It is not unusual for a woman's cycles to change after pregnancy and birth. It is possible that in time your cycles may naturally lengthen.
However there are options available to lengthen one's cycle. One possibility is to speak to your doctor about hormonally manipulating your cycle to extend the time between periods.
Another option is to consult with a qualified practitioner of complementary medicine to discuss herbal treatments or acupuncture for lengthening your cycle. Changes in diet and exercise may also affect your cycle.
Please feel free to get back to us with any further questions.
B'Hatzlacha!