The uterus is back to near its pre-pregnancy size in 14 to 21 days, and the discharge you see during those 3 weeks tells you whether that is happening normally. Lochia runs through 3 phases, the queen needs 2 scheduled rechecks at day 7 to 10 and day 21 to 28, and 4 findings in the first 24 hours mean a vet tonight rather than next week: fever at 39.5 C or above, foul-smelling discharge, a placenta not passed, or a queen who will not nurse.
What shrinks, and how fast
At term the pregnant uterus plus its contents weighs 0.8 to 1.2 kg in a 4 kg queen. Within 24 hours the horns drop from 1.5 to 2.0 cm in diameter to about 1.0 to 1.5 cm, and by day 7 they are 0.8 to 1.0 cm. By day 14 the horns should be 0.5 to 0.8 cm and mostly inside the pelvis; by day 21 they are barely palpable. Full histological repair takes 4 to 6 weeks, which is why the next mating waits at least 4 months. Nursing speeds the process, because each suckling pulse releases oxytocin and oxytocin drives contraction.
The other half of involution is weight. A queen loses 40 to 60 percent of her gestational gain in the first 10 days, mostly fluid, placenta and uterine tissue. Weigh her on day 1, day 10 and day 21: a queen still 1 kg above her mating weight at day 21 is either carrying retained tissue or being overfed.
The 3 lochia phases
Normal lochia is small in volume, because the queen grooms constantly and swallows most of it. What matters is colour, amount and smell, in that order. A healthy discharge has almost no odour; a discharge that smells rotten is metritis until a vet says otherwise.
| Phase | Days after birth | Colour and volume | Call the vet if |
|---|---|---|---|
| 1 | Day 0 to 3 | Red-brown, 5 to 15 mL a day | Bright red and more than 30 mL, or clots larger than 2 cm |
| 2 | Day 4 to 9 | Pink-brown to serous, 2 to 5 mL a day | Volume increases instead of falling |
| 3 | Day 10 to 21 | Clear to mucoid, under 2 mL a day, stopping by day 21 | Still coloured at day 21, or restarts after day 28 |
| Any phase | Day 0 to 21 | No pus, no gas bubbles, mild smell | Yellow-green pus, bubbles, or foul smell |
Recheck 1: day 7 to 10
This visit catches the problems that start fast. The vet takes a rectal temperature, palpates the abdomen for a soft uterus and for retained kittens, and checks all 8 mammary glands. An ultrasound at this point measures horn diameter: under 1.0 cm at day 7 is on schedule, 1.5 cm or more suggests subinvolution or retained tissue. Ask for 3 numbers on the record: temperature, horn diameter, and weight. Bring the queen's day-1 weight, because the difference is more informative than either value alone.
Recheck 2: day 21 to 28
The second visit is about closure rather than crisis. Expect horns under 0.5 cm, no palpable fluid, and discharge finished. If discharge persists past day 21, ask for vaginal cytology and a culture rather than a blind course of antibiotics; the same signs can come from retained placenta, metritis, or a vaginal tear, and each is handled differently. A queen who is bright, nursing 4 to 5 kittens and eating well at day 21 with a trace of clear mucus is usually normal and can be rechecked in 7 days instead of treated.
The 24-hour red line
Four findings do not wait for a scheduled visit. Temperature of 39.5 C or higher, taken rectally, at any point in the first 24 hours. A placenta count that does not match the kitten count: every placenta should arrive within 15 minutes to 6 hours of its kitten, so a missing one at 6 hours is a call, and the risk of metritis climbs from 24 to 48 hours. Discharge that smells foul or contains pus at any phase. And a queen who ignores the kittens, trembles, or refuses food for 24 hours, which in a fat queen also raises the risk of hepatic lipidosis within 2 to 3 days.
What slows involution
Five factors show up repeatedly. A litter of 6 or more overstretches the horns and adds 3 to 5 days. Retained placenta or a retained kitten keeps the cervix open and feeds infection. A caesarean adds surgical swelling and 2 to 4 days. Poor intake in the first week, especially protein under 30 percent on a dry-matter basis, starves the repair process. And a queen who is not nursing, because the oxytocin pulses that drive contraction are missing; a queen who rejects the litter needs help with both the kittens and her own recovery.
Planning the next litter
Wait at least 4 months, and until 1 normal oestrous cycle has passed after weaning, before the next mating. Queens bred back to back accumulate 2 risks: uterine repair that is incomplete at 8 weeks, and a body condition that never returns to 4 or 5 out of 9. Cap it at 2 litters in 18 months and 3 in 2 years, and stop earlier if either caesarean count or weight recovery fails. Track recovery against the same curve you used in pregnancy in queen weight gain tracking, and confirm boosters are timed before mating rather than during lactation in vaccination timing for breeding queens.
Postpartum log for 21 days
- Write the time of every kitten and every placenta in one line; count them at 6 hours.
- Take a rectal temperature twice a day for the first 3 days, then daily to day 10.
- Note lochia colour and volume once a day on a 1 to 3 scale, with the date.
- Weigh the queen on day 1, 10 and 21, and the kittens daily.
- Book both rechecks before the birth, and price the whole cycle with the breeding cost calculator.
Frequently asked
How long is discharge normal after a queen gives birth?
About 14 to 21 days, in 3 phases: red-brown for days 0 to 3, pink-brown for days 4 to 9, then clear mucus until day 21. Volume should fall each week. Discharge that is still coloured at day 21, smells foul, or contains pus needs a vet visit rather than another week of waiting.
How do I know if a placenta was retained?
Count placentas against kittens. Each placenta should arrive within 15 minutes to 6 hours of its kitten, so a missing one at the 6-hour mark is a call. Retained placenta keeps the cervix open and raises the risk of metritis within 24 to 48 hours, and it usually needs ultrasound rather than guesswork.
When can a queen be bred again?
At least 4 months after birth, and only after 1 normal oestrous cycle following weaning. Uterine repair takes 4 to 6 weeks at the tissue level and body condition needs to return to 4 or 5 out of 9. Keep it to 2 litters in 18 months at most.