Nitrofurantoin
and trimethoprim-sulfamethoxazole were commonly prescribed for pregnant women
during first trimester in 2014, despite the potential risk associated with these
antibiotics, reports the results of analysis of large insurance database by Center
for Disease Control(CDC). These findings were reported in the Morbidity and Mortality Weekly Report(MMWR) by CDC issued January 12, 2018.
Pregnant
women are routinely screened for UTI in pregnancy and receive antibiotics if
they screen positive, because of foreseen serious complication later in pregnancy
like pyelonephritis, preterm labor, low birth weight, and sepsis.
ACOG recommends
to being selective in prescribing antibiotics during first trimester because of
potential of birth defects with certain antibiotics. ACOG recommends that nitrofurantoin
and trimethoprim-sulfamethoxazole should only be prescribed in early pregnancy
when other antibiotics are found ineffective.
CDC gathered
data of about 482,917 pregnancies from Truven Health MarketScan Commercial
Database and analyzed it for prescription filled for antibiotics during the
first trimester.
All pregnant
women between aged 15–44 years with a diagnosis of a UTI from 90 days
before LMP through the end of pregnancy were identified to be included in
the study. UTI was defined according to the International Classification of
Diseases Ninth Revision, Clinical Modification (ICD-9 CM) diagnosis code or presence of cystitis with
an outpatient prescription filled.
Women with
recurrent UTI or those who were admitted were excluded from study.
The data
showed that 34,864 (7.2%) pregnant women had an initial outpatient UTI claim 90
days before or during pregnancy. UTI was most common during the first
trimester (40%) and least common in the third trimester of pregnancy.
Types of
antibiotics prescribed differed according to pregnancy status of women, with fluoroquinolones
and sulfonamides more commonly prescribed to women within 90 days before their
LMP while nitrofurantoin, cephalosporins and penicillins were the drugs of
choice during pregnancy.
The most
common antibiotics prescribed during the first trimester were nitrofurantoin
(34.7%), ciprofloxacin (10.5%), cephalexin (10.3%), and
trimethoprim-sulfamethoxazole (7.6%).
This report
has its own limitations because UTI was identified only based on codes and not
lab reports, some women may have other concomitant infections for which these
antibiotics were prescribed, the MarketScan sample was a convenient sample
hence could not be generalized to whole of US populations and out of pocket
payee women were not included in the study.
Inspite of these
limitations, the report shows that it is
important for all healthcare providers to be aware of antibiotic recommendations
in pregnancy and be aware that they are prescribing for two in women who are
pregnant or who might get pregnant in coming months.
