Dear M.,
First of all, I commend you for your fortitude in continuing to try to get preganant. Although you are right about the age-related risks you mentioned, it doesn't mean you can't have a completely healthy child while in your 40s. In our day and age, there are very advanced tests which aid moms during their pregnancies and beyond.
My experiences with miscarriages are much like yours. I had my first child at age 35 and my second at age 36. I then had a couple of miscarriages and thought I wouldn't be able to get pregnant again. At age 38, I got pregnant again, but lost my baby at 42 weeks (yes, she was overdue). I was devastated and wanted to give up. I then got pregnant again a year later. Sadly enough, I only carried that baby a little over 3 months and miscarried again. By this point, I was really considered high risk, but felt that we were supposed to have one more child. Amazingly enough, I got pregnant only a few months after the last miscarriage and was thrilled!
In September of 1999, at age 41, I gave birth to a healthy baby boy. Afer birth, with the winter months approaching, he began having trouble breathing. He was hospitalized for RSV, but pulled through (We had a wonderful doctor). Now he suffers with Asthma, but is a vibrant, wonderful child.
In March of 2001, very close to my 43rd birthday, I gave birth to a beautiful baby girl. My doctor had insisted I get an amnio when pregnant with my son in 1999 (We lived in Switzerland for many years). When pregnant only 18 months later, I was told I needed to get a placental biopsy. The results were frightening. I found out that my child was at risk of birth defects and we were advised to abort. The findings showed that our daughter had Turner's Syndrome. I immediately went to work researching Turner's and found out that many Turner's babies are born without defects. We changed doctors, getting the head of OBGYN in our Swiss Kanton, and our daughter was born with very minor physical problems (rather unnoticeable actually). We will never regret our decision to follow our hearts and our doctor even told us he'd help us have another baby if we wanted to (He's quite a well known fertility doctor in the country).
With all the trials, it was completely worth the long road and my vote is that you keep trying, too! Please keep me posted as you keep trying...I will support you every step of the way! Please feel free to ask me anything at any time.
Good luck and keep the faith. Everything is possible with a positive attitude!
All the best!
D.