Zofran, an anti-nausea drug commonly prescribed “off-label” to pregnant women with morning sickness, has been linked to an increased risk of heart defects, cleft palate, and other devastating birth defects.
Zofran Birth Defects
In July 2012, the Justice Department ordered GSK to pay $3 billion for illegally marketing many drugs “off-label,” including Zofran in pregnant women with morning sickness. GSK also paid kickbacks to doctors who prescribed Zofran.
This is concerning, because Zofran is “Pregnancy Category B” — meaning there are no adequate or well-controlled studies of Zofran’s safety in pregnant women. Its fetal safety data is based on fewer than 200 births.
Studied conducted by GSK in the 1980s showed that it crossed the placenta in animals. In the last decade, several studies have confirmed that Zofran rapidly passes through the human placenta in “significant amounts” and remains active in the fetus much longer than the mother.
In February 2013, the New England Journal of Medicine published a reassuring study concluding that Zofran did not increase the risk of birth defects.
However, half of the women in the study took Zofran after the 10th week of pregnancy, after their baby was no longer at risk of heart defects, cleft lip/palate, and other major birth defects.
Six months after this study was published, another team of researchers looked at the same database of pregnancy outcomes — but found that Zofran doubled the risk of having a baby with a heart defect, leading to a 30% overall increased risk of birth defects. About 5% of babies exposed to Zofran had a birth defect, compared to 3.5% of babies who were not exposed.
In 2013, a large study looked at 900,000 pregnancies and about 1,250 women who used Zofran during the first trimester. Researchers found that the risk of heart defects was about twice as high for babies who were exposed to Zofran.
In December 2014, Reproductive Toxicology published a study from Swedish researchers who looked at data on 1,400 Zofran-exposed pregnancies from 1998-2012. They found that Zofran doubled the risk of “hole in the heart” defects.
Case reports have linked Zofran to the following heart defects:
- Atrial Septal Defect (ASD): This “hole in the heart” defect allows blood to pass between the two upper chambers (atria) of the heart. Over time, large defects can cause lung damage, poor oxygen levels in the bloodstream, and lead to life-threatening complications.
- Ventricular Septal Defect (VSD): This is a hole between the two lower chambers (ventricles) of the heart. VSD is much less common than ASD, but sometimes the two defects occur in the same baby.
- Heart Murmur: This is any abnormal sound a doctor hears in a baby’s heart when using a stethoscope. Different heart defects make different noises, although many heart murmurs are harmless.
Zofran Linked to 2X Risk of Cleft Palate
The use of Zofran during pregnancy was linked to a 2.4-fold increased risk of cleft palate in a study published in Birth Defects Research in January 2012. The conclusions were based on data from about 9,000 pregnant women who participated in the National Birth Defects Prevention Study.
What is Cleft Palate?
Cleft palate is a split in the roof of the mouth. In severe cases, the birth defect involves the hard palate (roof of the mouth), soft palate (back of the throat). The opening may connect to the nose, go through the gums, and also involve a cleft lip.
What is Cleft Lip?
Cleft lip is a split in the upper lip. It is a congenital birth defect that occurs when tissue that normally forms the upper lip does not grow together. It usually happens around the 7th week of pregnancy.
Babies who are born with a cleft lip are at risk of malnutrition if they have problems feeding. They may also need multiple reconstructive surgeries within their first few years of life. With treatment, long-term prognosis is very good.
A study published by Australian researchers in December 2013 linked Zofran to a non-significant 20% increased risk of birth defects. Zofran was also linked to a 6-fold increased risk of kidney defects, although the conclusions were based on a small sample size. The defects were described as “obstructive defects of renal pelvis and ureter,” which suggests a possible risk of hydronephrosis (fluid build-up in the kidneys). Click here to read more.
Other Birth Defects Linked to Zofran
The Toronto Star published an investigation of Zofran birth defects in June 2014, reporting 20 cases of Canadian women who had a baby with a birth defect after using Zofran.
Some of these birth defects included:
- Heart defects
- Kidney malformations
- Musculoskeletal abnormalities
- Mouth deformity
- Fetal growth restriction
- Fetal death