6 Weeks Pregnant: The Week You Might See the Heartbeat

Last week, deep inside you, your baby's heart flickered into life and started to beat. This week, it settles into a steady rhythm, and for the first time, there is a real chance you will actually see it.

Because week six is, for so many mothers, the week of the very first scan. The week the impossible little secret you have been carrying might finally appear on a screen, right there in front of you. It is also the week your baby starts, quietly, to look like a baby. Let me show you what is happening in there.

Your baby starts to take shape

Until this week, your baby has looked like a little curl of cells, beautiful but hard to read as anything in particular. Now the first recognisable pieces arrive.

Four tiny buds push out from the sides of the body, two up top, two below. These are the very beginnings of arms and legs, and right now they look like minuscule paddles. On the head, two dark spots appear where the eyes are forming. Small dents mark the places the ears will be. The faint beginnings of a nose and a mouth are sketched in, like the first soft pencil lines of a drawing.

It is all impossibly small and impossibly fast. Piece by piece, week by week, your baby is being drawn into being.

Yes, your baby has a tiny tail right now

Here is something almost no one expects, and I love telling mothers about it.

At this exact stage, your baby has a little tail. It is the very tip of the growing spine, and for a week or two it curls out behind so that your baby looks, honestly, rather like a tiny tadpole drifting in the dark. Over the next few weeks it quietly shrinks back and tucks itself away, and becomes the tailbone you are very probably sitting on right now.

So if you see your six week scan and think it looks more like a little sea creature than a baby, you are not imagining it. That is exactly where your baby is, and it is completely, wonderfully normal. You are looking at one of the oldest and strangest and most ordinary miracles there is.

You might see the heartbeat this week

For so many mothers, this is the week of the very first scan, usually somewhere between six and nine weeks.

Picture it. A dim room, a screen turned toward you, and somewhere in the grainy grey, a tiny point of light that pulses. On, off, on, off. Around ninety to a hundred and ten times a minute, far quicker than your own heart. That flicker is your baby's heartbeat, and it is the first thing of your baby you will ever see with your own eyes. A great many mothers cry, right there in the dark, and never quite forget it.

But let me hold your hand through the other side of this, because it matters. At six weeks, it is often simply too early to see that flicker yet, and on its own, that is not a bad sign at all. Very often the embryo is just a touch too small still, and you will be asked to come back in a week or two. A scan that shows the sac and the early shapes but no heartbeat yet is, so much of the time, nothing more than a matter of days. If yours is not there straight away, breathe, and trust the next scan. Please try not to let those in-between days talk you into the worst.

How big is my baby at 6 weeks?

Around six millimetres now, still curled into that soft C-shape, still looking rather tadpole-like with its little tail.

It has roughly doubled in size since last week, and it will keep doubling at a pace it will never quite match again. Tiny, but moving astonishingly fast.

Is it normal to feel really sick now? Or to feel nothing?

Both, completely.

Week six is a classic week for symptoms to arrive in force. The queasiness that earns the name morning sickness, even though it rarely keeps to mornings. A tiredness that can floor you by mid-afternoon. Sore breasts, a need to pee constantly, sudden food aversions, and a sense of smell that seems to have been upgraded overnight.

And if you feel none of it? Still completely normal, and not a reason to worry. Some women sail through these weeks feeling almost nothing and go on to have perfectly healthy pregnancies. How you feel simply is not a reliable scorecard.

From Courtney. Week six is often where the nerves turn up, right alongside the excitement. Maybe you have a scan coming and you are quietly terrified of it. Maybe you feel dreadful and cannot tell whether that is reassuring or alarming. Maybe you feel nothing, and that frightens you just as much. I have sat beside so many women in exactly this in-between place, waiting to be told everything is okay. If that is you, please hear me. The worry does not mean something is wrong. It means you already love this baby. Be as gentle with yourself this week as you would be with a friend going through the very same thing. You are allowed to be thrilled and frightened at the same time.

The one thing to do this week

If you are taking your folate, keep it going. And if you have only just started it, you are in good company and right on time, so please carry no guilt about when you began.

And this week, add one gentle thing: be kind to your body. If the nausea and tiredness have arrived, do not try to push through them as though nothing is happening. Rest when you can, eat little and often if that helps settle your stomach, and let some things go. Your body is doing enormous, invisible work right now, and it is allowed to ask you for a slower pace.

Coming up in week seven

Next week, your baby goes through a real growth spurt, very nearly doubling in size again. Those little paddle hands begin to flatten and take shape. The brain grows at a truly astonishing speed, faster now than at any other point in the whole pregnancy. The face fills in further, and that little tail starts to disappear.

Week seven is all about extraordinary, rapid growth. I will see you there.

Written by Courtney Garland, NICU nurse, lactation consultant and mother of four, and founder of The Mama Years. This is here to inform and reassure you. It is not a substitute for medical advice, so always follow the guidance of your own doctor or midwife.

The Mama Years. 2026.

References

Cleveland Clinic. (2023). Fetal development: Stages of growth. https://my.clevelandclinic.org/health/articles/7247-fetal-development-stages-of-growth

Mayo Clinic. (2025). Fetal development: The first trimester. https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/prenatal-care/art-20045302

Merck Manual. (2024). Stages of fetal development (Consumer Version). https://www.merckmanuals.com/home/women-s-health-issues/normal-pregnancy/stages-of-fetal-development

The Mama Years is written by Courtney Garland, a NICU registered nurse and IBCLC lactation consultant, against the research. When the science is genuinely unsettled, she says so instead of guessing. Nothing here replaces the advice of the clinician looking after you.