Maternal plasma and amniotic fluid levels of estradiol, estrone, progesterone, and prolactin in early pregnancy

During the 16th to 20th weeks of gestation, maternal plasma (mean) level of estradiol is 5.2 ng/mL; estrone, 3.0 ng/mL; estriol, 2.1 ng/mL; progesterone, 4235 ng/dL; and prolactin, 74 ng/mL. Amniotic fluid levels are: estradiol, 446.8 pg/mL; estrone, 234.1 pg/mL; progesterone, 5200 ng/dL; and prolactin, 2633.5 ng/mL. Maternal prolactin concentrations correlate with plasma estradiol. Amniotic fluid prolactin levels correlate significantly with maternal plasma concentrations of estradiol and estrone. The mechanisms for the possible relationship between maternal estradiol and pituitary and decidual tissue production of prolactin are discussed.     

Maternal serum levels of estriol, prolactin, human placental lactogen and chorionic gonadotrophin related to fetal sex in normal and abnormal pregnancies

A total of 222 pregnant women had repeated hormone assays of prolactin, estriol, human chorionic gonadotrophin and placental lactogen between week 20 and delivery. The aim of this study was to investigate whether maternal serum levels of the above-mentioned hormones differed between normal and abnormal pregnancies, that is preterm, preterm small-for-date (SFD), SFD at-term and normal at-term deliveries, with special regard to fetal sex. The results of the present study indicated differences related to preterm deliveries and intrauterine growth retardation. This finding was reflected in the estriol levels when mothers of both boys and girls were included, suggesting a primary involvement of fetoplacental factors in these pathological pregnancies. However, when only mothers of girls were investigated, the development of growth retardation was mainly seen in maternal serum hPL differences, thus suggesting a placental involvement.     

Predictive value of human placental lactogen determinations in pregnancy.

The relation of human placental lactogen (hPL) levels to pregnancy outcome was studied in normal and preeclamptic pregnancies, hPL determinations were performed between 38 and 44 weeks of gestation, and the results were compared with birthweight and Apgar scores in three groups. The results of hPL determinations permitted prediction of intrauterine growth retardation in all except 2 patients. The value of hPL measurement as a screening test in pregnancy is noted.     

Toxemia of pregnancy: assessment of fetal distress by urinary estriol and circulating human placental lactogen and alpha-fetoprotein levels.

The efficacy of three biochemical methods for the detection of fetal distress was assessed in a prospective study of 224 singleton pregnancies complicated by toxemia. Fetal distress was diagnosed in 65 cases (29 per cent). Abnormally low urinary estriol (E3) excretion pointed out 63 per cent, low serum levels of human placental lactogen (HPL) 27 per cent, and elevated maternal serum alpha fetoprotein (AFP) 10 per cent of distressed fetuses. The efficacy of each test increased with the severity of maternal disease. The frequencies of false pathologic levels were: E3 19 per cent, HPL 0 per cent, and AFP 1 per cent of the cases with a normal fetal outcome. Although E3 was by far the most effective marker, abnormal levels of HPL and AFP provided supportive evidence for fetal distress by pointing out those cases in which E3 reading was not a false positive.     

Absence of human placental lactogen in an otherwise uneventful pregnancy.

Human placental lactogen (hPL) is commonly used in surveying the placental function during normal and pathologic pregnancies. This report describes a pregnancy where hPL could not be found in maternal serum or placental tissue. The pregnancy was in all other respects completely normal, ending with the birth of a normal baby. Some possible reasons and consequences of this unique event are discussed.     

A pregnancy without detectable human placental lactogen (hPL)

During a pregnancy of a 35 year old woman, we could not detect HPL in the peripheral serum, whereas other hormones showed normal values. Fetal growth ceased in the 36th week and a live neonate was delivered by caesarean section. The histological findings of the placenta and the perinatal record were not so unusual that they could account for the absence of HPL. This case illustrates that fetal growth is possible without HPL-production.     

