OBJECTIVE: To observe the changes of serum soluble interleukin-6 receptor (sIL-6R) and soluble gp130 (sgp130) in patients with pregnancy induced hypertension. METHODS: Enzyme linked immunosorbent assay (ELISA) was used to determine serum sIL-6R and sgp130 levels in 40 patients with pregnancy induced hypertension (study group), 20 normal non-pregnant women (control group I) and 20 normal pregnant women (control group II). RESULTS: In study group, sIL-6R was (196.7 +/- 12.9) micrograms/L and sgp130 was (379.4 +/- 79.3) micrograms/L. In control group I, sIL-6R was (174.8 +/- 46.2) micrograms/L and sgp130 was (273.6 +/- 28.3) micrograms/L. In control group II, sIL-6R was (174.4 +/- 48.3) micrograms/L and sgp130 was (254.4 +/- 34.7) micrograms/L. SIL-6R and sgp 130 were higher in study group than those in control groups with significant difference (P < 0.01). In study group, the more severe the patients, the higher the sIL-6R and sgp130 levels. There was significant difference (P < 0.01). There was no difference in sIL-6R and sgp130 levels between control groups (P > 0.05). CONCLUSIONS: Serum sIL-6R and sgp130 levels are related to the development of pregnancy induced hypertension.