How long does your vagina smell odiferous after having a baby?

It shouldn't. While you will get bleeding after delivery for a week or do followed by up to four weeks of a thin clear yellow discharge (lochia) it should not smell bad. Get to your OB and get checked out. It might only be a minor bacterial infection but may be something more serious.
Post partum. After delivery the placental membranes and tissues keep coming out of the uterus and vagina mixed with blood. This has its own peculiar smell. Usually this post partal bleeding lasts for 6-8 weeks. You should expect to get rid of the smell by then.