Due dates getting more and more unrealistic

[Maay87]

So I am by my calculations due 9/4/24, because I had a small procedure there is only one date that can be the conception date 16/7/23, as that’s the date me and hubby had sex. They keep moving my date further forward at each appointment and now over a full week ahead. Making my conception date when I had my period, when I was in hospital under going turn general anaesthetic at the time 6/7/23. I’m worried about the implications of potentially doing a c section on baby who isn’t as far along. Even though he is coming up big. I have a crazy voice in my head that’s starting to wonder if I was assaulted under general anaesthetic (it’s probably nothing more than 3 am gremlins in my head and fear as a previous sa victim) but now they have reared their head and it won’t shut up. And i feel like it’s starting to make me detached from the pregnancy. I didn’t test positive until 24/7/23 I was testing as I felt off, I just want them to stop moving my dates! How do I shut out the fear and the crazy voice?

So your last menstrual period was 6/7/23? Pregnancies are dated from the first day of your last menstrual period, effectively counting you as being 2 weeks pregnant when conception occurs. Using 6th of July as your last menstrual period puts you due date at 11 April 2023 so that seems to be around what you thought.

No they brought my dates to 1/4/24 from 11/4/24. They calculated my period date as 27/6/2023

How can they calculate your period date, it should be you that tells them what the last known period was. They can't make up a new day your period started.

When you do your scan, they can calculate 2 due dates: a) based on last period and b) on size of baby. However your actual due date should be based on the last period.

The key is that the c-section is not before 37 weeks if possible, so lungs are fully mature.

I told them my dates and regardless they keep bring my dates forward, I told them it was making me uncomfortable and that I knew when my period was and the only possible date of conception and they don’t want to change my date back. For further background I normally ovulate early, we thought I was well past fertile window and weren’t trying.

I believe that your due date being moved at your 12 week scan is due to the size of your baby when it is measured. They are not saying you didn’t conceive on that date, nor that your period dates are wrong. They are calculating your due date based on the size of the baby.

Same as previous poster they are calculating based on the size of the baby. My 12 week scan with DD1 put me a week ahead, I also knew the date of conception because it was off the back of a broken condom and we hadn't had sex in the two weeks prior to that.

DD actually arrived on the original due date that I had calculated. So was down as late, but for me right on time :)

The date you had sex / date of conception doesn’t matter.

The baby’s due date should be counted from the first day of your last period. However this assumes everyone ovulates at day 14, so calculators are based on you being “2 weeks pregnant” when you actually ovulate.

If you ovulated before or after day 14 the calculator won’t be accurate. This is why the measurements at the 12 week scan are used to give you a date.

I kinda get that but it’s getting I feel dramatic now from my 20 week scan they moved date three days more to the 1/4/2024 date and said baby was over 99 centile in some areas, I just don’t get how they can move my date this much, just say baby is 100 centile and leave my dates alone. I even had one midwife telling me that oh maybe your body did some thing miraculous and the egg survived days longer or some crazy bs (eggs only live 24 hours end of) dr said it was a development thing but they wouldn’t move dates anymore, then they did, it’s just not adding up and starting to want to paternity test the baby

Exactly what happened with planned first born, his due date was exactly how I predicted. For it to line up with only date in months we had sex due to me being ill and in and out of hospital and under sedation for parts of it, would mean I ovulated later than I normally do, and late in my cycle not early. Meaning Edd should have been no earlier than 9/4/24

OP I’ve had friends with IVF that have had dates move a few days. Embryos can take a while to implant. On my end - my dates always move and never add up! But to the opposite of you. I clearly grow baby’s small, especially in the beginning. At 8 weeks I often measure 6, a full two weeks behind (and an impossibility as I get HG so puke, and then test positive early). Usually I catch back up by a few days at 12 week scan. But still remain at least a week behind for the duration of pregnancy. fetal measurement is not an exact science. But I am confused when you say your due date keeps moving. I the UK my understanding (from my own pregnancy’s) is that once past 12 weeks they will plot “estimated weeks/edd” at subsequent scan’s but don’t move your due date.

I am conscious that you’ve said this is worrying you enough you want to do a paternity test. Are hospital listening to your worry’s? Have you been referred to any teams for support?

