Due date

mchildress1126

I had my son last August and just found I'm pregnant but my cycle is so off since I had him. An average cycle is 42 days I have no clue how to really calculate it if you calculate the due date from my last cycle I should be 6w4 days I had a ultrasound to confirm pregnancy and they couldn't see baby only the sac the tech said I am only 4 weeks and couldn't measure the due date since the baby wasn't formed yet
is this normal 

meggyme

Due dates based on LMP are based on a regular 28 day cycle. If your cycle isn't the textbook length, your due date would be off. Hopefully when you go back they'll be able to better measure baby and formulate a due date.

karabearrr

Mine is about the same as yours, I had very irregular periods. They were able to more accurately give me measurements and baby's due date when I was closer to 11-12 weeks.

Minger86

If you have a long cycle, then you likely O'd later than expected. I think the norm is to O 12-14 days before the start of your next period. 

mchildress1126

Thank you ladies that makes me feel a little better I will keep y'all posted

allthingscozy

With my pregnancy I went in and found out I had ovulated a week later than I had thought. While I had not been pregnant before I had struggled with irregular cycles. And if you are only 5 weeks or so there wouldn't be much to see there yet. Hope all turns out well for your Pregnancy

clairemwalker

@minger86 probably has it on the money. The follocular phase (before you ovulate) is more random and can change from woman to woman, sometimes even cycle to cycle. The luteal phase (after you ovulate) is usually much less variable. The average length luteal phase is approx 11-16 days and is usually around the same length every month so if you have a 41 day cycle you probably didnt ovulate until day 27-28. I have i myself dont ov until approx cd21, i have a 33ish day cycle. The whole LMP based dating system doesnt really take this into account, it assumes that you ov around cd14 - essentially calculating nearly another 2 weeks of foetal growth then has actually happened. Which would explain why you arent as
far along. Disclaimer, i am doc, but this is what i have gleaned while TTGP

vrj0522

I used to have 35-42 day cycles a few years ago. Through temping I determined that my luteal phase is always 14 days. I had a 42 day cycle when I became pregnant the first time and that put my official start of pregnancy as day 14 of my cycle (42 minus 28 days). Because LPs are not very long, a long cycle is simply an indication of later ovulation. If you are similar to me and are saying 6w4d based on LMP, then you really would be more like 4w4d but if you have a shorter luteal phase, then you might be even less far along because that means that you ovulated a 1-3 days later.