Binding of tritiated yohimbine to platelets in women with maternity blues.

Platelet alpha 2-adrenoceptor binding was measured in 108 women in the 36th week of pregnancy, at ten and twenty days and at three and six months post-partum. An age matched non-pregnant control group of women (N = 25) was also studied. The number (Bmax) of alpha 2-adrenoceptors was elevated antepartum but fell to control values on the tenth post-partum day. At three and six months post-partum, however, alpha 2-adrenoceptor Bmax was again increased. Women who developed maternity blues (N = 59) had significantly more platelet alpha 2-adrenoceptors than those who did not (N = 49) at both ten and twenty days post-partum. In addition their alpha 2-adrenoceptor Bmax was greater than controls at all time points measured except the tenth post-partum day. In contrast, the alpha 2-adrenoceptor Bmax of women without the blues did not differ from controls at any stage. It is suggested that women who develop maternity blues may have a relatively enduring abnormality in alpha 2-adrenoceptor sensitivity which is associated with psychological symptoms when concentrations of circulating sex-steroids suddenly change.