Dog Rose for the Prevention of Postpartum Urinary Tract Infections

Urinary tract infections (UTIs), inflammatory responses of squamous urinary tract tissue to bacteria, are divided into asymptomatic bacteriuria and symptomatic UTIs including cystitis and pyelonephritis. Higher risks of UTIs exist for pregnant and post-partum women, elders, children, and patients with spinal cord injury, catheterization, AIDs or HIV, or underlying urological disorders. Among post-partum women, the prevalence of UTIs for 40 days following delivery range from 3-17%. Endogenous or exogenous factors may cause UTIs, with catheterization during Caesarean section (CS), a major exogenous risk. A systematic review reported that restricting unindicated catheterization reduced incidence of UTIs by 53%. The prevalence of CS in Iran is on average three times that of other countries. It has been recommended that all women undergoing CS be given prophylactic antibiotics. Herbal medicines may offer alternatives. Dog rose (Rosa canina, Rosaceae) fresh fruit (rosehip) has about 880 mg/100 mL antioxidant vitamin C and total phenolic content of about 96 GAE/g dry weight. Dog rose also contains several minerals. Its antibacterial activity is mostly attributed to the flavonoid quercetin. Quercetin inhibits bacteria including Escherichia coli, the most common UTI agent. This triple-blinded, randomized, placebo-controlled trial (RCT) is the first of the effects of dog rose on the incidence of post-partum UTI in women who have undergone CS.

Researchers recruited 400 women between August 2016 – March 2017 at Alzahra and Taleghani hospitals (Tabriz, Iran). A sample size of 190 for each group, needed for 80% power, was raised to 200 to allow for 5% withdrawals or sample loss. Women who underwent CS were evaluated in the post-operative period. Those who met initial criteria (including catheterization during CS) and agreed to participate provided urine samples for culturing. Those with negative culture results were included and their socio-demographic characteristics recorded in an interview. They were randomized to intervention (dog rose) and control (placebo) groups. Dog rose fruit obtained from a local herb market was ground into a powder, with 500 mg placed in capsules; identical placebo capsules were filled with starch. The microbial content of fruits was eradicated by heating. No samples contained E. coli or Salmonella spp. Dog rose capsules were standardized in terms of total phenolic compounds, but the process of standardization is not described. Total flavonoids in the ground powder were measured via ultraviolet spectroscopy; ascorbic acid (vitamin C), methods of the Association of Official Analytical Chemists (AOAC). Assigned capsules were taken orally twice daily (one after breakfast and one after the evening meal) with water beginning 48 hours after CS and continuing for 20 days. Twenty instead of the more common post-partum observation period of 40 days was used to minimize withdrawals and increase complete use of medications.

Urine samples were taken on days seven to 10 and day 20 post-CS. Participants also provided information about any adverse effects (AEs), degree of satisfaction with their treatment, and any urinary symptoms. They were told to contact a researcher and seek health care if they noticed symptoms of cystitis or pyelonephritis between visits. Those whose urine cultures revealed asymptomatic UTI were seen by a gynecologist and given antibiotics; they continued to take their assigned capsules for the remainder of the study period. The groups were compared in terms of total incidence of UTIs, asymptomatic bacteriuria, cystitis, and pyelonephritis. P < 0.05 was considered statistically significant. On days seven to 10, 193 women in the intervention group and 195 in the placebo group gave urine samples; on day 20, 184 in the intervention group and 189 in control. Sixteen in the intervention group and 11 in control did not complete the study. Checklists from all completers showed that they had taken all medications.

At baseline, there were no significant differences between groups in pregnancy and childbirth histories or sociodemographic factors except spouse’s education (P > 0.05). Of 400 women, 245 had histories of CS; for >82%, CS was considered non-elective. Of those with previous CS, >22% had postoperative UTI. Of the entire sample, 98% had epidural anesthesia. Mean age was 30 ± 5.8 years; mean body mass index, 26.5. At seven to 10 days post-CS, four women in the intervention group and 13 in the placebo group had positive urine cultures (asymptomatic UTI; odds ratio [OR] = 3.37; 95% confidence interval [CI] 1.08 – 10.54; P < 0.001). At 20 days, three from the dog rose group and 19 from placebo had positive cultures (OR = 6.74; 95% CI 1.96 – 23.19; P < 0.001). Most of those with asymptomatic UTIs had cultures positive for E. coli; four, for Enterobacter cloacae; and two, Enterobacter spp. aerogenes. On day 20 post-CS, 20 from each group had cystitis with no significant difference between them. During follow-up, no participants had pyelonephritis. Total risks of UTI on days seven to 10 (OR = 0.22; 95% CI 0.01 – 0.67) and day 20 (OR = 0.32; 95% CI 0.14 – 0.75) post-CS were significantly lower in the dog rose group than in control (P = 0.008). Eight women reported mild AEs including nausea and vomiting (1), dizziness (1), rashes (4) and headache (2). They included five from the dog rose group and three from control. In both groups, 85% expressed total satisfaction with the treatment they received, with 13% relatively satisfied and 2% completely dissatisfied.

Other clinical studies of the effect of vitamin C supplementation on the incidence of UTIs have had conflicting results in different populations but most of them, as well as in vitro studies, tend to support this RCT’s results. Dog rose fruit powder has also been studied in osteoarthritis and irritable bowel syndrome, both with positive results. Given this RCT’s findings, it is likely that the administration of dog rose powder can reduce UTIs following CS. Longer studies with more frequent follow-up visits are urged.


Seifi M, Abbasalizadeh S, Mohammad-Alizadeh-Charandabi S, Khodaie L, Mirghafourvand M. The effect of Rosa (L. Rosa canina) on the incidence of urinary tract infection in the puerperium: a randomized placebo-controlled trial. Phytother Res. January 2018;32:76-83. doi: 10.1002/ptr.5950.