Marc Anthony and Jennifer Lopez by Jordan Strauss/WireImage.com Marc Anthony and Jennifer Lopez by Jordan Strauss/WireImage.com

Capping off a seemingly 18-month gestation period, Jennifer Lopez in the wee hours of Friday morning gave birth to twins - one with a stem, one without - marking her and hubby Marc Anthony's first offspring.

J.Lo's rep tells People (who reportedly is offering $6 mil for the first twin pics, this despite the fact that their Aguilera-baby cover only sold so-so) that the tots arrived shortly after midnight in Long Island. The girl clocked in at 5 pounds, 7 ounces, while her minutes-younger bro weighed an even 6. "Jennifer and Marc are delighted, thrilled and over the moon," her flack tells the glossy.