A new study reveals that common over-the-counter antibiotics are increasing the number of pregnancy miscarriages. These antibiotics include macrolides, quinolones, tetracycline, sulfonamides, and metronidazole. 

On the contrary, per Science Daily, the research noted that erythromycin was not associated with increased miscarriage risks nor was nitrofurantoin. The drugs are used to treat urinary tract infections in pregnant women. Dr. Anick Bérard, a Pharmacy faculty at the Université de Montréal, noted that infections are really prevalent during pregnancy. Thus, mothers should be very careful about what they take during pregnancy to ensure the safety of both the carrier and the baby. The research was published in the "Canadian Medical Association Journal".

Bérard explained that while antibiotic use has been associated with a decreased rate of prematurity and low birth weight, their findings show that particular drugs upsurge the threats of spontaneous abortion. The risks were up by 60 percent to even a two-fold in some cases. The team based the study on the data from the Quebec Pregnancy Cohort between 1998 and 2009.

In it, 8, 702 cases, defined as clinically detected spontaneous abortions, were cross-examined with 87, 020 controls. The mean gestational age at the time of the miscarriage was 14 weeks. Eventually, the experts concluded that 1, 428 (16.4 percent) of the cases were exposed to antibiotics during early pregnancy compared to 11, 018 (12.6 percent) in controls.

On the other hand, USA Today reported that the ages of the samples were between 15 and 45 years old. Other findings reveal that women who miscarried were most likely to be older, living alone, and have multiple health issues and infections. The author also stressed that the baseline risk can go as high as 30 percent.

Nevertheless, the increased risk was not observed for all antibiotics. Now, this is reassuring for users, prescribers, and policy-makers. At the end of the day, health experts may update guidelines for treatment of infections during pregnancy using the results of this study.