Guinea Pig Pregnancy Calculator
Welcome to the guinea pig pregnancy calculator designed to help guinea pig owners and breeders determine their guinea pig's due date and track pregnancy milestones. Calculate your guinea pig's expected delivery date, understand gestation stages, and learn essential care tips for your expecting cavy.
Calculate Your Guinea Pig's Due Date
Enter Mating or Conception Date
Select the date when your guinea pig mated or the estimated conception date to calculate the expected delivery date.
Expected Due Date
Guinea Pig Gestation Period
Average Gestation Duration
\[ \text{Gestation Period} = 59\text{-}72 \text{ days (average: 63-68 days)} \]
Most guinea pigs give birth between 59-72 days after conception, with 63-68 days being the typical range.
The typical gestation period for guinea pigs ranges from 59 to 72 days, with most sows (female guinea pigs) delivering between days 63-68. This is notably longer than many other small rodents—mice gestate for 19-21 days, hamsters for 16-18 days. The extended gestation results in guinea pig pups being born remarkably well-developed (precocial), with fur, open eyes, and the ability to walk and eat solid food within hours of birth. Understanding your guinea pig's pregnancy timeline helps you prepare for delivery and ensure proper prenatal care.
Stages of Guinea Pig Pregnancy
Week 1-3: Early Pregnancy (Days 1-21)
What's Happening: Fertilization occurs within hours of mating. Embryos implant in the uterus around day 6-7. Early organ development begins. External signs are minimal during this period.
Signs:
- No visible physical changes
- Normal appetite and behavior continue
- Some sows may become slightly more territorial
- Weight remains relatively stable
Care Tips: Maintain normal diet with fresh vegetables, hay, and pellets. Ensure constant access to fresh water and vitamin C supplementation. Avoid stress and sudden environmental changes.
Week 4-6: Mid Pregnancy (Days 22-42)
What's Happening: Fetuses grow rapidly and major organs develop. Skeletal structure forms. The sow's body begins showing noticeable changes as pups grow larger.
Signs:
- Gradual weight gain becomes noticeable (total weight may increase by 50-100g or more)
- Abdomen begins rounding and enlarging
- Increased appetite (eating 1.5-2 times normal amount)
- May become less active or move more cautiously
- Drinking more water than usual
- Pear-shaped body profile develops by week 5-6
Care Tips: Increase food portions gradually to meet growing energy needs. Provide extra vitamin C (30-50mg daily). Ensure calcium intake is adequate but not excessive. Keep housing clean to prevent infections.
Week 7-9: Late Pregnancy (Days 43-63)
What's Happening: Pups develop fur, teeth, and claws. Movement becomes visible. The sow's pelvis begins widening in preparation for birth (symphysis pubis separation). Pups are fully formed by day 50-55.
Signs:
- Obvious abdominal enlargement—belly appears very large and pear-shaped
- Visible movement of pups inside (rippling abdomen)
- You may feel distinct pup shapes when gently palpating
- Waddling gait and reduced mobility
- Increased resting periods and less activity
- Possible nesting behavior (rearranging bedding)
- Pelvis widens noticeably (can feel 2-finger gap around day 60+)
- Possible discharge from birth canal near due date
Care Tips: Provide softer, more comfortable bedding. Ensure food and water are easily accessible (closer to hiding spots). Reduce handling to minimal, gentle contact only. Prepare birthing supplies. Monitor for signs of labor distress.
Week 10+: Overdue (Days 70+)
Important: If your guinea pig hasn't delivered by day 72, veterinary attention is necessary. Overdue pregnancies can lead to serious complications including dystocia (difficult birth), stillbirth, or maternal health issues.
