A ewe carries lambs for about 147 days, close to 5 months, with a normal range of 142 to 152 days. This sheep pregnancy week by week timeline puts the whole gestation in one chart: what the lambs are doing at each stage, what to do about scanning and feeding, and when to start the lambing watch.
Enter your breeding date in the sheep gestation calculator for exact dates, or use the lambing calculator to plan the lambing window and countdown.
Not sure she is bred? This page is the full 147 day timeline. If you are still deciding whether the ewe is pregnant at all, start with signs a sheep is pregnant for the confirmation methods, then come back for the week by week plan.
The 147 Days at a Glance
Months 1 to 2
No visible signs
Day 60 to 90
Scanning window
Month 4
Rapid lamb growth
Month 5
Udder fills
Day 142+
Lambing window
Sheep Pregnancy Timeline Chart
Five phases, one table. Print it for the lambing barn and pencil in your own dates once the calculator has given you the due date.
| Stage | Days | What Happens | What To Do |
|---|---|---|---|
| Month 1Weeks 1 to 4 | Days 1 to 30 | Eggs are fertilized and embryos implant in the uterus by roughly day 15. The ewe shows nothing at all and her routine does not change. | Write down ram exposure dates and mark day 147 on the calendar. Keep her on maintenance forage with mineral. An unbred ewe returns to heat about every 17 days, so a missed cycle is your first hint of pregnancy. |
| Month 2Weeks 5 to 9 | Days 31 to 60 | Organs are built and the placentas take over feeding the lambs. Singles versus twins is already set, though nothing shows from the outside. | A blood test can confirm pregnancy from about day 30 if you want answers early. Keep feed at maintenance: grain this early adds condition, not lambs, and fat ewes lamb harder. |
| Month 3Weeks 10 to 13 | Days 60 to 90 | The belly begins to fill, though wool hides it longer than you would expect. This is the standard window for ultrasound scanning. | Scan between day 60 and 90 to confirm pregnancy and count lambs, then sort ewes into single and twin-plus groups. Sorting now is what lets you feed each group right later without overfeeding the whole flock. |
| Month 4Weeks 14 to 17 | Days 90 to 120 | Lambs pack on the bulk of their birth weight from here to the end, and the ewe's appetite climbs with them. The udder starts developing late in the month. | Plan the grain start for multiples in the final 3 to 4 weeks (about day 118 to 125). Shear or crutch ahead of lambing if that is your system, and check body condition rather than trusting the calendar alone. |
| Month 5Weeks 18 to 21 | Days 120 to 147 | The udder fills and tightens, the vulva pinks and slackens, and the ligaments beside the tail soften in the last days. Most ewes lamb between day 142 and 152. | Assemble the lambing kit by day 135. From day 140 check the udder and vulva daily, keep twin-plus ewes on steady grain to head off twin lamb disease, and get the lambing pens bedded and ready. |
Day counts run from the breeding or ram exposure date. Averages assume about 147 days; plan for lambs any time from day 142 to 152, with triplet carrying ewes often earliest.
The Final Three Weeks: What to Watch
From about day 125, walk the ewes once a day and look at udders and vulvas instead of trusting belly size, because wool fools the eye. A udder that was a soft pouch last week and is now a tight balloon says lambing is close. In the last day or two the vulva turns pink and slack, the hollow beside the tail head deepens, and the ewe drifts to the edge of the flock to find her own spot. Ewes carrying twins or triplets deserve a second daily look in this stretch, since late pregnancy is exactly when twin lamb disease strikes: a ewe that goes dull and off feed in the final three weeks is an emergency, not a picky eater.
For the hour by hour stages once labor starts, and for the full late pregnancy symptom list, read how long sheep are pregnant alongside this timeline.
Feeding Rules: Singles vs Twins
Scanning is what makes sheep feeding cheap: once you know who is carrying what, you feed two small groups instead of overfeeding the whole flock. Singles on decent hay or pasture usually need no grain at all, and pushing grain on them just builds fat ewes and big single lambs that cause lambing trouble. Twins and triplets are the opposite story: about two thirds of their growth lands in the final month, so start them on roughly half a pound of grain a day in the last 3 to 4 weeks and build slowly. Keep hay first in every group, make no sudden feed changes in the last two weeks, and offer selenium and vitamin E as your area and your vet recommend.
When to Call the Vet
- A ewe off feed or acting dull in the final three weeks: treat pregnancy toxemia as an emergency.
- Any discharge or straining well before day 142.
- Hard straining for 30 minutes with no lamb presented, or an obviously presented lamb making no progress.
- More than about an hour of restlessness and straining with nothing delivered.
- A ewe that stays lying down, cold, or disinterested after lambing, or a ewe that will not get up at all.
Planning the ram turnout date? The sheep breeding guide covers the breeding season, and the printables page has barn ready charts. To work out whether a ewe is bred before planning this far ahead, see signs a sheep is pregnant.
Sources & References
- Merck Veterinary Manual: Ovine reproduction and gestation
- Oregon State University Extension: Sheep production resources
- University of Wisconsin Extension: Ewe nutrition and late gestation feeding
- AHDB: Scanning and lambing management guidance