Hi OP so I'm reading your post and thinking "finally someone I can relate to ! "
My story...Im 43, i have one IVF DD age 10 and 2 frozen embryos from when I was 33. I have awful health anxiety, my pregnancy was a breeze but birth not so much, it left me a little traumatised. I then had a natural chemical pregnancy 3 years later. 2 years after that we decided we were finally ready for a frozen transfer but 2 weeks after making the call lockdown came and everything went on hold. Jan 22, and a surprise natural pregnancy but I went into meltdown. Lockdown and covid had not been kind to me, I'd suffered crippling anxiety, palpitations, had numerous 24hr heart monitors, I was convinced I would die if I continued with the pregnancy. I was almost 41, I'd not taken any prenatals, I'd had alcohol and antibiotics not recommended in pregnancy. We terminated it was too much to process. 7 months later another surprise natural pregnancy, we were ready this time, but it wasn't meant to be, we found out at 13 weeks he was extremely poorly and would not survive. We terminated again.
The last 2 years have been so painful. I grieve but mostly for the first baby as I feel it was a knee jerk reaction, I just needed the right support and all would've been well. We wouldn't of then gone through the 2nd loss. There is of course, no knowing how things would've turned out but in hindsight I was younger and had less risks at 41 than I now have at almost 44.
That being said I have recently been back to the fertility clinic to discuss transfer, because like you I feel a void. The consultant laid out the risks. Chance of miscarriage is the same as in my 30s as it's related to the age of the embryo. My biggest risks are pre-eclampsia, gestational diabetes and c section. He said all manageable. There are not many women like me but it's not unheard of. Due to a complicated TFMR I had multiple procedures and he wants to check for scarring before transfer. I'm waiting on a date for that so for now I'm taking it one day at a time until I've had that procedure.
I think asking on here if you should go ahead only attracts replies and opinions from posters who either haven't experienced the pain of loss, fear and being in an impossible situation or they have had those experiences but got pregnant again and completed their family. They are the lucky ones. I've posted a few times since I was 42, and got a lot of in your 60s you'll be running round after a teenager etc. For me I'm a parent now and always will be, it doesn't matter the age of my children in my 60s. At 65 he or she would be 21. I can then retire, 65 is a fairly average age to retire isn't it?!
If you want a fourth I'd say follow your heart. And by that I also mean if you think there may be a heart issue then pay a visit to your GP first. I contacted mine for a general health check before I contacted the fertility clinic. My GP ran some blood tests. A couple of things came back that I'm working on.
There's also quite a few pregnancy over 40 Facebook groups. Loads of women on there successfully having babies into their late 40s because that's what they want for them and their families. You may find the support you need on there.
If I was in your shoes my first step would be a visit to GP, get advice on your health and any risks related to you. Best of luck !