New Research Ties Antidepressant Use in Pregnancy to Preterm Birth
Date: March 2014
Publication: PLoS One
Drugs: SSRI and SNRI antidepressants
A comprehensive review of 41 studies confirms previous findings of a significant link between maternal antidepressant usage and preterm birth. Researchers at Harvard Medical School, Vanderbilt University and Tufts University School of Medicine found that antidepressant usage at any time during pregnancy increased the risk of preterm birth by 61%, even after adjusting the figures for the possible influence of depression itself. Mothers who used antidepressants during the third trimester doubled their risk of having a preterm birth.
A thorough search of medical databases turned up 41 studies published between 1993 and 2012 that compared preterm birth rates in women who took antidepressants during pregnancy, with rates for women who did not take antidepressants. A comprehensive review of the research literature on antidepressants and preterm birth by scientists at Harvard Medical School, Vanderbilt University and Tufts University School of Medicine has provided strong confirming evidence that maternal antidepressant usage during pregnancy significantly increases a mother’s risk of having a preterm birth.
A thorough search of medical databases turned up 41 studies published between 1993 and 2012 that compared preterm birth rates in women who took antidepressants during pregnancy, with rates for women who did not take antidepressants. SSRI and SNRI antidepressants were the primary drugs analyzed in all the studies. Preterm birth was defined as birth before 37 weeks’ gestation. The studies were grouped into those that adjusted their findings for the potential influence of various “confounders” (factors other than antidepressants that have also been associated with preterm birth, including maternal age, smoking, alcohol use, and history of prematurity or miscarriage and those that did not. A third group comprised studies that adjusted for the possible confounding effect of maternal depression or psychiatric illness.
“…[O]ur study findings … reinforce the notion that antidepressants should not be used by pregnant women in the absence of a clear need that cannot be met through alternative approaches.”
Pooling the data from the studies that did not adjust for confounders yielded a 57% increase in risk of preterm birth following antidepressant use early in pregnancy (typically 1st trimester usage) and a 44% increase in risk tied to use any time during pregnancy.
After pooling data from studies that did adjust for potential confounders, the researchers found that early exposure to antidepressants increased the risk of preterm birth only slightly (the association was not statistically significant), whereas usage any time during pregnancy increased the risk by 53% and late exposure (typically 3rd trimester) nearly doubled the risk (96% increase).
Eleven studies attempted to separate the effects of antidepressants from the possible confounding influence of depression or behaviors that might be associated with depression, such as smoking or alcohol intake. The authors report, “Most of these 11 studies nonetheless found an increased risk of preterm birth associated with antidepressant medication use….” The pooled data from these studies demonstrated a 61% increase in risk of preterm birth for antidepressant users compared to women with psychiatric illness but no antidepressant use.
Additional mathematical testing (called sensitivity analysis) demonstrated that the association between antidepressant use and preterm birth found by the investigators was quite strong. In other words, it was unlikely that the findings were the result of confounding that the scientists had not properly measured.
The authors stressed that even “moderate (32 to 33 gestational weeks) and mild (34 to 36 gestational weeks) preterm birth infants are also at increased risk for neonatal and post-neonatal mortality and morbidity,” including “health problems ranging from neurodevelopmental disabilities such as cerebral palsy and mental retardation to other chronic health problems such as asthma.” They also observed that the evidence linking depression itself to preterm birth is “weak.”
SSRI Antidepressants More than Double the Risk of Lung Complication in Newborns
Date: January 14, 2014
Publication: British Medical Journal
Drugs: SSRI antidepressants
In this meta-analysis, researchers pooled data from seven previous studies that had investigated the relationship between maternal use of SSRI antidepressants and a serious condition in newborn babies known as persistent pulmonary hypertension of the newborn (PPHN). Each of the studies chosen by the investigators was selected for the high quality of its study design. The study was published online on January 14, 2014 in the British Medical Journal.
The time of exposure to SSRIs was divided into four categories: exposure in early pregnancy; at any time in pregnancy; during most or all of the pregnancy; and during late pregnancy. Studies varied in their definitions of early and late pregnancy, but early pregnancy generally meant from ninety days before pregnancy up to fifty-five days into the pregnancy, or before week twenty. Late pregnancy meant during or after week twenty, or during the third trimester.
The investigators reported an increased risk for newborns exposed to SSRIs late in pregnancy that was two and a half times greater than non-exposed babies. However, after adjusting their results for potential publication bias (the selective publishing of only studies with positive results) the authors estimated that late exposure to SSRIs increased the risk of PPHN 2.84 times, nearly triple the risk of babies not exposed. The risk for babies who were exposed “most or all of pregnancy” was estimated to be even higher: 3.3 times the risk.
