Week
Week 5
Each baby is about the size of a sesame seed this week
- Weight each
- Too tiny to weigh
- Length each
- 0.2 cm · 0.1 in
What's happening this week
Right now, three tiny hearts are just starting to take shape — no bigger than a flicker, but each one about to find its own rhythm. Three brains and spines are being sketched out too, the very first lines of three completely different people.
If a scan has already shown you three little sacs, that's the moment plenty of parents say knocked the wind clean out of them — in the best way. From here, each one will grow entirely at its own pace, on its own schedule.
Three little wonders this week
- Three hearts are being built this week, each starting as a simple little tube that will soon start to twitch.
- Folic acid is doing quietly heroic work right now, helping three tiny spines and brains form properly.
- An early peek might already show three separate little sacs — the very first family photo, blurry as it is.
The triplet twist
A one-baby scan is just looking for a single sac. Yours is also working out how your three are arranged and sharing space in there, which shapes how closely and how often you'll be looked after for the rest of the pregnancy.
Something to look forward to
- Next week, you might get to hear three little heartbeats in a single appointment.
- You're about 7 weeks from the 12-week scan, a lovely look at all three together.
To Mom:
Three tiny hearts are just beginning to find their rhythm, a beautiful flicker of what's to come. It's okay to feel overwhelmed by the news; your body is already a cozy sanctuary for your three little sesame seeds.