First time posting and looking for advice...

We miscarried at about 6 weeks, but didn't find out the baby stopped developing until the 11 week ultrasound. My body didn't miscarry naturally, so we opted for a D&C.; I was just ready for everything to be over physically, and didn't want to wait any longer for my body to do it naturally.

It's been 3 weeks since the D&C;, and my hcg levels are down to 21. Had the follow up appointment yesterday and everything is good. The doctor is implying that we shouldn't try again until it's below 5. Does anyone know why? Is it a risk? Should we be using condoms until I get a test showing hcg levels have decreased? Is it possible to get pregnant before the hcg levels dip down below 5?