Antibiotics In Pregnancy – What to Have & What to Avoid


Antibiotics are the basic medications provided to treat fungal, viral and bacterial infections. Some of them are in the narrow spectrum (for example – penicillin) and treat single or several infections; whereas some are in the broad spectrum (for example – tetracycline or ampicillin) and treat a range of bacteria specific illnesses.

Why Do You Need Antibiotics In Pregnancy?

Pregnancy is a crucial time for a woman as she undergoes a lot of changes within her body. It brings with it vulnerability to infections which may need to be treated with antibiotics, as leaving the illness untreated poses a risk to the baby’s health. One should remember that use of antibiotics during pregnancy may sometimes prove more beneficial than harmful, so it can be prescribed even in the third trimester for a short effective duration. It is important that one does not self-medicate and consults a doctor before using an antibiotic.

Are Antibiotics Safe In Pregnancy?

Antibiotics vary in terms of the risk they pose during pregnancy. There are some antibiotics that can cause harm to the mother as well as the foetus and are not safe to be used. You should acutely analyse the effects of the prescribed antibiotics, weigh the benefits, and take the medication only if no other alternative drug exists.

  • How Safe Are Antibiotics During Pregnancy?

It is important to bear in mind that pregnant women who do not treat their illness may pose a higher risk for the newborn. Besides, side effects of any medication largely depend on the amount of medicine consumed, the span of time for which it is taken and the stage of pregnancy.

  • How Is The Safety Of Antibiotics Ascertained?

Antibiotics are essential and have been used in pregnancy safely for years. The Food and Drug Administration (FDA) rates certain antibiotics in categories of A, B, C, D and X, based on its safety during pregnancy. Medications under A and B are usually contemplated to be safe for pregnant women. In 2011, the committee of American Congress of Obstetricians and Gynaecologists (ACOG) validated the safety of antibiotics that are commonly prescribed in pregnancy. The conclusions were drawn based on:

  • Investigations conducted on lab animals
  • Studies on women using antibiotics and showing low risk of birth defects
  • Several years of use of antibiotics in obstetrics

List Of Antibiotics Safe In Pregnancy

In pregnancy, antibiotics should be used only when prescribed by the doctor. It is important to consult a medical professional to ascertain what antibiotics are safe during pregnancy.

As per ACOG, safe antibiotics include the following:

  • Penicillin
  • Amoxicillin
  • Oxacillin
  • Ampicillin
  • Keflex
  • Ancef
  • Rocephin
  • Gentamycin
  • Neomycin
  • Nitrofurantoin
  • Clindamycin
  • Cephalexin

Antibiotics To Avoid In Pregnancy

While antibiotics may be essential in some situations, is important to be aware that they may have harmful side effects and may interfere with the body’s ability to fight illness. During pregnancy, some antibiotics affect the baby in the first and third trimesters, while some have their effect throughout pregnancy.

Some Antibiotics Are Best Avoided In Pregnancy

The following antibiotics are classified under category D, as unsafe for pregnancy:

  • Streptomycin and Kanamycin cause damage to the auditory nerve, leading to hearing loss in new-born.
  • Tetracycline, Minocycline, Doxycycline and Oxytetracycline cause discolouration of baby’s teeth.
  • Sulphonamide interferes with bile metabolism and transport in the baby’s liver and may also cause neonatal jaundice.
  • Macrobid and Macrodantin affect the baby’s red blood cells.

Common Infections During Pregnancy

The most common infections faced during pregnancy that require a certain level of antibiotic treatment are:

  • Vaginal Infections– Metronidazole is used to cure vaginal infections such as bacterial vaginosis and trichomoniasis. Earlier it was believed to cause congenital birth defects but was later declared safe.
  • Urinary tract infection– This is a common condition faced by pregnant women. Antibiotics for urinary tract infection during pregnancy are:
  1. Nitrofurantoin (also termed Macrobid / Macrodantin) – recommended until 36 weeks of pregnancy as later it may adversely affect the foetus’s red blood cells
  2. Trimethoprim (also termed Bactrim / Septa) – it often interferes with the absorption of folic acid and may cause a neural tube defect in the baby. It is recommended to be taken with a daily prenatal vitamin and a folic acid supplement, to cover the loss.

Precautions To Take While Having Antibiotics In Pregnancy

Researchers advise pregnant women to follow certain guidelines while taking an antibiotic. The following precautions are advisable for ensuring better health of the mother and baby:

  • Use An Antibiotic Only If No Alternate Treatment Suffices

Antibiotics are generally not recommended during pregnancy except for some serious illness.

  • Choose Single Prescriptions Over Polypharmacy

Avoid combination medicines that are known to cure several symptoms at a go. As per research, such drugs often result in hypertension or high blood pressure in pregnant women.

  • Do Not Treat Viral Infections With Antibiotics

Antibiotics are ineffective in viral infections. Besides, overuse of antibiotics leads to drug-resistant bacteria, making them ineffective in the future.

  • Avoid Antibiotics During The First Trimester

Babies are most vulnerable during the first trimester when their organs and tissues are developing

  • Start With Lowest Possible Effective Dose

Low dosage helps minimise drug accumulation and toxicity in the infant.

Make Sure You See A Doctor

  • Do Not Use Over The Counter Medications During Antibiotic Treatment

Many over-the-counter medicines are not well tested for safety of pregnant women. Do consult a doctor before taking any OTC medicine, vitamin or supplement.

  • Choose Safer Medication

Use proven and tested antibiotics (preferably tested on pregnant women)

Self-medication in any situation is best avoided, and this is especially true when one is pregnant. Make sure you see a doctor for any ailment and only use medicines prescribed to ensure a smooth pregnancy and to protect your baby.