Abstract. Human myometrium was studied for specific binding of PGE2 and PGF2α. PGF2α-binding was almost undetectable, but specific binding sites for PGE2 with high affinity (KD = 2.7 ± 0.4 × 10−9 m were demonstrated. The binding capacity for PGE2 exhibited a topically different distribution pattern with the highest values in the central parts and low to undetectable levels in the cervical region. Binding characteristics were analyzed by receptor kinetics, revealing a homogenous receptor population. Binding capacity in uteri obtained from post-menopausal women was of the order of 900–940 fmol/mg protein. Oestrogen pre-treatment and pregnancy were associated with a 3-fold reduction of the PGE2-binding capacity.