J. Janssens

Quantitative evaluation of fetal heart rate patterns

Abstract Beat-to-beat arrhythmias of fetal heart action can be hardly analysed with ordinary paper tape recordings of the fetal tachogram. This problem can be circumvented by the use of automatic processing methods by which the irregularity can be quantified and different types of irregularity can be diagnosed. Two patients are discussed. The tentative diagnosis in the first case was wandering pacemaker, and in the second one sino-atrial block.

The pathogenesis of placental infarction

Abstract Multiple or serial histologic sections of 536 well-defined infarcts obtained from 1,240 consecutively delivered placentas were examined for possible pathologic changes related to circulatory obstruction in fetal stem vessels or maternal uteroplacental vessels. Significant changes in fetal stem vessels could not be demonstrated. Most of the uteroplacental arteries showed evidence of obstruction; thrombosis was a frequent finding. It is concluded that a placental infarct consists of necrosis of a fetal cotyledon caused by occlusion of the supplying uteroplacental artery.

Quantitative evaluation of fetal heart rate patterns: II. The significance of the fixed heart rate during pregnancy and labor

Abstract The heart rate patterns of anencephalic fetuses and of normal fetuses after administration of sedatives to the mother show a silent fetal heart rate pattern. In both cases, analysis of such a heart rate pattern by processing methods, shows absence of short term irregularity and the presence of only a small amount of long term irregularity.

Influence of dydrogesterone on the activity of the nonpregnant human uterus

Abstract In several phases of the menstrual cycle uterine activity is characterized by distinct patterns. There is a typical “ovulatory pattern.” During drug-induced anovulatory cycles the “ovulatory pattern” is no longer present, whereas during dydrogesterone treatment no interference with the “ovulatory pattern” is seen.

The fetal autonomic nervous system, the fetal heart rate and the beat-to-beat irregularity

In the exteriorized fetal lamb an experimental study on the influence of the fetal autonomic nervous system upon the heart rate pattern is described by means of blockage of the cholinergic, alpha-adrenergic and beta-adrenergic system. The alpha-adrenergic system proved to have no effect upon heart rate. The beta-adrenergic system had a positive chronotropic effect and the parasympathetic system had a negative chronotropic effect. Beat-to-beat irregularity was independent of a functional alpha-adrenergic system, but at a high basic heart rate disappeared completely after cholinergic blockage and at a low rate after beta-adrenergic blockage. It is concluded that most probably the beat-to-beat irregularity is the result of the competition of the enhancing influence of the beta-adrenergic system and the inhibiting influence of the cholinergic system on fetal heart rate.

Accurate pressure recording in the non-pregnant human uterus. A comparison of open and closed tip catheters

Abstract The accuracy of recording intrauterine pressure in the non-pregnant uterus with open (sponge) or closed tip (balloon) catheters was investigated in vivo and in vitro. From the studies in which the manometrically induced pressure changes in an “artificial uterus” were recorded, the conclusion is reached that open tip catheter recordings are accurate and closed tip catheter recordings are not.

A comparison of digital and nondigital analysis of contraction records obtained from the nonpregnant uterus in vivo.

Abstract A method is described to record on analogue and digital tape contractions obtained from the nonpregnant human uterus in vivo. A digital program is computed to calculate parameters comparative to: amplitude, interval, and duration of the contractions and active pressure area (APA) and linear displacement analysis (LDA) of 410 second segments of the records. Comparison of the results of the digital and of the conventional calculating method shows identical data as far as amplitude, interval, and duration of the contraction are concerned; results of APA and LDA with both methods differ to a large extent. Some difficulties in definitions and calculation procedures of the parameters of the contractions are discussed.

Accurate Pressure Recording in the Non-Pregnant Human Uterus

In order to resolve some of the conflicting opinions concerning the relative accuracy of open vs. closed systems used in recording uterine activity, the various types of catheter recording systems wer

Trend Detection in the Fetal Condition

THE CONTINUOUS recording of signals from the fetus in utero is only possible by using signals originating from the fetal heart. The fetal heart rate gives more information on the fetal circulatory condition than any other parameter associated with heart function. Therefore, in assessing the fetal condition during pregnancy and labor, the exact measurement and quantitative analysis of fetal heart rates and their disturbances are the primary objectives.

Marriage and childbearing in relation to cervical cancer.

In order to assess any correlation between cervical cancer and age at marriage and childbearing, matched control groups were formed. From the comparison it appears that cervical cancer patients are more likely to be married and to have married at an earlier age than control women. In the same age groups at marriage there was no difference in the number of children between the cervical cancer patients and the control women. It appeared that cervical cancer patients had their first child earlier than control women. There were more illegitimate children in the cervical cancer groups than in the control groups, but after the wedding date there were no differences between the cervical cancer groups and the control groups in the time between the wedding date and the date of birth of the first child. The data show that after pregnancy or childbirth, in particular at an early age, there is a greater risk of getting a cervical cancer. By contrast, nulliparous married women seem to have a low risk of cervical cancer.