I saw a screenshot on here awhile ago of someone that had 6-7 Sims abducted in a San Myshuno community area at the same time. All townies if I remember correctly. I think it was in the Spice District. o.O
Never had more than one abducted at a time in my saves though. They seem to love Scientists, which makes sense I guess. I had an Alien Scientist that got abducted all the time. One time, he looked straight at me when he was going up in the beam with this quirky look on his face, almost as if he was thinking, "Again? Can you believe this? Why? I'm one of them! Sheesh!" lol
https://i.imgur.com/Rppmgop.png
EDIT: BTW @WildIrishBanshee, he never came back pregnant after taking a trip back home 4 times. I don't think it's possible for Aliens to be impregnated in an abduction so it must be your MCCC setting if they're both pregnant. Either that or Romeo just was incredibly lucky he didn't get a bun in the oven. o.O