If you are 5'7" & 146 pounds, you are not overweight by any stretch of the imagination. Your BMI is 22.9, which is well within the normal range of 18.5 to 24.9. If your GYN is telling you to lose weight still, you need to find a new one. If he is implying that you are not able to ovulate because you're overweight, he's definitely full of it.
I'll reiterate...I dislike women worrying about how much weight they gain during pregnancy. The thing is, a very large amount of what you gain during pregnancy is phantom weight that will disappear right after you give birth. The average baby weighs 7 pounds, and amniotic fluid isn't light-weight either. If you only "gain" ten pounds during your pregnancy, then chances are you'll actually have
lost weight in regards to what is actually you. If you make certain to eat a healthy diet during pregnancy, and you only gain ten pounds, then that's fine. But if you're obsessively counting every calorie and fat gram and obsessing over how much weight you gain, then that's stress that you do
not need, and is likely to result in you being undernourished and tired at a time when you most need your energy.
I know you said you don't ovulate on your own. Do you know if you have PCOS? There is a very good board on this site that handles PCOS. I also encourage you to check out
The InterNational Council on Infertility Information Dissemination. This is the best resource I know of online for infertility information. The lady who started the site overcame infertility to have two children, and is incredibly knowledgeable (I have no affiliation with the site aside from an acquaintance with the founder and having leared more about my own PCOS from that site than all other resources--including doctors--put together).
I'll get off my soapbox now. But
please, if you find your doctor continuing to be less than helpful, look for another one or try to obtain a referral to a Reproductive Endocrinologist. The sad truth is that very few doctors, even gynecologists, seem to be at all knowledgeable about reproductive disorders. I have been told variously that there is
no treatment for PCOS, that birth control pills are the only treatment, and that I have that disorder because I am overweight, all of which are complete falsehoods that could be easily dissipated with about ten minutes of research. When you're dealing with infertility, it's not just your physical health at stake but also your mental/emotional health and the health of your relationship.