as long as i know she is not allowed to marry in next 40 days or something and she is also wife of her husband.
hope brother will quote some hadiths.
According to the Islamic shari’a, the ‘idda is a waiting period with certain exigencies required of a woman when the appropriate condition exists—either divorce or death (of her husband). As for divorce, the ‘idda for a pregnant woman is until she delivers her child, and for one who still menstruates, it is three menstrual cycles, whereas for one who is either too young or too old to menstruate, it is three months.
As for the widow whose husband has passed away, if she is pregnant then her ‘idda is until she delivers her child; otherwise, it is
four months and ten days.