We present a swept-source polarization-sensitive optical coherence tomography system based on a polarization-maintaining fiber interferometer. The system produces reflectivity and birefringence information along a depth profile with a single sweep of the optical spectrum. Unlike single-mode fiber systems, retardance and relative optical axis orientation images are calculated without compensation. The source is a 45 mW polygon-based swept-source centered at 1290 nm and tuned at a rate of 28 kHz. The interferometer consists of a single polarizationmaintaining coupler that utilizes balanced detection for improved performance. Characterization data shows that this system yields accurate measurements with high sensitivity (106.2 dB) comparable to conventional setups. Images of biological tissues with high dynamic range are demonstrated.