This invention provides a female medical coupling port with an integrated port guide to enable more accurate and precise coupling of a male port coupling (such as the cannula of a syringe) and to prevent port exposure to non-sterile objects. The male and female ports can be arranged according to standard dimensions for male and female luer taper fittings recognized by ANSI and by ISO. This guide-shielded port is usable with the standard ANSI and ISO male cannula widely used in the medical field. In an embodiment the female port is used in medical fluid systems to receive a blunt male cannula, such as those found in the luer lock fitting of needle-less syringes and IV tubing systems to establish a mechanical coupling. Female ports allow coupling of devices (e.g. syringes and IV tubing) to a variety of medical applications including stopcocks, minimum fluid displacement medical couplings, female-to-female adapters, port dead-end caps, IV extension sets, pressure-monitoring devices, etc. The port guide can be constructed as a unitary part of the port, or can be a retrofittable structure that is either snapped into place on, for example, a female port stem, or slid onto a port, such as a minimum displacement fluid coupling. Appropriate drain ports can be provided in the port guide to prevent capture of excess fluid.