Sertraline concentrations in pregnant women are steady and the drug transfer to their infants is low

Eur J Clin Pharmacol. 2021 Sep;77(9):1323-1331. doi: 10.1007/s00228-021-03122-z. Epub 2021 Mar 22.


Purpose: Sertraline, a selective serotonin reuptake inhibitor (SSRI), is one of the most commonly used antidepressant during pregnancy. Plasma sertraline concentrations vary markedly between individuals, partly explained by variability in hepatic drug metabolizing cytochrome P450-enzyme activity. Our purpose was to study the variability in the plasma concentrations in pregnant women and the passage to their infants.

Method: Pregnant women with moderate untreated depression were recruited in 2016-2019 in Stockholm Region and randomized to treatment with sertraline or placebo. All received Internet-based cognitive behavior therapy as non-medical treatment. Sertraline plasma concentrations were measured around pregnancy weeks 21 and 30, at delivery, 1-month postpartum, in cord blood and at 48 h of age in the infant. The clinical course of the infants was followed.

Results: Nine mothers and 7 infants were included in the analysis. Median dose-adjusted sertraline concentration in second trimester was 0.15(ng/mL) /(mg/day), in third trimester and at delivery 0.19 and 1-month postpartum 0.25, with a 67% relative difference between second trimester and postpartum. The interindividual variation was 10-fold. Median concentrations in the infants were 33% and 25% of their mothers', measured in cord blood, and infant plasma, respectively. Only mild and transient adverse effects were seen on the infants.

Conclusion: Placental passage of sertraline to the infant is low. However, the interindividual variation in maternal concentrations during pregnancy is huge, why therapeutic drug monitoring might assist in finding the poor metabolizers at risk for adversity and increase the safety of the treatment.

Trial registration: The trial was registered at July 9, 2014 with TRN: NCT02185547.

Keywords: Antenatal depression; Infant; Pharmacokinetics; Pregnancy; Selective serotonin reuptake inhibitors; Therapeutic drug monitoring.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Antidepressive Agents / blood
  • Antidepressive Agents / pharmacokinetics*
  • Antidepressive Agents / therapeutic use
  • Cognitive Behavioral Therapy / methods
  • Depressive Disorder / drug therapy
  • Double-Blind Method
  • Female
  • Fetal Blood / chemistry
  • Humans
  • Infant, Newborn
  • Male
  • Milk, Human / chemistry
  • Placenta / chemistry
  • Postpartum Period
  • Pregnancy
  • Pregnancy Trimesters
  • Prenatal Exposure Delayed Effects / blood*
  • Sertraline / blood
  • Sertraline / pharmacokinetics*
  • Sertraline / therapeutic use


  • Antidepressive Agents
  • Sertraline

Associated data