Sheep Gestation Calculator

Sheep pregnancy averages 147 days in this calculator, with a 144 to 152 day lambing planning window. Enter the breeding date below.

Sheep gestation at a glance

Average used by this calculator	147 days (about 4.8 months)
Window shown by this calculator	144 to 152 days after breeding
Due date formula	Breeding date + 147 days
Birth is called	Lambing
Mother	Ewe
Young	Lambs

The sheep due date is a planning estimate from breeding, and a pregnancy check can help confirm whether a ewe is carrying lambs.

Signs lambing is near

Ewes may show several physical and behavior changes as labor begins.

Udder develops
Isolation from flock
Vocalization
Nesting
Vulvar discharge
Restlessness
Pawing ground
Soft short calls
Back arches during contractions
Repeated lying down and getting up

Sheep pregnancy timeline

About day 17	A ewe returning to heat may not be pregnant.
From day 30	A blood test or transabdominal ultrasound can confirm pregnancy.
Days 40 to 70 (ideal 45 to 50)	Merck gives days 40 to 70 as the best window for counting fetuses and 45 to 50 as the ideal time for an ultrasound count of lambs.
Last 4 weeks	Energy needs rise, especially with twins or triplets.

Frequently asked questions

How long is a sheep pregnant?

The sheep calculator uses a 147 day average and a 144 to 152 day planning window after breeding; Merck also reports an average of 147 days.

How do I calculate a sheep lambing date?

Enter the breeding date and the sheep calculator adds 147 days for the estimated lambing date, then shows a 144 to 152 day Lambing Planning Window.

What signs show lambing is near?

A ewe may develop her udder, leave the flock, call, nest or show vulvar discharge as lambing begins.

When should I call a veterinarian during lambing?

NC State Extension says a ewe likely needs assistance after 30 minutes without progress during delivery. Merck says the first lamb should be born within an hour of strong contractions. Call your veterinarian for help.