Being obese will result in thyroid disorder and other ovulation issues, not just that even after conceiving carrying the baby for 9 months is big task as well. So making small changes in diet and daily activities will help a lot. I was 94 kgs and showed many obese women who got pregnant and kept giving excuses but things just dint work out as my PCOS worsened. I decided to loose weight came to 79 kgs got conceived naturally not just that so far I'm in same weight and having healthy pregnancy. Avoiding outside food will help a lot. All the best.