The aim of this study was to investigate the possible mechanism of the regulation of plasma adenosine concentration [ADO] in normal pregnancy. We measured the activities of circulating enzymes that are involved in the production and metabolism of adenosine, and plasma [ADO] in nonpregnant (n = 14) and normal pregnant women (n = 14) in the third trimester. In pregnant women, the activity of plasma 5′-nucleotidase and plasma [ADO] were significantly elevated and plasma adenosine deaminase activity was significantly reduced. Enzymatic activities of both plasma enzymes appear to be changed in a way that would favor increased adenosine concentrations.

The percentages of Th1 and Th2 cells and the Th1:Th2 ratios in peripheral blood from 22 patients with a singleton pregnancy at 30 and 36 weeks' gestation, on admission for the spontaneous onset of labor pains, at 1 minute after placental delivery and on day 7 after delivery were determined using flow cytometry. The percentages of Th1 and Th2 cells and the ratio of Th1:Th2 did not markedly change during 30 weeks' gestation and 1 minutes after placental delivery. However, the percentage of Th2 cells had decreased significantly at 7 days after delivery. In addition, the Th1:Th2 cell ratios were significantly elevated on day 7 after delivery. Thus, the termination of pregnancy may not be associated with a change in maternal Th1:Th2-immunity.

The aim of this study was to investigate the relationship between plasma endothelin 1 (ET-1) levels and T helper (Th)-1:Th2 cell immunity in women with preeclampsia. The percentage of Th1 and Th2 cells and the Th1:Th2 cell ratios in peripheral blood from 11 normal pregnant women and 11 patients with preeclampsia at 29–34 weeks of gestation were calculated using flow cytometry. The plasma ET-1 level was also determined using a modified radioimmunoassay. The plasma ET-1 concentrations and the Th1:Th2 cell ratios in normal pregnancies were significantly lower than those in patients with preeclampsia. Negative correlations were found between plasma ET-1 levels and Th2 cells in both the preeclamptic pregnancy groups and in the normal pregnant women. Our results indicate that elevated ET-1 levels are associated with a Th1:Th2 imbalance in preeclampsia.

The percentage of T-helper (Th)1, Th2 cells and the Th1:Th2 cell ratios in peripheral blood from 14 normal nonpregnant women, 23 normal pregnant women and 9 patients with twin pregnancies without preeclampsia at 28–32 weeks’ gestation were calculated using flow cytometry. In normal pregnant women, the percentage of Th1 cells and Th1:Th2 ratios were significantly lower than those in nonpregnant women. In twin pregnancies, the percentage of Th1 cells and the Th1:Th2 ratios were significantly lower than those in nonpregnancies. In twin pregnancies; in addition, the percentage of Th1 cells was significantly lower than that in singleton pregnancies. Our findings show a markedly predominant Th2 immunity in twin pregnancies.

We present here a case of maternal reaction to fetomaternal transfusion complicated by subchorionic hemorrhage. A 40-year-old woman, gravida 2, para 0, was admitted to our hospital at 25 weeks' gestation because of high blood pressure. On the morning of 32 weeks and 2 days' gestation, she developed sudden onset nausea, dyspnea and regular uterine contractions. Blood pressure was 80/50 mmHg and pulse was 110 beats/minute. At this time, her WBC, hemoglobin and platelets were decreased significantly. Two hours after onset, the patient's condition improved spontaneously. Increased serum alpha-fetoprotein level (3.0 multiple of median) was observed. She was suggested to be a case of acute fetomaternal transfusion.