Action Required:
- Contact your exotic pet veterinarian immediately if no birth by day 72
- Monitor closely for signs of distress, lethargy, or labor difficulties
- Be prepared for possible veterinary intervention including cesarean section
Guinea Pig Pregnancy Timeline
| Week | Days | Development Milestones | Observable Changes |
|---|---|---|---|
| Week 1 | 1-7 | Fertilization, cell division, early embryo | No visible changes |
| Week 2 | 8-14 | Implantation, placenta formation begins | No visible changes |
| Week 3 | 15-21 | Organ systems begin developing | Slight appetite increase possible |
| Week 4 | 22-28 | Major organs form, skeleton develops | Beginning weight gain, mild appetite increase |
| Week 5 | 29-35 | Rapid growth, features becoming distinct | Noticeable weight gain, abdomen rounding |
| Week 6 | 36-42 | Fur develops, teeth and claws form | Obvious pregnancy, pear-shaped body |
| Week 7 | 43-49 | Pups fully formed, movement increases | Large belly, visible movement, waddling |
| Week 8 | 50-56 | Final growth phase, pelvis widening | Maximum size, reduced mobility |
| Week 9 | 57-63 | Ready for birth | Nesting behavior, wide pelvis, labor signs |
| Week 10 | 64-70 | Overdue window—monitor closely | Possible restlessness or lethargy |
Essential Pregnancy Care
Nutrition During Pregnancy
Proper nutrition is absolutely critical for guinea pig pregnancy due to the long gestation period and well-developed pups at birth.
- Vitamin C: Increase daily vitamin C to 30-50mg (pregnant guinea pigs cannot synthesize vitamin C and need supplementation). Provide vitamin C-rich vegetables like bell peppers, kale, parsley
- Unlimited Timothy Hay: Essential for digestive health and calcium. Must be available 24/7
- Pellets: High-quality guinea pig pellets (not rabbit pellets) with added vitamin C. Increase portions by 50-100% as pregnancy progresses
- Fresh Vegetables: Daily variety including leafy greens (romaine, kale, cilantro), bell peppers, cucumber, small amounts of carrot
- Water: Unlimited access to fresh water. Pregnant sows drink significantly more. Change water daily
- Calcium: Important for fetal bone development and preventing pregnancy toxemia. Found in leafy greens and hay. Don't over-supplement
- Small Frequent Meals: In late pregnancy, offer food 3-4 times daily as stomach space decreases
Housing and Environment
Safe, stress-free housing reduces pregnancy complications and supports maternal health.
- Separate Housing: Remove male guinea pigs immediately after confirmed pregnancy. Males can rebreed females within hours of birth
- Spacious Cage: Minimum 10.5 square feet (for one pregnant sow). She needs room to move despite reduced mobility
- Low Entry Points: Ensure hideouts and food/water are easily accessible without climbing or jumping
- Soft Bedding: Use fleece liners or paper-based bedding (avoid cedar/pine shavings). Change frequently for hygiene
- Quiet Location: Minimize loud noises, sudden movements, and stress. Pregnant guinea pigs are sensitive to stress
- Temperature: Maintain 18-24°C (65-75°F). Avoid temperature extremes and drafts
- Companionship: If housed with other females, ensure they get along well. Aggression causes stress and complications
Veterinary Care
Guinea pigs have unique pregnancy risks requiring specialized exotic pet veterinary care.
- Pre-Breeding Check: Ideally, have sow examined before breeding to assess health and weight. Sows under 6 months or over 8 months old have higher risk
- Pregnancy Confirmation (Day 21-30): Veterinary examination confirms pregnancy via palpation or ultrasound. Discuss care plan
- Mid-Pregnancy Check (Day 40-50): Assessment of maternal health, weight gain, and fetal development. Discuss emergency preparedness
- Pre-Birth Monitoring (Day 55+): Monitor pelvis widening daily. Contact vet if unusual symptoms arise
- Emergency Preparedness: Know your exotic vet's emergency contact. Guinea pig pregnancy complications can be life-threatening
Monitoring and Warning Signs
Daily monitoring helps detect problems early when intervention is most effective.
