Serotonin excretion was investigated in the nausea and vomiting associ
ated with hyperemesis gravidarum. Urinary hydroxyindoleacetic acid was
measured in 13 gravid women with hyperemesis gravidarum, 10 gravid wo
men without nausea and vomiting, and 10 nongravid women of similar age
not taking contraceptive pills. No significant difference in the urin
ary excretion of hydroxyindoleacetic acid was found among the groups.
Hyperemesis gravidarum is not associated with an increase of serotonin
secretion.