Computer-assisted analysis of normal second trimester fetal heart rate patterns

A software package for computer-assisted analysis of antenatal fetal heart rate (FHR) patterns has been commercially available from 1989. Reference ranges for the third trimester of pregnancy have been established. In order to obtain reference values for the second trimester, one hour FHR recordings were made between 20 and 29 weeks gestation in 77 women with uncomplicated pregnancies. There was a significant increase of (medium term) FHR variation and of the number of accelerations from 20 to 29 weeks (r = 0.48, p less than 0.01 and r = 0.34, p less than 0.01 respectively). The lower limit of normal FHR variation (mean--2 SD's) increased from 18 msec at 20 weeks to 28 msec at 28 weeks. Furthermore, a 30 minute recording appeared to be sufficient to obtain a reliable impression of FHR variation. Short term FHR variation, a measure of FHR variation that facilitates the identification of sinusoidal FHR patterns, also increased significantly between 20 and 29 weeks (r = 0.61, p less than 0.01). Delerations (greater than 20 beats/min and greater than or equal to 30 seconds) were present in 54% of the recordings and are a more or less common phenomenon at this age. It is concluded that during the second trimester FHR variation differs considerably from that in the third trimester. This should be taken into account in the interpretation of second trimester FHR records.     

Nasal bone biometry in the second trimester of gestation

OBJECTIVES: To determine physiological variability range of the analyzed biometrical parameters and to establish optimal circumstances for fetal nasal ultrasound biometry. To evaluate preliminarily the value of fetal nasal biometry in the screening for aneuploidy. DESIGN: Ultrasound measurement of nasal bones length and nasal width in healthy fetuses and in fetuses with common aneuploidies. MATERIALS AND METHODS: Measurements of the analyzed parameters were undertaken in 681 euploid fetuses and 9 fetuses with common aneuploidies. Nasal bones length was measured with accordance to the same set of rules as determined by Cicero et al. in their publication relating to the first trimester nasal bones assessment. Nasal width was measured in the coronal plane between the alae. RESULTS: Relationship between the examined parameters and gestational age was described. The normal variability range of the analyzed parameters was determined and percentile charts created. In three out of five examined fetuses with trisomy 21 the nasal bones length was below the 5th percentile. In one out of five trisomy 21 fetuses the nasal width was over the 95th percentile. Regrettably the paucity of data obtained from affected fetuses does not allow drawing statistically founded conclusions. CONCLUSIONS: Fetal nasal biometry seems to be a valuable screening marker of trisomy 21 in the second trimester, requiring further studies.     

Disposal arrangements for fetuses lost in the second trimester

Summary. In 1986, 28 consultant pathologists with a special paediatric or perinatal interest in the UK and Irish Republic supplied information on current disposal methods for fetuses lost in the second trimester (12–28 weeks gestation) and the facilities available to parents. In over half the hospitals surveyed no single method of disposal was employed, but most of the fetuses were incinerated. In six hospitals all fetuses were either buried or cremated; 25 hospitals had facilities for photography and 24 made special religious services available. Other facilities available in some centres included the provision of blessing cards and a'remembrance book'and the appointment of a bereavement counsellor. In five of the local crematoria or cemeteries a special plot of land was reserved for stillbirths and younger fetuses. The relative costs of these facilities are discussed.     

Disposal arrangements for fetuses lost in the second trimester

In 1986, 28 consultant pathologists with a special paediatric or perinatal interest in the UK and Irish Republic supplied information on current disposal methods for fetuses lost in the second trimester (12-28 weeks gestation) and the facilities available to parents. In over half the hospitals surveyed no single method of disposal was employed, but most of the fetuses were incinerated. In six hospitals all fetuses were either buried or cremated; 25 hospitals had facilities for photography and 24 made special religious services available. Other facilities available in some centres included the provision of blessing cards and a 'remembrance book' and the appointment of a bereavement counsellor. In five of the local crematoria or cemeteries a special plot of land was reserved for stillbirths and younger fetuses. The relative costs of these facilities are discussed.     

The variability of fetal breathing movements in normal human fetuses at term

With the use of a B-scan phase-locked tracking system, 108 observations of fetal breathing were performed on 97 normal antenatal patients at term. One hundred thirty-three recorded segments of fetal breathing movements were obtained. Breath-to-breath variability was analyzed in 79 segments and expressed as a coefficient of variability. The mean coefficient of variability was 28.6% ± 13.2%, and a histogram plot revealed a normal distribution. All fetuses had normal antepartum testing and all Apgar scores and neonatal courses were normal. The potential application of human fetal breathing variability as a test for fetal health is discussed.     