Exposure was primarily determined by prescription registries, but such registries can only tell investigators if a drug was prescribed, not if it was taken. According to the investigators, “the pool effects were dominated by the registry studies, and yet we cannot be confident that the mothers used the drugs as prescribed.” Scientists in one study found that estimates of exposure based on prescription registries tended to overestimate exposure, particularly early in pregnancy. This would have the effect of underestimating risk in all categories, but particularly early in pregnancy, leaving open the possibility that early exposure might also increase risk significantly.
The authors noted that one of the studies included in the meta-analysis had found a slight increased risk of PPHN associated with a history of admission to hospital for a psychiatric condition (30% increased risk), but the risk for women with this history who used SSRIs in late pregnancy was over three times that of women who did not use the drugs. Results of another study included in the meta-analysis suggested that there was no independent association between maternal depression and PPHN. Risk in the Canadian study appears to increase with increased exposure, another sign that the drug itself, not depression, is causing PPHN.
The authors explained that the blood vessels in the lungs of infants with PPHN do not relax after birth, leading to poor oxygenation. “Symptoms can range in severity from mild respiratory distress to the most severe form, with hypoxia necessitating intensive medical care.” The condition is typically estimated to be fatal in 10-20% of cases, though a 2011 study in the journal Pulmonary Medicine reported a mortality rate over 30%.
Even among survivors there are long-term consequences. A September 2, 2013 review article in the journal Frontiers in Pediatrics stated that neurodevelopmental disabilities including cognitive delays and hearing deficit can be seen in 6.4% of PPHN survivors. A long-term follow-up study also found that children treated for PPHN “are at high risk for sensorineural hearing loss” and added, “The incidence of chronic health problems and use of remedial education was high.”
New Effexor Study Finds Significant Link to Serious Birth Defects
Date: December 26, 2012
Publication: Birth Defects Research, Part A: Clinical and Molecular Teratology
Drugs: Effexor – venlafaxine
An epidemiological study of birth defects in the United States has added new evidence to a growing body of data linking antidepressant usage during pregnancy to miscarriage and birth defects, including serious congenital heart defects.
The study was published online on December 26, 2012 in the journal Birth Defects Research, Part A: Clinical and Molecular Teratology. It specifically focused on the effects of the SNRI (serotonin-norepinephrine reuptake inhibitor) antidepressant venlafaxine (Effexor), approved by the U.S. Food and Drug Administration (FDA) to treat depression and anxiety in adults.
Using data from the National Birth Defects Prevention Study, researchers looked at over 19,000 women whose pregnancies (delivery dates between 1997 and 2007) had been affected by one of 30 different birth defects. Another 8,002 women with normal births served as controls.
The researchers found “statistically significant associations” between exposure to venlafaxine and the following defects:
- Anencephaly – a fatal neural tube defect characterized by an absence of a large part of the brain and skull. It occurs during early development, when the neural tube of an unborn baby fails to close. Babies born with anencephaly usually die within days after their birth.
- Atrial septal defects (ASD) – described as a hole in the heart, ASD is a congenital heart defect that allows blood to flow between two chambers of the heart that are normally separated – the left and right atria. The wall of the heart, called the septum, usually separates the atria. In babies with ASD, oxygen –rich blood in one side of the heart directly mixes with the oxygen-poor blood of the other, leading to poor oxygen levels in the blood.
- Coarctation of the aorta – a narrowing of the aorta, the large blood vessel that distributes oxygenated blood from the heart to all parts of the body. The narrowing, or coarctation, of the aorta makes it difficult for blood to flow through the artery, resulting in symptoms like chest pain, failure to thrive, poor growth and shortness of breath. Most infants with coarctation of the aorta will need surgery to treat the condition.
- Cleft palate – a craniofacial defect characterized by an opening in the roof of the mouth which can range from a small notch to a split that runs along the entire length of the palate. Children with cleft palates may appear deformed, have problems with feeding and speech and may be at risk of developing ear infections. Treatment for cleft palate usually involves surgery within the first year of life.
- Gastroschisis – a birth defect in which the baby’s intestines stick out of the body through a hole in the abdominal wall. An infant both with gastroschisis will have unprotected intestines exposed to amniotic fluid in the womb. Babies born with this birth defect will need surgery, and prognosis depends on the size of the abdominal cavity and severity of the birth defect.
In this study exposure to venlafaxine was defined to be any reported use of the drug from one month preconception through the third month of pregnancy. To assess only the effects of venlafaxine, women who reported using other antidepressants were excluded from the study. To control for the possibility that some mothers who reported no exposure had in fact taken the drug, the authors reassessed their data assuming that the actual number of control mothers who had taken venlafaxine was 30% higher than the number who reported exposure. Their reassessment nevertheless found “all associations remained elevated.”
Discussing the implications of their results, the researchers noted that the two neurotransmitters most affected by venlafaxine, serotonin and norepinephrine, have been shown to play an important role in the development of the embryo into a fetus. They wrote, “Thus, if venlafaxine is taken during early pregnancy and interferes with these embryologic signaling pathways, it is plausible that venlafaxine could affect craniofacial and cardiac development. This is consistent with our findings of associations with septal heart defects, LVOTO defects [left ventricular outflow tract obstruction. Coarctation of the aorta is one example of this defect.], and cleft palate.”
