Help help help help

Hello. I have a few questions regarding pregnancy. How accurate are dating ultrasounds?

Are they still reliable at 15 weeks?

I cannot remember lmp or ovulation so can I rely on my ultrasound date and edd?

How many weeks is sperm really able to cause fertilisation?

[cami_pod]

Hello,

When I went for my dating scan I was in the same boat as you as I didnt have a clue when I last had a preiod as I am very irregular. The do a lot of messurements and plot them on a graph and can tell you to the day how far gone you are. I was 12 weeks and 6 days. I asked the same questions and she said that a baby developtment and size in the first few weeks are the same for everyone - it is only the later stages I think when there are differences with size and weigh etc

[Hidden in reply to cami_pod]

Thankyou. So I am definitely 27 weeks according to scan? It's just I want to be reassured on everything! Do the ultrasounds take in to account the lmp or do you have to add that on yourself? They said first day of lmp was 5.6.12 and I'm 27 weeks from there?

[cami_pod]

As far as I am aware they dont take that into account as I didnt have a clue about mine so they cant do. I dont know about 27 weeks as I am not sure on the development of the baby at that stage as normally dating scans are offered at 12 weeks. Hopefully someone else will know x

[madjosh900]

The further along your pregnancy is, the less accurate they become. This is because the variability in the size of the baby changes. 15 week ultrasounds by qualified US technologists tend to be very accurate.