Lactational amenorrhea is a natural contraceptive method that is effective

Lactational amenorrhea (absence of menstruation) method is based on the fact that ovulation and therefore the cycle do not occur during the period of intense lactation following parturition. Therefore, as long as the mother breast-feeds the child fully, chances of conception are almost nil. However, this method has been
reported to be effective only upto a maximum period of six months following parturition.