Antidepressants and uterine contractility: an in vitro investigation on the effects of sertraline and escitalopram on rat myometrium

During pregnancy and shortly after delivering a baby, many women (about 10%) experience depression as a result of biological, hormonal and psychosocial changes. Moreover, some women on antidepressant treatment may become pregnant. As the depression symptoms seriously interfere with daily life and untreated depression can have harmful effects on both the mother and the baby, therapy including use of medication may be required. So, deciding to start or continue to antidepressants during pregnancy is continous to be a difficult topic.Studies have reported an increased likelihood of miscarriage, preterm delivery and postpartum uterine bleeding in mothers taking medication to treat depression during pregnancy, but it is not known whether these side effects occur systemically or as a result of a direct effect on the myometrium muscle. In this thesis, the effects of sertraline and escitalopram on spontaneous and oxytocin-induced contractions in myometrial tissue samples isolated from adult rats were investigated. Myometrial strips obtained from Sprague-Dawley rats were suspended in an organ bath and isometric contractions were recorded. Spontaneous contractions after adaptation to the hanging tension applied in the organ bath were evaluated and contractions were stimulated with oxytocin for some protocols. The effects of cumulative concentrations of sertraline and escitalopram on the amplitude, frequency and area under the contraction curve values of contractions were evaluated by 10-minute periods. Sertraline significantly decreased the AUC (area under the contraction curve) and frequency values in oxytocin-induced contractions in non-pregnant rats at a concentration of 10x10-6 (p<0.05). Sertraline significantly decreased the AUC values in oxytocin-induced contractions in pregnant rats at a concentration of 10x10-6 (p<0.05). In addition, sertraline decreased the AUC values in spontaneous contractions in pregnant rats at 3x10-6 and 10x10-6 concentration (p<0.05). Escitalopram significantly decreased AUC values in spontaneous contractions in non-pregnant rats at a dose of 10x10-6 (p<0.05). The minimal inhibitory effect of sertraline and escitalopram on contractions of rat myometrium is dose dependent as mentioned above, and the doses at which this inhibitory effect occurs are above clinically relevant doses. However, further studies are needed to support these effects in the in vitro animal model with human studies.