Taking Trimethoprim While Pregnant Can Cause Spina Bifida And Other Birth Defects

Trimethoprim-sulfamethoxazole is a commonly prescribed antibiotic for urinary tract infections (UTI), community-acquired methicillin-resistant Staphylococcus aureus (MRSA) and other bacterial infections including ear infections, bronchitis, traveler’s diarrhea and pneumonia. Bactrim, Septra, Trimpex, Proloprim, and SMX-TMP, sometimes called cotrimoxazole, are a few drugs that include trimethoprim.

All women of childbearing years or those desiring to become pregnant or who are already pregnant are instructed to take 400 micrograms of folic acid each day to help prevent neural tube defects, spina bifida and other serious birth defects. Trimethoprim interferes with the metabolism or absorption of folic acid so any woman who is prescribed an antibiotic with trimethoprim in it is at risk for not having the proper recommended levels of folic acid for themselves or their developing fetus. A recent study showed that the use of trimethoprim or other medications that interfere with folic acid absorption, during the first trimester or first three months of pregnancy increases the likelihood of having a child with birth defects. Some of the more common birth defects that have been linked to trimethoprim are:

  • Spina Bifida - a condition where the neural tube does not close properly and the spinal cord is on the outside of the body that could lead to permanent nerve damage or paralysis in the lower extremities or legs.
  • Anencephaly - a condition where the neural tube does not close to form the brain and spinal cord that results in the absence of certain parts of the skull, brain and scalp. A baby with anencephaly will either be stillborn or not survive long after birth.
  • Cleft Lip or Cleft Palate - a condition where there is an opening in the roof of the mouth and incomplete formation of the upper lip.
  • Polydactyly - a condition where there is more than 5 fingers or toes on each foot or hand.
  • Hypospadias - a condition where there is a defect in the urethra and the opening is on the bottom of the penis.
  • Heart Defects
  • Short bones or limbs
  • Urinary tract defects or malformations

Trimethoprim should also be avoided if a mother is breast feeding because it is excreted in the breast milk. Trimethoprim that is passed onto an infant while nursing and can cause an elevated bilirubin level (jaundice) and cause kernicterus, or permanent brain damage and cerebral palsy.

Any woman who is pregnant or at risk of becoming pregnant should not be placed on trimethoprim to treat a urinary tract infection (UTI) or other infection unless the benefits clearly outweigh the risks. If you were placed on trimethoprim while you were pregnant and your baby was born with spina bifida or other serious birth defects, please feel free to contact one of our experienced dangerous drug lawyers, doctors or nurses online or (215) 866-2424 for a strictly confidential and free consultation.