Hi,
I had this last week with a scan at 6+3 measuring 3.5mm and a heartbeat of 98. She told me it had me measuring at 6 weeks. I am pretty certain of my dates as I was tracking LH and Progesterone so know roughly when I ovulated. We have a scan on Tuesday to see if it’s progressing but I’ve done so much googling since then to try and reassure myself.
Firstly I don’t think if it was below 5 weeks they’d be able to see a Fetal pole or a heartbeat so that suggests you’re more than 5 weeks. By the measurements at my scan place you’d have been 6 weeks too so that’s something to hopefully reassure you. They are also so tiny at this stage that the smallest miscalculation will throw the dating off, there’s a reason the NHS date at 12 weeks and some private scan places won’t see you until 8 weeks as before then it’s all too unreliable. I came across these sites which were somewhat reassuring too.
I hope it helps, the below has made me feel a little better so I am just trying to focus on that rather than using mumsnet where it’s seems it can go either way (as it can in a pregnancy where someone measured on track at their early scan).
x
https://www.hindawi.com/journals/isrn/2012/938583/tab4/
This is from the American pregnancy association (I’m not American):
Gestational Age Week 6 (Fetal age: 4 weeks)Between 5 ½ to 6 ½ weeks, a fetal pole or even a fetal heartbeat may be detected by vaginal ultrasound. The fetal pole is the first visible sign of a developing embryo. This pole structure actually has some curve to it with the embryo’s head at one end and what looks like a tail at the other end.
The fetal pole now allows for crown-to-rump measurements (CRL) to be taken so that pregnancy dating can be a bit more accurate. The fetal pole may be seen at a crown-rump length (CRL) of 2-4 mm, and the heartbeat may be seen as a regular flutter when the CRL has reached 5mm.
This is from the miscarriage association:
When can I have an ultrasound scan? When can you see the baby’s heartbeat?An ultrasound scan may be able to detect a pregnancy and a heartbeat in a normal pregnancy at around 6 weeks, but this varies a great deal and isn’t usually advised. All too often, a scan at 6 weeks shows very little or nothing, even in a perfectly developing pregnancy, and that might actually make you more anxious. Coping with uncertainty can be very difficult but waiting a week or 10 days will make the findings much clearer.