No periods one year after baby

I have 3 children (6, 4, 2) and have breast-fed each for a year.  After my first child, my periods took 6 months to return after I stopped breast-feeding.  After my second child, my periods returned 3 months after I ceased breast-feeding.

However, it is now 13 months after I stopped breast-feeding my 3rd child and my periods have still not returned.  

I experience a hormonal cycle, as I feel as if I am about to have a period each month, but it never actually comes.

I am 40, have been vegetarian (60% raw food, almost vegan) for 21 years, take nutritional supplements to ensure no mineral/vitamin deficiencies, exercise moderately and am otherwise extremely energetic and healthy and love life!

Early menopause does not run in our family, and I have no menopausal symptoms, other than amenorrhea.

Please could you enlighten me if you are able to.

Thanks!

Sarah

[Machelle Seibel, MD]

A. There are many reasons for a delay in your menses returning.  Here are some of the main ones and what to do next. Your weight might be too low; your nutritional input might not be as complete as you believe it to be; or your hormone levels could be off.  Your age could be a factor in that some of the things I mentioned above could have been borderline in the past and because you are closer to menopause, the same circumstances are now affecting you periods.  

If you are over one year without your period, see your doctor.  Ask to have a blood test run for FSH (follicle stimulating hormone).  FSH goes up if you are approaching menopause.  Also get a blood test for Prolactin.  That hormone is elevated to allow for breast feeding (pro lactation) and if it stays up, can be a sign of an overactive pituitary gland.  A careful exam by your doctor could provide other clues as well. You might also consider a consultation with a nutritionist to be sure you haven