Understanding Early Pregnancy Loss: Was it Radiation, Lifting, or Age?

Question
About 8 weeks ago, I strained my sternum at work, due to lifting which required me to have 6 chest xrays done. When they speak of excess radiation may be the cause of a miss, could it have been the xrays? I have since healed but have had to continue lifting and moving 45 lb buckets around. I am 43, had 3 successful pregnancys previous to this loss at 5 weeks gestation. I am wondering if the loss was due to my age,lifting, radiation or severe stress.I felt a lot of pressure and gas in my lower abdoman prior to spotting, then bleeding. But I only bled slightly heavy for 2 days, now today is my 5th day and I only have brown spotting. It was just like a regular period. Is this normal?

Answer
The risk of miscarriage in early pregnancy is  seen in 15-20% of every pregnancy. There is nothing you can do to cause a miscarriage and there is nothing you can do to prevent a miscarriage. It is not caused by diagnositic X-rays (even six of them) and is not caused by heavy lifting, age, or stress. Usually, later miscarriages can be due to infection or illnesses such as diabetes, obesity, alcohol, lupus, collagen vascular diseases, phospholipid disease. We do not know why early miscarriages occur.