EPISODIC SECRETION OF ACTIVIN-A IN PREGNANT-WOMEN

The aim of the present study was to determine the characteristics of a ctivin A secretion in women with normal and abnormal pregnancy. With t his purpose, a prospective study was done to evaluate the putative pul satile pattern of serum activin A in serial specimens of blood collect ed during a certain amount of time (every 15 min for 3 h). A group of pregnant women (N=24) participated in a cross-sectional study. They we re subdivided into three groups: healthy pregnant women (N=8), patient s with preterm labor (N=8) and patients with gestational diabetes (N=8 ) before and after insulin therapy. Secretory pulses of serum activin A were determined in all patients with a specific frequency and amplit ude by using two different computerized analyses, i.e. DETECT and CLUS TER, Mean+/-SEM values of serum activin A were significantly higher in patients with preterm labor and gestational diabetes than in controls (p <0.01), showing a significant decrease following insulin therapy i n diabetic patients (p <0.01). Specific pulses of serum activin A leve ls were observed in all women, The mean pulse frequency did not change significantly between healthy controls and the different pathological groups, Patients with gestational diabetes after insulin therapy show ed a pulse frequency that was significantly higher than in controls (p <0.05). When the mean peak amplitude of activin A pulses was evaluate d, patients with preterm labor or gestational diabetes showed values t hat were significantly higher than in healthy pregnant women (p <0.01) . A significant, inverse correlation between pulse frequency and ampli tude was found both in healthy pregnant women (p <0.05) and in patient s with gestational diabetes (p <0.001). The present study showed that circulating activin A levels in pregnant women change in a pulsatile p attern whose pulse amplitude is modified in the presence of gestationa l diseases, such as preterm labor or gestational diabetes.