It’s much more likely that if you were in hospital and under sedation etc. your cycles were thrown off, than that someone in hospital assaulted you. Or are you worried you could have been assaulted at home?

I had ivf and my date also moved forward by a few days. Another thing to consider is that full term might just not be 40 weeks for you, every person is slightly different and babies develop at different rates

If you’re basing a potential assault in hospital purely on the dates you’ve been given I don’t think that’s rational and worry you’re suffering from anxiety or something else.

It’s really common for the date to be moved if the baby is big. It’s happened both times for me even though I knew conception date.

I know it’s not rational but everyone else’s dates are going backwards not forwards

Some foetuses are bigger than others and grow slightly faster. They move the dates according to what they see and how big the baby is getting.

In the kindest possible way I think you need to talk to someone about your anxiety, because believing you were raped while in hospital is not rational x

My date moved forward by 2 weeks and it annoyed me as I felt there was then more pressure to have the baby earlier even though I thought my original date was more accurate. However, it's important to remember that YOU are in control and have choice. I definitely recommend doing a hypo birthing course and reading up about your birth rights, it helped me feel more in control when I was worrying about it all. I also recommend you speak to your midwife to maybe be referred to the mental health midwife, if you have previously been SAd it might help to speak to someone as it can have an impact on something as life changing as birth ❤️

My due date moved forward a full week at my 12 week scan - I texted my friends saying "wow, I just got a week more pregnant 😂"

To be honest I'm just not thinking about it too much as it all blows my mind, and the baby will come when it's ready to come. I think it would help to speak to someone about your anxiety x

They will originally go off the date of your last period. Then at the 12 week scan the dates might move. They base it on size but also the development of the foetus. My cycles are longer so I was scheduled for my 12 week scan at 10 weeks, even though I told them I have longer cycles. I then got referred for another scan at 12 weeks and the difference between the development in the two scans is quite significant. So it isn’t just size that affects your dates.

After the 12 week scan they shouldn’t be moving your dates. If he’s measuring big at that point, they should be referring you for a gestational diabetes test, especially if he’s 99th percentile on dates earlier than the 12 week scan.

Not true: my LMP date was 5/2 and my EDD based on scan at 13w is 31/1.

I was told explicitly "your due date won't change now even if growth trajectory does". Has your due date been changed since your NT ("12w") scan?

My EDD was nowhere near the BD with either of my boys even though I had very exact conception dates. (Very planned and controlled conception and pregnancy due to my health) I had a gut feeling they would come earlier and I was right.

Both came early, and I was clearly ready to pop with both, I'm quite small but had huge bumps. Waters broke naturally (& spectacularly) each time before I had c- sections. Told them with my 2nd they needed to plan it earlier but they insisted I was wrong and he would come on time, he was nearly 3 weeks early so ended up with an 'emergency' planned section. Both boys perfect and healthy even though they were technically early.

Baby gestation/due dates isn't an exact science and has way more variation that you are often led to believe.

That's not true at all, mine moved forward 3 days at the 12w scan and plenty of others have the same experience.

They shouldn't be moving your due date at your 20 week scan. Between 11-14 weeks is the usual time fir a 'dating scan'. The date agreed at that point is the final due date. By 20 weeks the size can vary hugely between babies. Have they definitely changed your due date on your notes?

I knew my due date based on my period, ovulation tracking and when we had sex. I then had a couple of early scans before the 12 week scan and each time they were bringing the date forward. Then the 12 week scan dated me to be due about a week earlier than the date I knew I should be due, which logically would be impossible.
It’s nothing to worry about at all and happens to lots of people. As great as scans are they’re not totally accurate - you so often hear of people who have babies estimated to be big and end up being small or vice versa.

My baby was eventually born ‘late’ according to scans, but he was born the day before the date I had estimated 🤷🏻‍♀️

They moved both my kids forward, can't remember how much by. DS ended up coming slightly earlier than their predictions because I developed preeclampsia, DD was 2 days late - also induced for preeclampsia symptoms. You are well within your right to refuse all interventions until you reach the date you know to be baby's due date. You're allowed to refuse any interventions at all if you prefer. Just because they advise something doesn't mean it's the right thing for you and your baby

Shouldn't be a due date, but a due MONTH. Babies come any time between 38 and 42 weeks normally, and this fixation on exact dates is very troubling and causes much anxiety.