Reflux symptoms are common in pregnancy, but their association with fat ingestion is unclear.

To investigate an association of dietary fats with heartburn and regurgitation in pregnancy.

This is a prospective study in which 89 pregnant women (gestational age 34 ± 4 weeks) attending a low-risk prenatal outpatient clinic were asked to provide information on the frequency they experienced heartburn and regurgitation. Fat ingestion was estimated by means of a 24-h diet record. Symptomatic patients were compared with those with no reflux symptoms (n = 20).

Heartburn once a week or more often occurred in 56 of the 89 patients (63%). The ingested amount of polyunsaturated fatty acids was higher in patients with heartburn (11.2 ± 6.4 vs. 7.7 ± 3.5 mg; P = 0.022) than in controls after adjusting for age, gain weight during pregnancy, ingestion of caffeine and vitamin C, and total energetic intake. The ingestion of monounsaturated fatty acids was higher in patients with heartburn, but with a borderline statistical significance (16.1 ± 11 vs. 11.8 ± 6.5 mg; P = 0.061). No association was observed between the consumption of fats and regurgitation.

This study suggests that heartburn in the third trimester of pregnancy is associated with the ingestion of polyunsaturated fatty acids.