If you’re pregnant and find yourself endlessly scrolling through online forums, you’re not alone. Not by a long shot.

With so many dos and don’ts in pregnancy, it’s understandable if you’re not totally sure what’s what. But there’s one question in particular that we’ve seen come up a lot: Can boric acid cause miscarriage?

The short answer is… probably not. But that doesn’t make boric acid safe for pregnancy. Here’s what you need to know.

woman doing research about boric acid and pregnancy

What is boric acid?

Boric acid is a white power used in hundreds of over-the-counter products, from soil fertilizers to personal care products. It’s derived from the natural element boron. Boric acid’s use in a wide array of products stems from its antifungal and antimicrobial properties.

Boric acid suppositories are an over-the-counter treatment that can help with yeast infections and bacterial vaginosis (BV). When the balance of “good” versus “bad” bacteria in the vagina is thrown off, this also disrupts the vagina’s acid balance. Boric acid suppositories work by adjusting the vagina’s level of acidity.

Although boric acid suppositories have demonstrated effectiveness for treating vaginal conditions, they’re not FDA-approved because they’re supplements. This means there’s no way to know for sure that every boric acid suppository is as effective as others.

boric acid suppository

Can using boric acid cause miscarriage?

According to OB/GYN Cordelia Nwankwo, MD, FACOG, “There is no data showing an association between boric acid and risk of miscarriage.” 

There is mixed evidence that another fluconazole (Diflucan), another commonly used treatment for yeast infections, may increase the risk of miscarriage. But, to our knowledge, there is no comparable research investigating the link between boric acid and miscarriage.

So… is boric acid safe during pregnancy?

The American College of Obstetricians and Gynecologists (ACOG, the leading body of OB/GYNs) advises against using boric acid vaginal suppositories during pregnancy. This is because human data, although limited and often poorly collected, shows a possible association between boric acid and fetal malformations or defects. In animal data, high levels of boric acid taken orally have been linked with adverse fetal outcomes. There are no similar studies for intravaginal boric acid use in pregnant animals.

So, while the jury is out on the exact effects of boric acid use in pregnancy, the safest path is to follow ACOG’s guidelines and avoid it altogether.

Important note: Taking boric acid by mouth can be very dangerous, whether you’re pregnant or not. Never take boric acid orally.

woman doing research about boric acid and miscarriage

What can pregnant people use instead of boric acid?

Some vaginal infections, like bacterial vaginosis (BV), may increase the likelihood of preterm labor. While yeast infections aren’t likely to impact pregnancy or birth outcomes, they’re uncomfortable regardless of pregnancy. Thankfully, some medications are safe to take during pregnancy for both conditions.

Dr. Nwankwo recommends that her pregnant patients take metronidazole (aka Flagyl) orally or vaginally for BV. For pregnant patients with yeast infections, she recommends over-the-counter or prescription azole creams (e.g., Monistat 7-Day Treatment). 

If you’re experiencing uncomfortable vaginal symptoms, whether you’re pregnant or not, talk to your healthcare provider as a first step. Since many supplements, like intravaginal boric acid, aren’t safe during pregnancy, it’s best to get their advice before starting any sort of treatment regimen.

Sarah duRivage-Jacobs is a sexual and reproductive health writer, educator, and communicator. In addition to Rescripted, her words can be found on the blogs of reproductive health and mental health companies like Modern Fertility, Hey Jane, Millie, Carrot, Origin, O.school, and Charlie Health. You can visit her website here.