I am sorry for your loss. I'm not familiar with how egg quality works...could it be the eggs just for that particular cycle i.e. could your egg quality improve the next time around?
Don't give up! You are not too old for one thing!! Second, I am proof that even after 4 miscarriages, it can still happen for you (I am 35 years old and will be 36 in January). For me, it seemed to be implantation issues, so I tried daily low dose aspirin and that seemed to do the trick.
The fact that you are conceiving is very encouraging...my husband and I figured if you keep rolling the dice, it has to work sometime! I know it's hard to stay positive, but try and keep your chin up!
<<HUGS>>

__________________
Me: 36
DH: 36
1 dd Claire
4 m/c
Oct 2005 m/c 5.5
Oct 22, 2006 dd born
ttc baby#2 since June 2007
July 2007 m/c 6w
Mar 2008 m/c 5w3d
Aug 2008 m/c 6w2d
ttc again Sept 2008
cycle 1
10 DPO - extremely faint
11 DPO - faint BFP
12 DPO (Sept 25/08) 1st beta 315 !!!!!!
14 DPO (Sept 27/08) 2nd beta 603 THANK YOU GOD!
ULTRASOUND #1 Oct 16th - 1 bean, 6w6d, HB 140
ULTRASOUND #2 Nov 3rd - 9w2d HB 185 2.5cm
TRIPLE SCREEN = Normal
"BABY" is on the WAY, kickin' up a storm!!!
Beautiful Curtis Benjamin arrives safely a week early - May 28/09 20.5 inches, 8.0 lbs.