The authors concluded, “Our data suggest associations between periconceptional [occurring around the time of conception] use of venlafaxine and some birth defects” and called for additional studies to confirm their results.
Effexor and Pristiq Linked to Increased Risk of Violence
Date: December 15, 2010
Publication: Public Library of Science
Drugs: Celexa – citalopram, Effexor – venlafaxine, Lexapro – escitalopram, Prozac – fluoxetine
According to an Institute for Safe Medication Practices study published in the journal PloS One and based on data from the FDA’s Adverse Event Reporting System, Venlafaxine (Effexor) is 8.3 times more likely than other drugs to be related to violent behavior. Effexor has been identified as one of 31 drugs that are disproportionately linked with reports of violent behavior towards others. The antidepressant Desvenlafaxine (Pristiq), is 7.9 times more likely to be associated with violence than other drugs according to the same study.
- Top Ten Legal Drugs Linked to Violence – Time.com
- Prescription Drugs Associated with Reports of Violence Towards Others – Public Library of Science
Effexor (Venlafaxine) Doubles Risk of Miscarriage in Pregnant Women
Date: May 31, 2010
Publication: Canadian Medical Association Journal
Drugs: Effexor – venlafaxine
Adding to the growing list of worries associated with antidepressants, a new study has found that the risk of miscarriage is significantly higher in women who take SSRI (selective serotonin reuptake inhibitor) and SNRI (serotonin-nonrepinephrine reuptake inhibitor) antidepressants, such as Effexor, early in their pregnancies.
According to a May 31, 2010 study published online in the Canadian Medical Association Journal by scientists at the University of Montreal, women who take antidepressants like Effexor, Lexapro, Celexa, Prozac and Zoloft during the first trimester of their pregnancy were significantly more likely to miscarry than women who did not take antidepressants. Researchers found that the risk associated with miscarriage was 68 percent higher in women who used the drugs. The researchers also found that Effexor was among the antidepressants which carried the highest risk.
Researchers took data from the Quebec Pregnancy Registry. They studied pregnancies since 1997 and compared women who miscarried in their 20th week with women who did not lose their babies early in the pregnancy. The results showed that the risk of miscarriage nearly doubled with the use of venlaxafine (Effexor). The data has led researchers to warn that the use of antidepressants, especially venlaxafine, should be used with extreme caution during pregnancy.
The miscarriages may be related to malformations of essential organs. Baum Hedlund represents many families whose children were born with birth defects to mother’s who took Effexor, venlafaxine or Pristiq during their pregnancies. Their clients’ birth defects range from heart defects, lung defects, craniosynostosis (abnormally shaped skull), infant omphalocele (abdominal wall defects), club foot, and cleft lip and cleft palate.
Baum Heldund has represented more clients in antidepressant injury cases than any other law firm in the United States: “Women who take antidepressants like Effexor while pregnant are unknowingly putting their unborn babies at risk. Instead of experiencing the normal joys of child rearing, our clients are trying to save their babies lives.” Venlafaxine has also been shown to increase the risk of developmental delays in babies.
Antidepressants such as Effexor and Pristiq may cause birth defects in newborns. According to information which has been emerging since 2005, data from various international studies show that some antidepressants may cause birth defects. The FDA has issued warnings about SSRI antidepressants since 2005, and their capability of causing birth defects.
Taking Antidepressants, Including Effexor, During Pregnancy May Delay Developmental Milestones
Date: March 2010
Drugs: Celexa – citalopram, Effexor – venlafaxine, Zoloft – sertraline
The study, published in the March 2010 issue of Pediatrics, found associations between exposure to antidepressants in late pregnancy and prolonged motor developmental milestones at six and 19 months of age. Effexor was one of the antidepressants that was listed in the study.
The participants of the study were obtained from the Danish National Birth Cohort. Out of 904 pregnant women who reported depression, 415 used antidepressant medication, including the antidepressant Effexor, and 489 did not. Researchers then compared certain developmental milestones between the children of those women who took the drugs during pregnancy, and those who did not.
According to researchers, children exposed to antidepressants in the womb took 16 days longer to sit without support and nearly a month longer to walk compared to children who were not prenatally exposed to the medication. Although the delay is still within the range of normal development, researchers noted that the data “may suggest that human fetal brain development is susceptible to antidepressant exposure.” Results also show that boys, in particular, are susceptible to this risk.
Researchers also found that fewer children exposed to the antidepressants were able to occupy themselves for 15 minutes at 19 months of age than those whose mothers did not take the drug.
The researchers concluded that “The results of our study suggest an effect of antidepressants exposure on fetal brain development” and added that longer follow-up monitoring of the children is necessary in order to further understand the clinical and public health implications of the results.