Can a woman get one last period after conception?

Not quite, but...: The way a REAL menstrual period happens after conception is after a baby embryo is miscarried, or after an embryo grows and grows and eventually is delivered. It means a real menstrual period can happen some weeks after "a conception" to many months or years after "a conception". Example: she who gets a second pregnancy before her first period after delivery, will not have a period for >18 months.