- Daily Weighing: Weigh your guinea pig daily during pregnancy. Steady weight gain is normal; sudden weight loss indicates problems
- Appetite Monitoring: Decreased appetite or not eating for 12+ hours is an emergency in guinea pigs
- Activity Level: Some decreased activity is normal in late pregnancy, but lethargy or inability to move requires immediate veterinary attention
- Pelvis Check (Days 55+): Gently feel pelvis area daily. Proper widening (2-finger gap) indicates body preparing for birth
- Watch for Pregnancy Toxemia: Signs include lethargy, no appetite, difficulty moving, breathing problems, seizures—life-threatening emergency
Signs of Impending Birth
Normal Labor Signs (Birth Approaching):
- Symphysis pubis (pelvis opening) widens to approximately 2 fingers wide (15-20mm) 24-48 hours before birth
- Increased restlessness—pacing, unable to settle comfortably
- Slight decrease in appetite (though complete loss of appetite indicates emergency)
- Nesting behavior—rearranging bedding, seeking quiet corners
- Possible slight bloody or mucous discharge from birth canal
- Increased vocalizations (soft chittering or purring)
- Frequent position changes—sitting up, lying down repeatedly
During Active Labor:
- Contractions visible as abdominal tightening
- Sow adopts birthing position (squatting or standing)
- Pups delivered typically within 5-10 minutes each
- Mother cleans pups immediately after birth
- Total birthing process usually completes within 30 minutes (but can take longer with larger litters)
Emergency Signs (Contact Exotic Vet Immediately):
- Straining continuously for more than 15-20 minutes without producing a pup
- More than 10-15 minutes between pups during active labor
- Heavy bleeding or foul-smelling discharge
- Pup visible but not delivered after 10 minutes
- Complete loss of appetite or not eating for 12+ hours
- Extreme lethargy, difficulty breathing, or collapse
- Seizures, convulsions, or inability to walk (pregnancy toxemia symptoms)
- No birth by day 72 of pregnancy
- Body temperature below 36.7°C (98°F) or above 39.4°C (103°F)
- Mother ignoring or showing aggression toward newborn pups
Post-Birth Care
Newborn Pup Care
Guinea pig pups (called "pups" or "piglets") are born remarkably developed compared to other rodents.
- Precocial Development: Pups are born fully furred, eyes open, teeth present, and mobile. They can eat solid food within hours though they'll nurse for 3-4 weeks
- Nursing: Pups should nurse within 1-2 hours of birth. Mother has only 2 nipples, so pups nurse in shifts if litter is larger
- Weight: Birth weight typically 60-100g. Healthy pups gain 2-4g daily. Weigh daily to monitor growth
- Food Access: Provide same food as mother (pellets, hay, vegetables). Pups begin eating solid food within 24 hours
- Gender Separation: Male pups can breed at 3 weeks old! Separate males from mother and female pups by 21 days
- Minimum Weaning Age: Never separate pups before 21 days. Ideal weaning age is 21-28 days
Mother Guinea Pig Post-Partum Care
Post-partum care is crucial to prevent complications and support lactation.
- Nutrition: Continue high vitamin C intake (30-50mg daily). Lactating mothers need 2-3 times normal food amount. Feed unlimited pellets, hay, and vegetables
- Hydration: Ensure unlimited fresh water. Lactation causes extreme thirst
- Calcium: Important for milk production. Provide calcium-rich leafy greens (kale, dandelion greens)
- Rest: Minimize handling and disturbances. Mother needs energy for nursing and recovery
- Monitoring: Watch for signs of pregnancy toxemia (can occur post-partum), mastitis, or exhaustion
- Rebreeding Prevention: Female guinea pigs can conceive immediately after birth (postpartum estrus). Keep males separated
- Veterinary Check: Schedule post-birth examination within 24-48 hours if any concerns arise
Pregnancy Toxemia (Ketosis)
Pregnancy toxemia is the most serious complication of guinea pig pregnancy and is often fatal without immediate treatment. It occurs when the body cannot meet the high energy demands of late pregnancy, causing fat metabolism that produces toxic ketones.
