Ugh my fiancé.

Alexis • Lost my sweet baby at 8 weeks 2 days. Ttc #2
I had a miscarriage in February. The baby passed away at 8 weeks 2 days but I didn't pass the baby until 12 weeks 4 days. Long story short. I am ready to try again for another baby but my fiancé is not ready. He said give it until summer (july) or September. Why?????? Can any one just please give me words of wisdom.