First trimester · Days 15–21

Week 3 of dog pregnancy: implantation

Around day 16 to 18 the embryos attach to the uterine wall and the placentas begin to form.

Updated October 2026 · Information only, not veterinary advice

What you may notice

  • A slightly lower appetite for a day or two.
  • She may be clingier or sleepier than usual.

Care and feeding

Some dogs become clingy or have a slightly reduced appetite for a day or two. Keep exercise gentle and regular.

Keep her normal diet. If she skips a meal, offer it again later.

Vet this week

Plan the confirmation scan for the end of this week or the next.

Questions

Frequently asked questions

Why is my pregnant dog so clingy?

Hormone changes around implantation can make some dogs more affectionate or sleepy. It usually settles within a couple of weeks.

When should I book the ultrasound?

Book it now for the end of week 4 (about day 25 to 30). Clinics fill up.

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