Beta-adrenoceptors in obstetrics and gynecology.

One hundred and twenty years after the description of extracts from the adrenal medulla, the use of beta-blockers and beta-agonists evolved from antianginal drugs and tocolytics to ligand-directed signaling. Beta-blockers in the fields of obstetrics and gynecology have so far been limited to the consideration of continuing treatment of disorders of the cardiovascular system and other dysfunctions that started before pregnancy. Studies in recent years have shown that beta-adrenoceptor signaling might be crucial in carcinogenesis and metastasis, apoptosis and anoikis. On the other hand, the use of beta-adrenoceptor agonists in tocolysis is, as yet, the primary method for inhibiting premature uterine contractions. Unfortunately, the efficacy of current pharmacological treatment for the management of preterm labor is regularly questioned. Moreover, studies related to non-pregnant myometrium performed to date indicate that the rhythmic contractions of the uterus are required for menstruation and have an important role in human reproduction. In turn, abnormal uterine contractility has been linked to dysmenorrhea, a condition associated with painful uterine cramping. The benefits of the use of beta2-adrenoceptor agonists in dysmenorrhea are still unclear and should be balanced against a wide range of adverse effects recognized with this class of medication. The ideal tocolytic agent is one which is effective for the pregnant or non-pregnant woman but has no side effects on either the woman or the baby. Looking to the future with both caution and hope, the potential metamorphosis of beta3-adrenoceptor agonists from experimental tools into therapeutic drugs for tocolysis warrants attention.