Use of complementary and alternative medicines associated with a 30% lower ongoing pregnancy/live birth rate during 12 months of fertility treatment.

BACKGROUND: There seems to be little discussion between patient and physician about the use of complementary and alternative medicines (CAMs), perhaps because they are not perceived to have adverse effects on fertility. We therefore compared ongoing pregnancy and live birth rate in spontaneous users and non-users of CAM during a 12-month period of assisted reproduction technique (ART) treatment. Consent was by questionnaire return.
METHOD: This was a prospective observational cohort study with a 12-month follow-up period, sampling consecutive patients attending five ART clinics in Denmark. N = 728 women about to have ART for the first time completed self-report assessments prior to treatment (Time 1, T1) and at 12-month follow-up (Time 2, T2). Data from treatment records were also available for n = 590.
RESULTS: About 30.6% (n = 223) of women used CAMs during the observation period. At T2 the ongoing pregnancy and live birth rate was 31.3% lower in CAM users (42.2%) compared with non-users (61.4%). Adjusted odds of pregnancy/live birth remained lower in CAM users versus non-users, odds ratio = 0.467 (95% confidence interval 0.306-0.711) after controlling for prognostic indicators (age, parity, years infertile).
CONCLUSIONS: Concurrent use of CAM during treatment with ART was associated with a 30% lower pregnancy rate that could not be explained by poor prognosis or life style factors. The mechanisms that could account for this association were discussed. Concurrent CAM use should be monitored during ART. A main limitation was that we could not ascertain which type of CAM was most associated with lower pregnancy rates.