A single-mode optical fiber includes a central core, an intermediate cladding, a buried trench, and optical cladding. The central core has an outer radius r1 and a refractive index difference Δn1 relative to the optical cladding. The intermediate cladding has an outer radius r2 and a refractive index difference Δn2 relative to the optical cladding. The buried trench has an outer radius r3 and a refractive index difference Δn3 relative to the optical cladding. The optical fiber typically has an effective area of about 150 μm2 or greater at a wavelength of 1550 nanometers and exhibits low bending losses.