement.
  • Fetal movements may be visible externally.
  • Sow may become less active, eat more, and nest.
  • Pelvic bones begin to spread in preparation for birth.
Birth (Parturition)~Day 65
Est. Due Date: 10 Jul
  • Labor typically lasts 30 minutes to 1 hour.
  • Pups are born fully developed with open eyes and fur.
  • Average litter size is 2-4 pups, though can range from 1-6.
  • Pups can walk and eat solid food shortly after birth.
Post-BirthAfter Birth
Date: 10 Jul
  • Sow will clean pups and placenta.
  • Pups will nurse immediately.
  • Monitor the mother and babies for any complications.
  • Ensure the mother has plenty of fresh food and water.

How to Calculate a Guinea Pig's Due Date

Calculating when your guinea pig will give birth is important for proper preparation and care. Here's how to estimate the due date:

  1. Record the Mating Date: Note the date when your female guinea pig (sow) was exposed to the male (boar). If multiple matings occurred, use the earliest date for estimation.
  2. Understand the Gestation Period: The average guinea pig pregnancy lasts about 65 days (about 9 weeks).
  3. Consider the Range: Guinea pig pregnancies can vary from 59 to 72 days, depending on litter size, the sow's health, and other factors.
  4. Calculate the Estimated Due Date: Add 65 days to the breeding date. This calculator does this automatically.
  5. Monitor for Signs: As the estimated due date approaches, watch for signs of impending birth such as widening of the pelvic bones, restlessness, and nesting behavior.

Signs of Guinea Pig Pregnancy

It can be challenging to detect pregnancy in guinea pigs during the early stages, but several signs may become apparent as the pregnancy progresses:

  • Weight Gain: Pregnant sows will steadily gain weight, especially in the later stages of pregnancy.
  • Enlarged Abdomen: The abdomen will visibly expand, particularly in the final weeks.
  • Changes in Behavior: The sow may become less active and prefer to rest more often.
  • Increased Appetite: Pregnant guinea pigs often eat more to support the developing pups.
  • Palpable Fetuses: After about 4 weeks, a veterinarian may be able to feel the puppies through gentle palpation.

Guinea Pig Gestation Reference Table (Based on 65 Days)

This table provides estimated due dates based on a 65-day gestation period for breeding dates throughout the year.

Care Tips for Pregnant Guinea Pigs

  • Proper Nutrition: Ensure your pregnant sow receives adequate nutrition, including plenty of vitamin C, fresh vegetables, and high-quality guinea pig food.
  • Separate from Males: Remove the male to prevent immediate post-birth mating, which can strain the mother's health.
  • Clean Habitat: Maintain a clean and comfortable environment with fresh bedding.
  • Avoid Stress: Minimize handling and stress, especially in the late stages of pregnancy.
  • Veterinary Care: Consider a vet check-up to confirm the pregnancy and ensure the sow is healthy.
  • Prepare for Birth: Have a comfortable, clean birthing area ready as the due date approaches.

References

  • Richardson, V. (2000). Diseases of Domestic Guinea Pigs. Blackwell Science.
  • Meredith, A., & Redrobe, S. (2002). BSAVA Manual of Exotic Pets. British Small Animal Veterinary Association.
  • Quesenberry, K., & Carpenter, J. (2012). Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery. Elsevier Health Sciences.