Hi, It is good that you have maintained normal BMI. Are your periods regular?. Is there any problem with ovulation? Why is letroz prescribed to you? You see of the couples trying for pregnancy, 85% will conceive in the first year. Of the remaining 50% conceive in the second year. The main obstacle in your case is that you both are not staying together. It would be a wise decision for you to take visa and stay with your husband for at least a year. I strongly suggest this. Ovulation occurs 14 days before the date of your next period. Let me give an example. If your period cycle is of 30 days duration, then ovulation usually occurs on day 16 of your menstrual cycle. Sperms remain alive in the female body for 6 days. The life span of egg is 1 day. So the fertile window is from day 11 to day 17. Instead of getting stressed with these calculations, it is advisable to have regular intercourse at least three times in a week. Take one tablet of folic acid daily. If smoking, you both must quit smoking. I hope I have answered to your satisfaction.