en Clinical Medicine Clinical Medicine مقاله پژوهشی Original Research Article <span style="font-size:12pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">Background:</span></span></span></span></b></span></span></span><span style="font-size:12pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">Bacterial vaginosis (BV) is one of the most frequent vaginal infections and has been linked to unfavorable reproductive outcomes. </span></span></span></span><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif">Vitamin D is known to play a key role in regulating immune function<b>, </b>and its deficiency has been proposed as a potential factor that may increase vulnerability to BV<b>.</b></span></span></span></span></span></span><br> <br> <span style="font-size:12pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">Methods:&nbsp;</span></span></span></span></b><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">This systematic review analyzed studies published up to September 2023 using both national and international databases. Relevant keywords, including&nbsp;<i>bacterial vaginosis</i>,&nbsp;<i>vitamin D</i>, and&nbsp;<i>25-hydroxyvitamin D</i>, were used in English and Persian searches. </span></span></span></span><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif">The methodological quality of the included studies was evaluated using the Newcastle&ndash;Ottawa Scale and the Jadad checklist<b>.</b><span style="color:black"></span></span></span></span></span></span></span><br> <span style="font-size:12pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">Results:</span></span></span></span></b><br> <span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif">A total of seven studies met the inclusion criteria<b>.</b> <span style="color:black">The overall methodological quality ranged from moderate to high. </span>Approximately half of the studies reported a significant association between lower serum vitamin D levels and BV, while the remaining studies did not observe a statistically meaningful relationship.</span></span></span><span style="font-family:&quot;Times New Roman&quot;,serif"></span></span></span></span><br> <span style="font-size:12pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><b><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:black">Conclusion:&nbsp;</span></span></span></span></b><span style="font-size:14.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif">Current evidence indicates a possible link between vitamin D status and bacterial vaginosis; however, the findings are not consistent across studies<b>.</b> Further well-designed prospective studies and randomized controlled trials are needed to clarify the role of vitamin D in the prevention and management of BV. <span style="color:black">Future research should also explore the effects of vitamin D on the vaginal microbiome, particularly in asymptomatic women.</span></span></span></span></span></span></span><br> &nbsp; Vitamin D, Bacterial Vaginosis, Serum 25-Hydroxyvitamin D, Systematic Review, Non-Pregnant Women, Vaginal Microbiome 30 30 http://journal.zums.ac.ir/browse.php?a_code=A-10-7177-4&slc_lang=en&sid=1 Afsaneh Talebi Talebia@tutamail.com 5200319475328460089050 5200319475328460089050 No Setareh Yousefi Yousefis@tutamail.com 5200319475328460089051 5200319475328460089051 No Mahnaz Azari Azarim@tutamail.com 5200319475328460089052 5200319475328460089052 No Tannaz Jamialahmadi jamiat931@gmail.com 5200319475328460089053 5200319475328460089053 No Amirhossein Sahebkar amir_saheb2000@yahoo.com 5200319475328460089054 5200319475328460089054 Yes