An optical waveguide fiber having a multi-segmented core surrounded by a cladding, the core having a central segment and an annular segment surrounding the central segment. The central segment has a positive relative refractive index profile, and the annular segment has a negative relative refractive index profile. The optical fiber exhibits an effective area of greater than about 75 .mu.m.sup.2 at a wavelength of about 1550 nm, a dispersion slope of less than 0.07 ps/nm.sup.2/km at a wavelength of about 1550 nm, a zero-dispersion wavelength of between about 1290 and 1330 nm, and an attenuation of less than 0.20 dB/km, and preferably less than 0.19 dB/km, at a wavelength of about 1550 nm.