An ectopic pregnancy is one in which the fertilized ovum is implanted in any tissue other than the uterine wall. Most ectopic pregnancies occur in the Fallopian tube (so-called tubal pregnancies), but implantation can also occur in the cervix, ovaries, and abdomen. http://en.wikipedia.org/wiki/Ectopic_pregnancy
While it is not rare, a molar pregnancy is a somewhat uncommon occurrence. Although it can technically happen to any women, pregnant women over the age of 40, as well as those women who have previously experienced a molar pregnancy, are more at risk.
http://sharedjourney.com/articles/molarpregnancy.html