Prevalence of Antidepressant Use during Pregnancy in Denmark, a Nation-Wide Cohort Study

AIM: The aim of this study was to assess the prevalence and patterns of exposure to antidepressants before, during and after pregnancy in a cohort including all pregnant women in Denmark between 1997 and 2010. METHODS: We performed a retrospective cohort study including 912 322 pregnancies. Information was retrieved from the Danish Birth Registry and The Register of Medicinal Product Statistics to identify women redeeming an antidepressant prescription during pregnancy. Exposure periods were based on standard treatment doses and dispensed pack sizes. RESULTS: We identified 19 740 pregnancies exposed to an antidepressant at some point during pregnancy. The rate of exposure increased from 0.2% in 1997 to 3.2% in 2010. We found that the rate of exposure was halved during the first 3 months of pregnancy. In contrast, we describe a clear increase in exposure after pregnancy among pre-delivery treatment-naïve women. CONCLUSIONS: In spite of uncertainty concerning antidepressants’ safety during pregnancy we find a 16-fold increase in exposure rates between 1997 and 2010. The rates describe a sharp decrease in exposure during pregnancy that is probably caused by physicians’ hesitation to prescribe antidepressants and women’s fear of unwanted effects on the unborn child. More studies are needed to clarify the consequences of antidepressant discontinuation during pregnancy

Clarithromycin in early pregnancy and the risk of miscarriage and malformation: a register based nationwide cohort study.

BACKGROUND: The antibiotic clarithromycin has been associated with fetal loss in animals and a study has found a doubling in the frequency of miscarriages among women using clarithromycin in pregnancy. The aim of the study was to investigate whether clarithromycin use in early pregnancy was associated with an increased risk for miscarriages and major malformations. METHODS: We conducted a nationwide cohort study including all women in Denmark with a known conception between 1997 and 2007. The Fertility Database was used to identify all women giving birth and the National Hospital Register was used to identify all women with a record of miscarriage or induced abortion. Prescription data was obtained from the National Prescription Register. The primary outcome was the number of miscarriages and offspring with major congenital malformations among users of clarithromycin compared to non-users. RESULTS: We identified 931 504 pregnancies (705 837 live births, 77 553 miscarriages, and 148 114 induced abortions). 401 women redeemed a prescription of clarithromycin in the first trimester of which 40 (10.0%) experienced a miscarriage and among the live born nine (3.6%) had offspring with malformations. The hazard ratio (HR) of having a miscarriage after exposure to clarithromycin was 1.56 (CI95% 1.14-2.13). There was no increased hazard of having a miscarriage when being exposed to penicillin or erythromycin. There was no increased prevalence (OR = 1.03 (CI95% 0.52-2.00)) of having offspring with malformations after exposure to clarithromycin. CONCLUSIONS: We found an increased hazard of miscarriage but no increased prevalance of having offspring with malformations among women redeeming a prescription of clarithromycin in early pregnancy. This is supported by previous studies in animals and humans. However, further research is required to explore the possible effect of treatment indication on the associations found

Antidepressants included in the study.

<p>Table shows the generic names and their corresponding ATC codes for antidepressants included in the present study. SSRI: Selective Serotonine Reuptake Inhibitor; TCA: Tri Cyclic Antidepressant (Non-selective Monoamine Reuptake Inhibitor).</p

Basic characteristics for women exposed to an antidepressant during pregnancy.

<p>Table shows the number (n) of pregnant women within each subcategory. Some women were exposed to several antidepressants during pregnancy. Number in parenthesis denotes percentage of pregnant women within each exposure. Information on BMI was only available for women giving birth after 1 January 2004. Chi-square tests were used to assess the overall p value for the group comparison between unexposed and women exposed to “any AD”.BMI, body mass index; SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressants; AD, antidepressant.</p

Pre-pregnancy treatment-naïve women exposed to an antidepressant.

<p>Number of pre-pregnancy treatment-naive women exposed to an antidepressant during and after pregnancy. Number in parenthesis is the percentage of ‘any antidepressant’. Sum of percentages adds up to more than 100% due to some pregnancies being exposed to more than one antidepressant in the given period. SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressants; AD, antidepressant.</p

Number of women exposed to an antidepressant during pregnancy.

<p>Number in parenthesis is the percentage of ‘any antidepressant’. Sum of percentages adds up to more than 100% due to some pregnancies being exposed to more than one antidepressant in the given period. SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressants; AD, antidepressant.</p

Percentage of pregnant women in treatment with an antidepressant for each day from 180 days before conception to 630 days after conception (approximately 1 year after mean time of delivery).

<p>The figure is divided into three areas of different color indicating the period of treatment start; before (dark blue), during (blue) or after pregnancy (light blue).</p