Prediction of fetal outcome by urinary estriol, maternal serum placental lactogen, and alpha-fetoprotein in diabetes and hepatosis of pregnancy.

Urinary estriol, serum placental lactogen (hPL), and alphafetoprotein (AFP) levels were investigated in singleton pregnancies of 75 diabetic women and 84 women with obstetric hepatosis. Fetal distress was demonstrated in 19 diabetic patients (25%) and in 18 cases of obstetric hepatosis (21%). Low urinary estriol correctly predicted fetal distress in 26% of the cases of diabetes and in 29% of the cases of hepatosis. False pathologic readings were found in 9% of pregnancies in either group. Diabetes was associated with higher than normal hPL levels with overlap of levels between cases with fetal distress and normal outcome. hPL levels were higher than normal and correctly predicted fetal distress in 2 of 18 cases of hepatosis (11%) with no false pathologic values. In diabetes, AFP predicted fetal distress in 2 of 4 cases in which a subsequent perinatal death occurred, and 1 additional case of fetal distress. False pathologic values were found in 4% of cases. Maternal AFP levels were normal in 2 cases of closed neural tube anomalies. In cases of hepatosis, AFP gave no information. In combination, estriol and AFP determinations gave correct information in 35% of diabetic pregnancies with pernatal morbidity or death. In hepatosis, estriol and hPL pointed out 33% of the cases of fetal distress.     

An evaluation of human placental lactogen levels in hypertension of pregnancy.

Maternal plasma levels of human placental lactogen (HPL) are decreased in hypertensive pregnancies and the concentration is related to the severity of the condition. Of infants who had HPL concentrations in the fetal danger zone (more than 2 SD's below normal mean) 75 per cent developed fetal distress, neonatal asphyxia or were light for dates. Patients who are identified in this way have lighter infants and placentae than their unidentified counterparts with normal HPL levels.     

Human placental lactogen, pregnancy-specific beta-1-glycoprotein and alpha-fetoprotein in serum in threatened abortion

The predictive value of HPL, SP1 and AFP in serum were determined in 109 women admitted to hospital because of vaginal bleeding in the 6th to 19th gestational week. The prediction of abortion based on the initial analysis from the day of admission was found to be 91.7%, 75.9% and 81.8% for HPL, SP1 and AFP, respectively. The corresponding values for prediction of successful outcome were 68.7%, 73.6% and 65.4%. The HPL and AFP determinations were, however, found to be valid only after the 9th and 12th gestational week, respectively. A highly significant positive correlation (r = 0.84, P less than 0.001) was demonstrated between HPL and SP1 suggesting that SP1 measurements might replace HPL in the evaluation of the prognosis in threatened abortion.     

Maternal plasma alpha-fetoprotein and low birthweight: a prospective study throughout pregnancy

Maternal plasma alpha-fetoprotein (AFP) was measured serially between 15 weeks gestation and term in 520 patients. Thirty-seven of these women were delivered of normal singleton infants with birthweights less than 2.5 kg. The median plasma AFP values in this group of women were highest between 15 and 20 weeks gestation and then declined steadily towards term. It is concluded that the use of maternal plasma or serum AFP in the early detection of low birthweight babies is optimal in the period most suitable for screening for fetal neural tube defects.     

Maternal plasma and amniotic fluid prolactin levels in normal and hypertensive pregnancy

Prolactin levels in the plasma and amniotic fluid of 121 normal pregnant women, 78 women with pre-eclampsia and 30 women with essential hypertension complicating pregnancy were determined by radioimmunoassay. Mean prolactin levels in plasma, but not in amniotic fluid, were significantly lower than controls in the group with pre-eclampsia (P less than 0.01) and in the group with essential hypertension (P less than 0.05). These findings suggest altered production and/or clearance of prolactin from the maternal compartment in these patients and may explain their increased response to pressor agents.