Howdy folks. Well, it will be a while yet before we in the West get our hands on the official English translation for volume 38 of Negima!, but in the meantime, Hata provided a bit more info.
nazinani negima 38
question: wasn't Negi born in 1994? (book 02)
Ken: this book is the correct one, consider all others typo or mistakes.
question: who did that?
what happen to Arika after giving birth to Negi is BY DESIGN not made public.
( it just means she might be featured in future Negima story, whether after death in flashback or alive in some capacity is anyone's guess.)
I've long been of the opinion that Arika was more of an afterthought by Akamatsu-sensei. I say this because until Negi's and his magical, battle harem traveled to the Magic World, he never thought of his mother, nor did anyone else say a peep about his mother. It was so odd to me, and it was one of the reasons I thought Akamatsu-sensei might be going the route that had Nagi disguise himself as his own son, fake his death, block his memories (ala Asuna), etc. I can't imagine what would be so mysterious about her, and what we've learned to date doesn't say a great deal, other than she was the perfect foil for Nagi, and she cared a great deal about her people, and the peoples of the Magic World.
Although I was as disappointed as anyone over how Negima! came to a rapid halt, it seems fairly clear that Akamatsu-sensei will bring the manga back down the road. If that's the case, and if he does all the plot threads, including dealing with Eva's linkage to things, including her time with Ala Rubra, then I'll be satisfied.