Unable to ovulate. Unicornuate uterus.

I'm 29yrs old female, 76.5Kg (Height 5.4Ft). Married for 2yrs 8months. Irregular periods from 14yrs. Diagnosed PCOS. 3D US/HSG [2014/2015] revealed Unicornuate uterus with left non-communicating rudimentary horn, Right horn communicating with patent tube. IUI done 4times. Clomiphene citrate- Resistant Letrozole given for ovulation; 2 times HMG-150IU injection & hCG trigger- 2 Follicles grown till 2.0x1.9 & IUI done- No positive result 2 times Letrozole+FSH 150IU inj.+HCG trigger- 2 follicles till 2.0- No positive result. Recently Clomiphene dosage increased to 15mg/day (5days)+FSH-b inj 50IU- No follicle growth at all. I'm taking Folic acid +Metformin (500mg) diagnosed as Vitamin D3 deficient, Thyroid profile normal, with anti-TG, anti-TSH elevated. Hence no treatment for those thyroid Abs. Kindly guide me as IUI is failed, whether IVF is the best immediate option for me & can I retain pregnancy without any complications as I have unicornuate uterus. Thanks