Use of SSRIs (Antidepressants) During Pregnancy
Medications often have long lists of side effects associated with their use and antidepressants are no exception. When a person is taking medications during pregnancy, the side effects are particularly concerning – especially when it comes to the effect of those medications on the developing fetus. A variety of birth defects have been found in pregnancies where there was use of antidepressants called SSRIs.
Selective Serotonin Reuptake Inhibitors (SSRIs)
This class of antidepressants is the most widely prescribed variety that is used in several countries throughout the world. It is thought to work by inhibiting the reuptake of serotonin in chemical synapses found in the brain. This means that serotonin stays present in the brain for longer periods of time and alleviates cases of major depression by making this “feel good” neurotransmitter present longer. These medications do cross the placenta, which enables them to have an effect on the developing fetus. In fact, SSRI levels in the umbilical cord are the same as those found in the maternal system1.
Omphalocele is a birth defect where some of the baby’s abdominal organs protrude from an opening in the area of the belly button. The organs are covered only with a thin layer of protective skin. This birth defect is a form of hernia where the abdomen has either ruptured or never fully closed during the development of the fetus.
Some studies have found that the use of some SSRIs has been associated with an increased risk of 2.8 times greater occurrence of omphalocele2. This condition is treatable through surgical intervention, which replaces the expelled organs into the abdominal area when the infant is larger. However, this condition also often occurs in conjunction with other birth defects.
Heart defects are often an extremely troubling congenital defect. A Swedish study found a greater risk of all different kinds of congenital heart defects for newborns exposed to SSRIs called paroxetine (such as Paxil)3. This particular study did not find any associated risk of cardiac birth defects with exposure to other classes of SSRIs although other studies have2. Specific heart defects found to increase with use of SSRIs in this study include conotruncal heart defects and septal heart defects. These results were even more pronounced when obese mothers who took SSRIs were examined separately.
Neonatal Abstinence Syndrome
Neonatal abstinence syndrome is found in newborns who are suffering from withdrawal symptoms at birth. This syndrome can include seizures, tremors, high pitched crying, fever and feeding problems. Adults who have stopped taking SSRIs can suffer from withdrawal symptoms as well and are usually slowly weaned off of these medications. Infants do not have this same ability for a slow weaning. Since 2005, this syndrome has been found to be present in at least 93 different babies with SSRI exposure, according to a study published by the Lancet4.
Persistent Pulmonary Hypertension
This is an extremely dangerous and life threatening condition found in newborns that limits the amount of oxygen in the bloodstream. In this condition, the lung vessels have high blood pressure, which causes them to constrict. This constriction limits the blood flow to the lungs and the flow of oxygen into the blood stream. Treatment usually requires intensive care, intubation and artificial respirations, and proves fatal between 10 and 20 percent of the time it is diagnosed.
One study has found persistent pulmonary hypertension to be six times more common in babies exposed to SSRIs after the 20th week of gestation5. However, this study is controversial, because the findings have not been replicated and the sample size was extremely small.
There are a number of birth defects that have been associated with the use of SSRIs during pregnancy. However, it is important to keep in mind that there are risks associated with not treating depression during pregnancy as well. In fact, un-medicated mothers have been found to have poor prenatal health habits and less favorable pregnancy outcomes in general6. The decision on whether or not to medicate should be made by the woman and her doctor.
- Loughhead AM et al. Placental passage of tricyclic antidepressants. Biol Psychiatry 2006 Feb 1; 59:287-90.
- Alwan; Reefhuise; Rasmussem; Olney and Friedman. Use of Selective Serotonin Reuptake Inhibitors in Pregnancy and the Risk of Birth Defects. The New England Journal of Medicine 2007 June 28; 356:2684-2692.
- Kallen B, Otterblad Olausson P. Maternal Use of Selective Serotonin Re-uptake Inhibitors in Early Pregnancy and Infant Congenital Malformations. Birth Defects Res A Clin Mol Teratol 2007; 79:301-308.
- Sanz, Emilio et al. Anti-depressants used during pregnancy linked to neonatal withdrawal syndrome. Medical news Today – Lancet Press Release. 2005 Feb 05.
- Chambers, Christina et al. The New England Journal of Medicine. 2006, Feb 9.
- Bonari, Lori et al. Perinatal Risks of Untreated Depression During Pregnancy. Canadian Journal of Psychiatry. 2004 Nov; 11:726-735.