Lymphocyte beta 2-adrenoceptor density during menstrual cycle and pregnancy, in delivery and puerperium

Lymphocyte beta 2-adrenoceptor density was determined in 11 women during the normal menstrual cycle and 15 women during normal pregnancy. No significant difference in lymphocyte beta 2-adrenoceptor density was established in this follow-up study during the menstrual cycle or pregnancy. Lower lymphocyte beta 2-adrenoceptor density was established just after delivery and in puerperium compared with that during pregnancy. It is likely that the high catecholamine concentration during parturition together with the duration of labour and delivery caused down-regulation of the beta 2-adrenoceptors. In puerperium the irregular day-rhythm and the stress of caring for the newborn may also have an effect.