Antibiotic Use May Increase the Risk of MiscarriagesMay 2, 2017
Canadian scientists conducted a research project that revealed that common antibiotics taken during pregnancy may increase the risk of miscarriages, The Times reports.
Antibiotics Pregnant Women Should Avoid
Drugs identified as presenting a higher risk include macrolides, quinolones, tetracyclines, sulfonamides, and metro-nidazole, Scientists who participated in the research found that erythromycin and nitrofurantoin, taken for urinary tract infections in pregnant women, did not raise the risk.
A greater chance of miscarriage was not seen with the most frequently used antibiotics, including penicillin, according to CNN.
National Health Service (NHS) advises that the only macrolide that should be taken during pregnancy is erythromycin. Tetracycline should not be used during pregnancy unless absolutely necessary. Fluoroquinolones, a kind of quinolone, are not normally suitable for pregnant women or women who are breastfeeding, reports The Times.
Personal injury attorneys at Parker Waichman LLP are actively reviewing potential lawsuits on behalf of individuals who have been injured by adverse side effects from pharmaceuticals, including antibiotics.
Anick Bérard, a pharmacy professor from the Université de Montréal, and the leader in the research said, "Certain types of antibiotics are increasing the risk of spontaneous abortion, with a 60 percent to two-fold increased risk." Bérard added, "Repetition of findings are essential in order to assess causality," explaining that antibiotic prescribing patterns vary from country to country, so it is important to view this research question from the perspective of a variety of patient populations.
In addition, tetracycline is not recommended in pregnancy because it permanently discolors fetuses' teeth and may affect fetal bone growth, Bérard said.
The study showed that norfloxacin, a type of quinolone, was associated with more than a fourfold increased risk. Azithromycin and clarithromycin, which belong to the macrolide class of antibiotics, were linked to a 65 percent and twofold increased risk of miscarriage, respectively. U.S. News reports.
Data was examined by the researchers from the Quebec Pregnancy Cohort from 1998 to 2009, comparing 8,702 miscarriages with 87,020 births in the control group. Participants ranged in age from 15 to 45 years old and were covered by Quebec's drug insurance plan. Of the women who miscarried, 16.4 percent (1,428 women) had taken antibiotics during early pregnancy (the first 20 weeks), compared with 12.6 percent (11,018) of the women who had not taken them, The Times reports.
The findings in this study are consistent with the results seen in some previous studies, but the association between the use of quinolones and tetracyclines and miscarriage are new findings, according to Bérard.
Danish researchers in 2013 reported a link between the antibiotic clarithromycin and miscarriage.
The result showing that quinolone and tetracycline are linked to an increased risk of miscarriage is "concordant with guidelines that say that they should not be used during pregnancy," Bérard remarked. "The take-home message is that infections need to be treated during pregnancy," she said, adding that women should consult with their health care providers for the best treatment option for an infection.
Dr. Sharmila Makhija, professor and university chairwoman in the Department of Obstetrics & Gynecology and Women's Health at Albert Einstein College of Medicine and Montefiore Health System, described the new study as "a comprehensive analysis of additional classes of commonly used antibiotics in pregnancy."
The study does not prove cause and effect. But, it does tie use of certain medicines to a higher risk of miscarriage – up to double the risk for some classes of antibiotics, the researchers noted.
The study appears in the May 1, 2017 edition of the Canadian Medical Association Journal.
According to CNN, physicians do not prescribe tetracyclines during pregnancy due to concerns over birth defects. Macrolides are frequently prescribed when penicillin cannot be used to fight streptococcal and pneumococcal infections. Suflonamides treat urinary tract infections, ear infections, bronchitis, and eye infections. Metronidazole is used to treat infections of the vagina, stomach, joint, skin, and respiratory tract.
Dr. Errol Norwitz, chairman of obstetrics and gynecology at Tufts University School of Medicine in Boston, and not involved in the study said, "Overall, it [the study] was quite well done." He added, "The best approach is to aim for the lowest effective dose using the most appropriate antibiotic."
Information and Advice Regarding Pharmaceutical Side Effects
If you or someone you know has been injured by antibiotics taken during pregnancy, you may be eligible for valuable compensation. The personal injury attorneys at Parker Waichman LLP offer free, no-obligation case evaluations. We urge you to contact us at 1-800-YOURLAWYER (1-800-968-7529).