Risk Factors
- First pregnancy, especially in sows over 8 months old
- Obesity or rapid weight loss during pregnancy
- Large litter size (4+ pups) increasing nutritional demands
- Stress (overcrowding, rough handling, environmental changes)
- Inadequate nutrition or sudden diet changes
- Late-stage pregnancy (days 50-70) when energy needs peak
Symptoms
- Complete loss of appetite (anorexia)
- Extreme lethargy and weakness
- Difficulty walking or complete inability to move
- Labored breathing or panting
- Muscle twitching, tremors, or seizures
- Drooling or grinding teeth (pain indicators)
- Collapse or unresponsiveness
Prevention
- Breed young sows (under 7 months old) for first pregnancy
- Maintain healthy weight before breeding (not overweight or underweight)
- Provide consistent, high-quality diet throughout pregnancy
- Ensure adequate vitamin C and calcium intake
- Minimize stress and environmental changes
- Monitor weight gain and appetite daily in late pregnancy
Treatment
Pregnancy toxemia is a life-threatening emergency requiring immediate veterinary intervention. Treatment includes intravenous fluids, glucose supplementation, calcium if needed, pain management, and possibly early delivery via cesarean section. Even with aggressive treatment, mortality rates are high (80-90%). Prevention through proper care is essential.
Frequently Asked Questions
How long are guinea pigs pregnant?
Guinea pigs have a gestation period of 59-72 days, with most pregnancies lasting 63-68 days. This is significantly longer than other small rodents—hamsters gestate for 16-18 days, mice for 19-21 days. The extended pregnancy allows guinea pig pups to develop more fully, resulting in precocial young born with fur, open eyes, and the ability to walk and eat within hours.
At what age can guinea pigs get pregnant?
Female guinea pigs (sows) can become pregnant as early as 4 weeks old, though this is extremely dangerous and should never be allowed. The ideal breeding age for first pregnancy is 4-7 months old. After 8 months of age, the pelvic bones fuse, making first-time birth extremely difficult or impossible, often requiring cesarean section. Never breed a sow for the first time after 8 months old.
How can I tell if my guinea pig is pregnant?
Early signs (weeks 3-4) are minimal. By week 5-6, you'll notice weight gain, increased appetite, and abdomen rounding into a distinct pear shape. By week 7-8, pregnancy is obvious—very large belly, visible pup movement, and waddling gait. Around day 55+, you can feel the pelvis widening. Veterinary confirmation via ultrasound or palpation is available from day 21 onward.
How many babies do guinea pigs have?
Guinea pigs typically have litters of 1-6 pups, with 2-4 being most common. First-time mothers usually have smaller litters (1-3 pups). Larger litters (5-6+) increase risks of pregnancy toxemia and difficult birth. Pup birth weight is relatively large (60-100g) compared to the mother's size, which is why larger litters are more dangerous.
Do guinea pigs need help giving birth?
Most guinea pig births proceed naturally without intervention. The mother instinctively cleans pups and chews through umbilical cords. However, monitor discreetly from a distance. If you observe prolonged straining (15-20+ minutes) without producing a pup, pups stuck in the birth canal, or signs of distress, contact your exotic veterinarian immediately. Have emergency vet contact information prepared before the due date.
Can guinea pigs get pregnant right after giving birth?
Yes! Female guinea pigs experience postpartum estrus (heat) within 2-15 hours after giving birth and can conceive immediately. This is extremely dangerous, as back-to-back pregnancies severely stress the mother's body and dramatically increase pregnancy toxemia risk. Always separate males from females before birth and ensure they cannot access the mother for at least 4-6 weeks post-birth.
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RevisionTown is committed to providing accurate, user-friendly calculators and educational resources across diverse topics. While we specialize in mathematics education for curricula like IB, AP, GCSE, and IGCSE, we also create practical tools for everyday needs, including pet care resources like this guinea pig pregnancy calculator.
Our guinea pig pregnancy calculator combines mathematical precision with practical veterinary knowledge to help guinea pig owners and breeders prepare for their pet's pregnancy and birth. We provide clear timelines, stage-by-stage guidance, and evidence-based care recommendations to ensure the best outcomes for mother guinea pigs and their pups.
Veterinary Disclaimer: This calculator and information are for educational purposes only and should not replace professional veterinary care from an exotic pet specialist. Guinea pig pregnancies carry significant risks, particularly pregnancy toxemia. Every pregnancy is unique, and complications can arise unexpectedly. Always consult with a licensed exotic animal veterinarian for pregnancy confirmation, prenatal care, birth planning, and any health concerns. Gestation periods vary by individual. In case of emergency or concerning symptoms, contact your exotic pet veterinarian or emergency animal hospital immediately. Guinea pigs require specialized care different from cats and dogs.