A new study suggests that high-dose vitamin D supplementation may not help to prevent repeat bacterial vaginosis, a vaginal infection that is particularly common in younger women.
The findings counter past studies that suggested higher vitamin D levels could boost the immune system as it tries to fight off the infection.
"Earlier studies observed that women with low vitamin D levels were more likely to have bacterial vaginosis, and we hypothesized that vitamin D supplementation might reduce BV," study author Abigail Norris Turner, an infectious disease expert at the Ohio State University Wexner Medical Center, said in a university news release.
"However, our study found that high-dose vitamin D supplementation wasn't helpful in preventing recurrence of BV," she added.
Bacterial vaginosis is caused by an imbalance in the bacteria that normally populate the reproductive tract. Antimicrobial treatment is usually successful at first, but many women go on to have repeat occurrences of BV.
Bacterial vaginosis is not sexually transmitted.
Still, BV has much more serious health implications. In pregnant women, it can cause spontaneous abortions, and women who have bacterial vaginosis are more susceptible to acquiring and transmitting the human immunodeficiency virus (HIV) wrote ScienceDaily.com.
According to the study researchers, an estimated 21 million women are diagnosed with BV in the United States each year, stated HealthDay News
In the study, 118 women with bacterial vaginosis were randomized into two equal-sized groups, with one group receiving vitamin D3, and the other receiving a placebo.
All of the women were treated for BV with 500 mg of oral metronidazole twice daily for a week.
Of these women, 59 were also given nine doses of 50,000 IUs of cholecalciferol (vitamin D3) over 24 weeks. Those in the control group received a matching placebo. All of the women were assessed for recurrent BV at four, 12, and 24 weeks.
Turner found that while women randomized to the vitamin D group had significant increases in their serum vitamin D levels compared to women in the placebo arm, this did not translate into a decrease in recurrent BV.
It is worth noting a couple of potential weaknesses in this study. The study size was small, only 118 participants, so results could be different in a much larger group.
In addition, OBGyn.net reported that while the vitamin D dose given to participants in the study was high, the threshold of vitamin D blood levels may not have been high enough to make a difference clinically.
The authors agree that a higher target level may be more fitting and thus prove to make an impact on preventing recurrent BV. The challenge, they added, is that there is significant debate about the appropriate dose, schedule, and target of serum 25-hydroxy vitamin D levels for optimal health.
Turner also emphasized that while vitamin D may not be useful for treating women with recurrent BV, the jury is still out on the vitamin's ability to prevent bacterial vaginosis from initially developing.
The study was recently published in the American Journal of Obstetrics and Gynecology.
"High-dose Vitamin D Not Effective for Helping Women with Repeat Reproductive Tract Infections." ScienceDaily. ScienceDaily. Web. 19 Nov. 2014.
"High-Dose Vitamin D Not Effective for Helping Women with Repeat Reproductive Tract Infections." High-Dose Vitamin D Not Effective for Helping Women with Repeat Reproductive Tract Infections. Web. 19 Nov. 2014.
Dotinga, Randy. "Vitamin D May Not Prevent Return of Women's Infection After All." Consumer HealthDay. Web. 19 Nov. 2014.
"Vitamin D and Recurrent Bacterial Vaginosis." OBGYN.net, an Online Community for Medical Professionals. Web. 19 Nov. 2014.
Reviewed November 20, 2014
by Michele Blackberg RN
Edited by Jody Smith