Many antidepressants, including SSRIs, can increase the risk of birth defects if taken while pregnant.
Pregnant women suffering from depression face a difficult decision. They can risk potential harm to their babies by taking a class of antidepressants that are the current standard of treatment — or face other possible dangers to themselves and their babies if the disease is left untreated for months.
Doctors’ current antidepressant drugs of choice during pregnancy include Prozac and Zoloft. Both drugs belong to the family of drugs known as selective serotonin reuptake inhibitors (SSRIs). Drugs in this class have largely been assigned a “C” grade for safety during pregnancy by the U.S. Food and Drug Administration (FDA). That means they have been known to harm animals taking them in large doses, but because researchers cannot ethically test any drug on a human baby, the FDA states that effects on unborn humans remain unproven.
There is one SSRI that the FDA and its manufacturer warn women not to take during pregnancy — paroxetine (Paxil), which carries a grade D. Drugs that are labeled as D have been shown to be a risk to a human fetus.
Researchers have consistently raised questions about the safety of SSRIs during pregnancy. Studies linked SSRIs to low risks of serious birth defects when the drugs are taken during pregnancy.
Persistent Pulmonary Hypertension of the Newborn (PPHN)
One of the most serious birth defects linked to SSRIs is persistent pulmonary hypertension of the newborn (PPHN), a rare problem that affects a newborn’s heart and lungs. Some scientists say taking the drug during the second half of pregnancy can cause this condition.
According to the FDA, “PPHN occurs when a newborn baby does not adapt to breathing outside the womb. Newborns with PPHN may require intensive care support including a mechanical ventilator to increase their oxygen level. If severe, PPHN can result in multiple organ damage, including brain damage, and even death.”
The agency first issued a public health advisory about PPHN in July 2006 and followed up with a safety communication in December 2011, stating that the extent of the connection between SSRIs and PPHN is still being determined.
In a January 2011 product statement update, Prozac manufacturer Eli Lilly admitted there also is a risk of damage to babies’ hearts when they are in utero. Septal defects, or holes in the walls of the heart, can severely compromise blood circulation. These defects are believed to occur when a woman takes an SSRI during the first trimester of pregnancy.
“There is some evidence of a possible small increase in the risk of cardiac malformations (e.g. ventricular and septal defects) associated with use of fluoxetine. The mechanism is unknown. The use of Prozac during pregnancy should be considered only if the potential benefit justifies the potential risk to the fetus taking into account the risks associated with untreated depression,” the statement says.
The use of SSRIs during pregnancy also has been linked to neural tube defects, according to a study published in the New England Journal of Medicine in June 2007. Researchers found anencephaly, craniosynostosis and omphalocele in a higher number of babies whose mothers had ingested SSRIs one month prior to conception or while pregnant.
Defects occur during early fetal development.
Anencephaly and craniosynostosis refer to malformation of the brain and skull, and anencephaly typically results in death shortly after birth.
Omphalocele is a condition where some of the fetus’s organs, such as the intestines, stomach and liver, are extruding through a hole in the abdomen. By itself, omphalocele is quite treatable. Unfortunately, it often occurs with other birth defects.
Mothers who take an SSRI during pregnancy also risk their babies being born with facial malformations, such as cleft lip and palate, studies have shown. A cleft is the gap left when a human structure does not fully form or properly fuse together. A cleft palate, which is the result of the roof of the mouth not closing, can interfere with feeding, speech and breathing. Ear infections and hearing loss are also possible. A cleft lip occurs on the upper lip and can cause delays in speech as well as other linguistic issues.
Babies born to mothers who took an SSRI during the third trimester may experience respiratory distress at birth, or trouble breathing.
Respiratory distress syndrome (RDS) refers to a certain type of breathing problem that typically affects babies who are born prematurely. Babies could also suffer from neonatal adaptation syndrome, neonatal abstinence syndrome or neonatal withdrawal syndrome — all of which are also characterized by breathing problems.
Researchers are studying not only physical birth defects, but also the long-term neurological effects of SSRIs on fetuses. One such case study reported in the Archives of General Psychiatry in July 2011 links the use of SSRIs in the first trimester of pregnancy with increased chances of a baby developing autism spectrum disorder (ASD). Although the use of antidepressants is considered a low risk factor overall for ASD, it was attributed to about 3 percent of the cases in the population.
Unfortunately, researchers have found time and again that SSRIs easily pass through the placenta and impact the development of the fetus in serious ways, elevating the risk of a host of birth defects. The National Institute of Mental Health also reports in a March 2009 study that SSRIs can increase the risk for premature birth. It is extremely important that women, in consultation with their doctors, give serious consideration to whether the benefits of taking an SSRI during pregnancy outweigh potential risks.