Interview has been edited for clarity.
Dr. Abel says that taking antidepressants during pregnancy is safe, and it may actually be safer to take an antidepressant than to not for people who are very depressed, actively suicidal, or who have a history of recurrent depression: “It may be safer to continue to take antidepressants than to stop because it may prevent relapsing into a further depressive episode.”
She mentions that it’s important to remember that many of the people who’ve been diagnosed with depression have a mild form of depression. And mild forms of depression often get better without medical intervention or drugs. Help and support from other people or maybe talk therapy can be effective without the need for medication, according to Dr. Abel.
She says that intensive forms of psychological support, like cognitive behavioral therapy (CBT), are usually only needed for more severe depression. Mild depression often resolves on its own with time.
“Among people who stay severely depressed, about five percent of them continue to take antidepressants during pregnancy,” says Dr. Abel. “That’s an average figure; but in pregnant people on antidepressants, it was about two or three percent 20 years ago, and it’s 10 percent today. What this means is that over the past 25 years in the UK, more depression is being reported, and more antidepressants are being prescribed.”
“That’s important because, of course, in 1992 we didn’t have selective serotonin reuptake inhibitors (SSRIs), and people were very concerned about treating pregnant people with tricyclics — the old antidepressants. Today, most people take SSRIs.”
If we look at what happens in the first year after delivery, there are about twice as many people taking antidepressants postpartum as people taking them during pregnancy, according to Dr. Abel.
“This information comes from primary care, from GPs,” she says. “That’s important because, if we look at Swedish data, which only includes secondary care and probably people with more serious illness, the rates are much lower.”
Dr. Abel says that the number of women in Sweden with more severe depression during pregnancy or after delivery is much lower, as is the number of them taking antidepressants.
“This suggests that probably between 70 to 80 percent of the women with depression in the UK primary care setting have a much less severe depression, and maybe quite a lot of them could and should be treated without medication because they have a milder form of illness.”
Whether antidepressants are safe for the fetus is a complicated issue.
“It’s complicated because the information we have about possible effects of antidepressants on the fetus doesn’t exist in a vacuum.”
In other words, the more severe a depressive illness, the more likely the pregnant person will be given an antidepressant. But they will also be more likely to smoke, eat poorly, miss prenatal appointments, or be unsupported.
The behaviors that are common for depressed people during pregnancy — not the antidepressants themselves, not even the depression — are more likely to cause problems for the baby.
So, according to Dr. Abel, independent of whether a pregnant person is taking medicine or not, the fetus is exposed to many other factors that can influence its development and chances of doing well. The behaviors that are common for depressed people — not the antidepressants themselves, not even the depression — are more likely to cause problems.
“We see that mothers who are depressed enough to be in secondary care, whether they take antidepressants or not, are more likely to have premature babies, slightly smaller babies, or babies with a little more difficulty at birth,” says Dr. Abel.
“There is also evidence of a relationship between depression in pregnancy and risk of autism in children, particularly autism without intellectual disability. There are more girls, maybe, in that group than boys. Autism with intellectual disability is more likely in boys.”
Dr. Abel says that this is unlikely to be solely related to SSRIs, because before SSRIs, there was also a risk of autism in the offspring of parents who have depression.
And there’s a final layer of complication to the topic of depression in pregnancy, antidepressants in pregnancy, and the risks for infants.
This is what Dr. Abel says: “First, we know that SSRIs are not just given for depression. They’re increasingly prescribed for a range of problems, including obsessive–compulsive disorder (OCD), anxiety, panic, poor sleep, psychosis, schizophrenia, and bipolar disorder — many different things are treated with SSRIs.
“Secondly, compared to people who are pregnant at the same time but don’t have mental illness, or to people with any mental illness during pregnancy, depressed pregnant people appear to be much more likely to receive many other medicines that aren’t antidepressants.
“For instance, they are nearly three times more likely to receive antibiotics during pregnancy. A person taking antibiotics during pregnancy usually means that they’ve had an infection, and the commonest cause of prematurity and poor fetal growth (small babies) is infections in pregnancy.
“We can see how complicated this question becomes when we say that taking antidepressants is associated with having small, premature infants,” says Dr. Abel. “This may have nothing to do with antidepressants or with depression.”
“When talking about a link between antidepressants and infant/fetal congenital malformations, the story may be a little more straightforward,” says Dr. Abel. “WHO reports that about three percent of all pregnancies develop congenital malformations. Most malformations are minor and treatable, such as cleft palate or finger anomalies, rather than major heart defects. The rate is about three to four in 100 births, so it’s low in the general population.”
Dr. Abel says that some of the risk factors associated with depression or other mental illnesses are the same as those for congenital malformations. So being young, a teenager, or living in poverty are all factors. “But when you look at the rates in people who are depressed in pregnancy and taking antidepressants, about one more child in a hundred is developing congenital malformations. And again, most of those are likely to be minor — not major heart defects.”
So in general, if someone needs to take antidepressants during pregnancy, the sense is that these medicines are safe for infants, according to Dr. Abel.
She says that some medicines clearly have been linked to problems, however. Paroxetine has been associated with specific congenital heart defects and pulmonary hypertension (high blood pressure in the baby’s lungs).
Other antidepressants have been linked with bleeding disorders in pregnancy and poor fetal growth. And many infants may show temporary irritability after birth, which is thought to be a type of SSRI-withdrawal syndrome because at birth the baby no longer receives any SSRIs — but this doesn’t usually require treatment.
Want to know more? Don’t miss this interview: Kathryn Abel answers the five top questions about antidepressants and pregnancy.