Question about effects after TRT injections.

Robynn • Married| mom of 3 girls| Nerd@Heart | Expecting 👶🏻 #4
Hi everyone I'm new to Glow and have a long story with a question. My hubby and I have not been using protection since April of last year. At that time we decided to go with the flow and if I were to get pregnant great and if not that's fine too. Months went by and nothing, I was confused why I wasn't pregnant since with our 3 previous daughters I got pregnant within 1 month. Around September I decided to do some research online and found out Trt is like birth control for men; my husband was put on testosterone injections by his doc in Jan 2016 due to many health issues including very low libido ( which honestly was random). He got all the blood work done and not only did he have low T he also had so many other things going on, the doc said that his testosterone levels were the lowest he has ever seen. Fast forward  to November we decided together to see how he would do without the injections and fast forward to now, his libido is intact and seems he's back to normal which is great but why am I not pregnant? How long does his sperm count take to get back to normal? Thanks in advance!