Baby after IVF, do we use protection now?

My beautiful baby girl was born January 30th 2019 after trying for 3 and half years. We tried for a little over a year before seeking help from a reproductive endocrinologist. We discovered we have male factor infertility due to lower count and poor morphology. We started timed intercourse with injectables and monitoring. I ended up conceiving but miscarried. After 6 long painful rounds we chose to go to IVF with ICSI. Our first round was successful and I was pregnant after our first transfer. Now however my cycle returned 5 weeks postpartum and has returned to normal even though I am exclusively breastfeeding. I know it is not recommended to get pregnant in the first 6 months to a year and I want to just have time to enjoy my little girl. But at the same time don’t want to worry about birth control since we are basically unable to conceive anyways. Any other IVF moms out there, did you decide to use birth control postpartum or just not worry about it? My midwife was really pushing hard to me to go on something since you “never know”.