Antidepressants during pregnancy cause lung and intestinal problems in babies

Children whose mothers took antidepressants during pregnancy should be monitored more closely by health professionals. Such children experience sleep and feeding problems in their first few days of life, but can also have intestinal and lung problems into their second year. These are the findings of hospital pharmacist Peter Ter Horst, who will be awarded his PhD at the University of Groningen on 11 January.

About two percent of all pregnant women in the Netherlands take antidepressants. Although these medicines can have serious effects on the unborn child, few studies have been done on the subject.

Clomipramine

Hospital pharmacist Ter Horst conducted research into the antidepressant clomipramine, a frequently prescribed drug at the Isala Clinics where Ter Horst works. Little was known about this drug in the literature. He set up a control programme involving ten pregnant women which monitored mother and child during pregnancy and after birth.

Withdrawal symptoms

Many children had withdrawal symptoms 24 hours after birth. These were usually fairly harmless, such as sleep and feeding problems, but they also included arrhythmia, breathing problems and epileptic fits.

No link was found between these symptoms and the concentration of the antidepressant in the baby’s blood. Ter Horst said: ‘This makes withdrawal symptoms difficult to predict. It is therefore important to monitor the children for longer than 48 hours, also because it takes several weeks for clomipramine to break down completely.’

Laxatives and respiratory medication

Ter Horst also discovered that children of mothers who used antidepressants during pregnancy needed 20-40% more laxatives in the first two years after birth. This shows that the antidepressants affect the development of the gastrointestinal tract. This hypothesis had been put forward in published studies involving laboratory animals, but had never been demonstrated for humans.

Young children also use more respiratory medication. ‘We see a marked increase compared with children who are not exposed to antidepressants, especially if the mother took antidepressants in the first trimester of pregnancy, the period in which the organs are formed. We think that the medication has an effect on lung development.’

Patient compliance a concern

Ter Horst discovered from pharmacy records that pregnant women don’t take their antidepressants as prescribed and have pills left over at the end of the month. This situation is worrying because the mother then continues to suffer from her depression while the child is exposed to the drug.

‘Pregnant women believe that the drug is a toxin and they worry about the health of their child. But depression is also harmful to the unborn child. If the medication is really necessary, women do need to take it properly.’

Interdisciplinary consultation

Ter Horst therefore advises health professionals, such as pharmacists, GPs and gynaecologists to discuss the problems with one another. ‘An extra ultrasound for example can rule out problems with organ growth and can reassure the mother. Interdisciplinary consultation is a good way to improve care.’

Switching to other drugs in time

Ter Horst thinks that health professionals should also be more alert before the pregnancy. For example, the antidepressant seroxat (paroxetine) is known to cause high pulmonary blood pressure and heart valve abnormalities in the foetus. Doctors should advise women wishing to have a child to switch to another, safer drug before they become pregnant. ‘Changing from one drug to another takes time as the old drug has to be reduced slowly and the new one might not work. GPs and pharmacists should point this out to their patients wishing to become pregnant and should supervise the switch.’

Curriculum vitae

Peter ter Horst (Almelo, 1972) studied pharmacy at Utrecht University. He is a hospital pharmacist at the Isala Clinics in Zwolle, where he conducted his PhD research. Ter Horst will be awarded his PhD on 11 January 2013 at the Faculty of Mathematics and Natural Sciences at the University of Groningen for his dissertation entitled Clinical Pharmacology of antidepressants during pregnancy. The PhD supervisors are Bob Wilffert and Lolkje de Jong-van den Berg.

Note to editor

Contact: Peter ter Horst tel. 0384247244, e-mail: p.g.j.ter.horst@isala.nl