My wife gave birth to a baby six months back and since then she is having irregular menstruation periods. Some times it comes after twenty days and some times in fifteen days and now almost 35 days have gone since her last periods. Although we haven't any sexual intercourse still We have done the test which has shown negative result? Please provide appropriate answer for the problem. Do we need to consult a gyne? My wife is breastfeeding the baby could this be the cause please clarify?