Success after multiple miscarriages

I have had 4 consecutive miscarriages over the last 3 years. The first two were early at 5-7 weeks, the third was at 18 weeks and the fourth was at 9 weeks. I’ve had my blood tested, my hubby’s blood tested, chromosomal testing, lupus and everything comes back negative. My doctor says there’s no reason why this happening according to the blood tests. Has anyone else had consecutive losses with no real reason? And or have had successful pregnancies after multiple losses?