Cranberry to treat utis safe in pregnancy study
Cranberry use may be a safe and suitable adjunct therapy for urinary tract infections during pregnancy according to research out of Norway.
Cranberry has been reported to be one of the most widely used medicinal herbs during pregnancy, however despite its popular use, there is little evidence to date on its safety or possible negative effects on pregnancy outcomes.
The primary aim of the researchers from the University of Bergen, University of Oslo and the Norwegian Institute of Public Health was to determine whether the use of cranberry during pregnancy was associated with an increased risk of malformations.
The study authors also investigated whether or not using cranberry during pregnancy was associated with negative pregnancy outcomes including stillbirth, low birth weight, preterm birth, low Apgar score, neonatal infections and maternal vaginal bleeding.
The study included data taken from the Norwegian Mother and Child Cohort Study and records from the Medical Birth Registry of Norway. A total of 68,522 pregnancies were included in the study, with 919 (1.3%) of women reporting that they had used cranberry during their pregnancy.
Urinary tract infections (UTIs) are the most commonly experienced bacterial infections during pregnancy. The total number of women in this study reporting a UTI during pregnancy was 7,311- of which 4,085 were treated with antibiotics, with 554 (60.3% of 919) women treated with cranberry- 300 of which who did not treat their UTI concomitantly with antibiotics.
Cranberry use was classified either as during pregnancy (total), early pregnancy (before 17 weeks) and late pregnancy (at and after 17 weeks pregnancy).
Among those women that used cranberry during pregnancy, 121 (13.2%) did so in their first trimester and 566 (61.6%) in early pregnancy.
In those women that experienced a UTI that was treated with cranberry (554) there were 402 in the early pregnancy group and 304 during late pregnancy.
The researchers found no increased risk of malformations in general or major or cardiac malformations in the women that used cranberry in early pregnancy.
They also found no increased risk of stillbirth, low birth weight, preterm birth, low Apgar score (<7) or neonatal infections.
The researchers said, “Our findings are reassuring, showing no increased risk of congenital malformations, stillbirth/neonatal death, preterm delivery, low birth weight, small for gestational age, low Agpar score and neonatal infections.”
“To the best of our knowledge, this is the first to study to investigate the risk of malformations after use of cranberry during pregnancy.”
They did report that there appeared to be an increased risk of vaginal bleeding in late pregnancy (at and after 17 weeks pregnancy) in women that used cranberry at this stage of pregnancy.
And while this was not considered to be significant after adjustment was made, the researchers did say that this risk could not be ruled out.
“We did not find a statistically significant association between the use of cranberry during early pregnancy and maternal vaginal bleeding or between use of cranberry during late pregnancy and more severe bleeding outcomes…... These findings are reassuring.”
“Nevertheless, a non-significant trend was seen between use of cranberry during late pregnancy and vaginal bleeding more than spotting after pregnancy week 17. Consequently, maternal vaginal bleeding is something that should be explored in later studies with respect to administration form and dosage.”
The administration form and dosage of cranberry used by the women in this study is a limitation acknowledged by the researchers. The total daily dose, frequency and duration of treatment and any other medicinal herbs taken alongside cranberry was not reported.
The researchers however, did feel that given the large sample size of the study and the widespread use of cranberry by pregnant women that their results are clinically relevant.
While there is so far a lack of evidence to support the use of cranberry in the treatment of UTIs, the authors concluded that cranberry could be a suitable adjunct therapy, when used alongside antibiotics, for the treatment of UTIs during pregnancy.
Source: BMC Complementary and Alternative Medicine 2013, 13:345 doi:10.1186/1472-6882-13-345