Magnetic manipulation of gametes and embryos using functionalized nanoparticles (NPs) offers a novel strategy to improve micromanipulation in assisted reproductive technologies (ARTs). Conjugation of functionalized magnetic NPs to a truncated version of porcine oviductal glycoprotein 1 (pOVGP1t) generates the NPOv complex, which specifically binds to the zona pellucida (ZP) of mature oocytes without internalization, enabling magnetic control. This study evaluated the effect of medium viscosity on the displacement behaviour of oocyte–NPOv complexes under a low-intensity magnetic field generated by a neodymium magnet. Oocyte–NPOv complexes were exposed to the S-02-02-N magnet (2⌀ × 2 mm, 150 g holding force) in media of different viscosities: phosphate-buffered saline (PBS), PBS supplemented with methylcellulose (MC: 0.1%, 0.5%, 1%), uterine fluid (UF) and oviductal fluid (OF). Displacement was recorded using a stereomicroscope-mounted digital camera and distance travelled, mean velocity and maximum acceleration were analyzed using Tracker (v6.0.8). Viscosity ranged from 0.92 cP in PBS to 140.83 cP in MC 1% (n = 3 replicates). Distance travelled was longer in PBS (0.39 ± 0.07 cm), MC 0.1% (0.37 ± 0.04 cm) and UF (0.35 ± 0.03 cm), and shorter in MC 1% (0.09 ± 0.02 cm; p < 0.05). Mean velocity and maximum acceleration values followed a similar trend, appearing higher in PBS and lower in MC 1% (p < 0.05). n = 7-9 per group. Data are presented as the mean ± standard deviation (SD). Overall, motion parameters declined progressively with increasing viscosity, confirming an inverse relationship between medium viscosity and magnetic responsiveness. These findings provide key insights into the design of magnetic-based micromanipulation tools for ART applications and microfluidic systems. Funding was provided by the Seneca Foundation-Murcia Region Science and Technology Agency ‘Grants for the implementation of projects for the development of scientific and technical research by competitive groups (22001/PI/22)’.