E.B.
Read the book "What your doctor may not tell you about premenopause" by Dr. John Lee - PRE menopause actually goes from our late 20s up until PERImenopause, which is th time right before menopause. Premenopause is basically hormonal maturity and it involves shifts in hormones depending on stress levels, nutrition, lifestyle (smoking, lack of sleep, exercise, etc). It has answers to many symptoms of hormonal imbalance, including not ovulating or not having periods. I think you'll find your answer there as far as what the next step should be to restore your fertility and be able to carry another child.
Best of luck!