Can St John´s wort (hypericum perforatum) be used during pregnancy?/nA woman pregnant in week 16 ha

Fråga: Can St John´s wort (hypericum perforatum) be used during pregnancy?

A woman pregnant in week 16 has taken St John´s wort in an unknown dose occasionally for several months.

Sammanfattning: The experience on the use of St John´s wort during pregnancy is very limited and its use cannot be recommended at present. There is, however, no data so far indicating teratogenic properties of St John´s wort.

Svar: No clinical studies addressing possible harmful effects of St John´s Wort during pregnancy could be located.

In a review from 1998 two cases were described. A 38-year-old pregnant woman started taking 900 mg/d of St John´s wort at 24 weeks and delivered a child healthy except for development of jaundice on day 5. In the other case a 43-year-old woman started taking 900 mg/d of St John´s wort during pregnancy, the outcome is not known (1).

There are two published teratogenicity studies in mice on St John´s wort (2,3). In one study, a reduced litter size and reduced fetal weight was seen in 25 mice treated with 136 mg per kg during pregnancy (2). Some weight reduction in the male offspring was seen in the other study in which mice were treated with 180 mg per kg before and throughout gestation. However, no effect on the long term growth or physical development was observed (3).

Product summaries of St John´s wort do not recommend treatment during pregnancy (4,5). 1 Burg MA, Kosch SG, Neims AH, Stoller EP: Personal use of alternative medicine therapies by health science center faculty. JAMA 1998; 280: 1563-1568 2 Gonzalez CL, Stewart JD, Rayburn WF, Christensen HD: Establishment of a relevant dose of antenatal hypericum (St John´s Wort) for neurobehavioral development study. Neurotoxicol & Teratol 1998; 20: 369 3 Christensen HD, Rayburn WF, Coleman FH, Gonzalez CL: Effect of antenatal hypericum (St John´s wort) on growth and physical development of mice offspring. Teratology 1999; 59: 411 4 Naturläkemedel 2000. Stockholm: Hälsokostrådets Förlag; 1999, p. 60-61 5 Naturläkemedel 2000. Stockholm: Hälsokostrådets Förlag; 1999, p. 65