High fever following postpartum administration of sublingual misoprostol

Abstract

Objective: To explore what triggers an elevated body temperature of > or =40.0 degrees C in some women given misoprostol, a prostaglandin E1 analogue, for postpartum haemorrhage (PPH).

Design: Post hoc analysis.

Setting: One tertiary-level hospital in Quito, Ecuador.

Population: A cohort of 58 women with a fever of above 40 degrees C following treatment with sublingual misoprostol (800 micrograms) for PPH.

Methods: Side effects were documented for 163 Ecuadorian women given sublingual misoprostol to treat their PPH. Women's body temperatures were measured, and if they had a fever of > or =40.0 degrees C, measurements were taken hourly until the fever subsided. Temperature trends were analysed, and the possible physiological mechanisms by which postpartum misoprostol produces a high fever were explored.

Main outcome measures: The onset, duration, peak temperatures, and treatments administered for cases with a high fever.

Results: Fifty-eight of 163 women (35.6%) treated with misoprostol experienced a fever of > or =40.0 degrees C. High fevers followed a predictable pattern, often preceded by moderate/severe shivering within 20 minutes of treatment. Body temperatures peaked 1-2 hours post-treatment, and gradually declined over 3 hours. Fevers were transient and did not lead to any hospitalisation. Baseline characteristics were comparable among women who did and did not develop a high fever, except for known previous PPH and time to placental expulsion.

Conclusions: An unexpectedly high rate of elevated body temperature of > or =40.0 degrees C was documented in Ecuador following sublingually administered misoprostol. It is unclear why temperatures > or =40.0 degrees C occurred with a greater frequency in Ecuador than in other study populations using similar treatment regimens for PPH. Pharmacogenetic studies may shed further light on variations in individuals' responses to misoprostol.

Figure 1

Mean misoprostol plasma concentrations after sublingual administration of misoprostol (800 micrograms), and mean temperatures of 58 cases of high fever over time.