[The fetal adrenal gland in risk pregnancy].

Introduction: The role of the adrenal gland in the metabolism of foetus and its role in maturation of foetal organs are the principal motives for paying more attention to this vital organ, which is still a great enigma for gynaecologists. The control of the gland is important in normal as well as in risk pregnancies. Of the entities that most often imperil the growth of foetus and adrenal glands are diabetes and hypertension in pregnancy. A consequence of the maternal diabetes may be macrosomy of foetus manifested by increase in foetal body mass and enlargement of organs sensitive to increased concentration of insulin in the foetal blood [6], i.e., the liver, fat tissue, lungs, adrenal glands, heart. Brown and Singer (1988) [2] established that adrenal glands of foetus are imperiled in pregnancies complicated by mother's hypertension. Their conclusion was derived from pathologic findings in foetuses from unsuccessful pregnancies of patients with hypertension. The glands were of reduced sizes. The way to perform precise measuring of glands, which are of dilapidated composition during post mortem examination, is not quite acceptable, since during the manipulation the size may, to some degree, be altered. By introduction of the ultrasound method in medical practice the problem of biometry has been overcome. Besides measuring, of great importance for the study of physiology of the gland is also the analysis of the foetal fluid and foetal blood. The first successful measuring of the adrenal gland of foetus by ultrasound was performed in mid 80s of the last century by Jeanty and Romero [3] via transabdominal path. The aim of our study is the comparison of foetal adrenal glands in normal and high-risk pregnancies.

Material And Methods: During a prospective follow-up carried out at the Institute of Gynaecology and Obstetrics, Clinical Centre of Serbia, 213 patients, aged from 19 to 44 years were examined. Gestation periods were from the 11th to the 40th week. We divided the patients in 3 groups. The first group consisted of 131 patients with no pathologic changes and whose children were born alive. The second group was formed of 75 pregnant women in whom the course of pregnancy was impaired and disorders in the foetal. From these pregnancies the children were born alive. The third group was composed of 7 patients in whom abortion was indicated. The measured values of foetal adrenal glands diameter in the first group (131 patients), were used for making a nomogram of the glands growth. The measuring was performed with ultrasound apparatus "Toshiba 100 SSA". Transabdominal examination with a probe of 3.75 MHz and transvaginal examination with probes of 5 and 7 MHz were performed. Since the picture of the adrenal gland resembled an ellipse, on the basis of measured diameters and using the formula for circumference of this geometric figure [O = (d1 + d2) x pi/2], we obtained the desired value, which increased with advancement of pregnancy. Patients included in the study were with one-foetus pregnancy, whose last menstruation was precisely dated. Data are presented in a chart. For analysis of the obtained data, in addition to parameter methods, we also used the linear correlation and regression and one-factor analysis of variance. Data base analysis was made in the SPSS for DOS package.

Results: In making a nomogram of adrenal glands growth of a foetus old between 11 and 40 weeks, 131 of 213 patients were included, while the other foetuses were excluded as they belonged to high-risk pregnancies. Correlation of the growth of adrenal glands circumference and gestation period of pregnancy are also highly statistically important. The correlation coefficient of the straight line which represents this dependancy, is R = 0.8916, for the significance level of p < 0.01 (GRAPH 1). We observed how the course of pregnancy influenced the growth of foetal adrenal gland in normal pregnancies and in foetuses impaired by a pathological pregnancy course. By the method of one-way variance analysis, we obtained the value of the test, which was F = 2.79; p = 0.07. The graphical presentation of adrenal glands of a foetus in the appropriate week of gestation revealed that dimensions of glands in pregnancies impaired by diabetes were larger than those in normal gestations, and that they were at the top of border value of +2 SD or even over this limit. The statistically obtained value was F = 1.81; p > 0.05 (p = 0.06 and it was close to the border value for the significance level of p < 0.05); however, for glands of pregnancies complicated with hypertension the value was F = 1.61; p = 0.063 and the border value near -2 SD. Data are presented in a chart, regarding nomograms and adrenal glands of risk pregnancies.

Discussion: In 1993 Bronstein and colleagues [1] proved that the route of visualization of an adrenal gland was not only transabdominal. They succeeded in detecting the glands by transvaginal ultrasound examination in the 12th week. Jeanty and Romero [3] performed a successful transabdominal visualization in the 23rd week of gestation. By ultrasound prenatal examination we can determine the existence of hyperplasia of adrenal glands (Kelnar 1993) [5]. With ultrasound examination we can also diagnose tumours of the medulla, such as neuroblastoma (Jennings and colleagues 1993) [4]. In our study we reported on the visualization and growth of foetal adrenal glands in the period from the 11th to the 40th week of gestation. We presented the growth of foetal adrenal glands in normal gestations with the growth nomogram. The coefficient of correlation of adrenal glands circumference was R = 0.8916. The level of significance was p < 0.01. In conclusion, we can say that risk factors in pregnancy could impair the growth of adrenal glands. We have found that foetal adrenal glands in pregnancies impaired with maternal diabetes were hypertrophic, while those in pregnancies impaired with hypertension were almost at hypotrophic border. The nomograms of adrenal glands growth were of clinical importance, since they help us to control the state of a foetus in high-risk pregnancies.

Conclusion: Improvement of the methods used in prenatal diagnosis will contribute to a timely detection of a diseased foetus, and will be the first step in its recovery. Regulating the pathological condition of the mother will surely contribute to decrease the risk of delivering children with an increased risk of morbidity.