I had the same question. I know this is late, but I thought others might be searching the internet like me! I called my friend who is a doctor to ask her as I could find no conclusive info on the internet.
A low grade fever is common after fertilization and during early (very early) pregnancy. The fertilized egg (prior to implantation) and the embryo (post implantation) are treated by the body as a foreign body, hence the fever bump. It should be a low grade fever though, not 103 or anything crazy.
But, this is kind of like most of the pre-missed period symptoms. It could indicate something else...like a cold. And, since many women experience things like sneezing, congestion, or a runny nose...Don't get your hopes up to high with that fever.
P.S. If you aren't sure if you have ovulated, you can also experience a temp boost at ovulation.