Ultrasonographic soft markers of aneuploidy in second trimester fetuses

ObjectiveTo evaluate ultrasound “soft markers” used in fetal genetic screening.OptionsUltrasound screening at 16–20 weeks is one of the most common genetic screening tests used during pregnancy. The practical concern for ultrasound screening is false-positive and false-negative results. The use and understanding of ultrasound soft markers and their screening relative risks are an important option in the care of pregnant women.IntroductionChromosomal abnormalities occur in 0.1–0.2% of live births, and the most common clinically significant aneuploidy among live-born infants is Down’s syndrome (trisomy 21). Soft markers of aneuploidy are nonspecific, often transient, and can be readily detected during the second and third trimester ultrasound. The most commonly studied soft markers of aneuploidy include a thickened nuchal fold, mild fetal pyelectasis, echogenic bowel, echogenic intracardiac focus and choroid plexus cyst. There is a great deal of interest in the ultrasound detection of aneuploidy, as evidenced by the large number of publications in the literature on this topic.     

First trimester embryonic/fetal heart rate in normal pregnant women

Objective: To establish reference ranges for first trimester embryonic/fetal heart rate in normal pregnant women. Materials and methods: This was a cross-sectional study. We performed ultrasonogram in 319 normal pregnant women, gestation age between 6⁺⁰ and 14⁺⁶ weeks and measured embryonic/fetal heart rates using M-mode. The embryonic/fetal heart rates were analyzed according to gestational ages (GA). Results: Data of 319 pregnancies were analyzed and the outcome revealed the mean of fetal heart rate according to gestational age. The mean embryonic heart rates during the 6th–7th week of gestation are lower when compared with the other gestational ages. At the 8th week of gestation, the embryonic heart rate is maximum. Then the embryonic/fetal heart rate gradually decreased to 161 beats/min at the 14th week of gestation. The regression equation for embryonic/fetal heart rate (beat/min) [y] according to GA (day) [x] was y = −53.124 + 6.1333x + (−0.0407)x ² (r ² = 0.525; P < 0.001). Conclusion: Embryonic/fetal heart rates during the 6⁺⁰ and 14⁺⁶ week of gestation are related to GA. Our reference ranges may be useful for further studies such as for prediction of adverse pregnancy outcome in threatened abortion.     

Prostaglandins: a factor triggering labor and fetal expulsion in the second trimester

A group of 17 women in labor and 19 undergoing therapeutic abortion (a total of 36 patients aged 19 to 39) were given 1 to 5 mg Enzaprost containing prostaglandin F2 (PGF2 alpha) made by Chinoin in 500 ml iv perfusion to induce labor. The average duration of labor was 18 hours and 48 minutes (24 hours 40 minutes for primiparae and 7 hours 35 minutes for multiparae). Delivery ranged from 15 to 30 minutes. In three cases cesarean section was performed. In 14 of 19 cases of abortion, the conventional method of induction was carried out with estradiol, castor oil, calcium, and oxytocic in iv perfusion. An average dose of 2 mg Enzaprost was given to primiparae undergoing abortion, and the average time of evacuation of the uterus was 21 hours. Multiparae received 2 to 12 mg Enzaprost and the average time of expulsion of the fetus was 16 hours and 45 minutes. In 2 cases the method failed. No instances of intolerance or secondary phenomena were observed. The results confirmed the qualitative advantages of PGF2 for triggering uterine contractions: short duration of dilatation (average 11 hours and 15 minutes), simple technique, diminished side effects, no uterine hypertonia, minimal bleeding, lack of post-partum and post-abortum infection, and the minimal number of days of hospitalization.     

Pattern of the normal human fetal heart rate

With an improved method for fitting baselines to human fetal heart-rate traces, the patterns of episodic variations, accelerations and decelerations were similar in 215 64-min records from normal pregnancies and in 95 with mild hypertension and normal outcome. The change in signal loss with gestational age, by Doppler ultrasound for recording heart rate, was entirely due to the greater loss in episodes of high heart-rate variation. The changes in the numbers and sizes of accelerations and decelerations with gestational age were described. There were many records which had only one or no acceleration at 28-33 weeks gestation (16.2%) or 34-41 weeks (7.3%). However, only two (0.7%) had episodes of high heart-rate variation lasting less than 10 min from 28 weeks onwards. The presence of these episodes, with clusters of fetal movements, is therefore likely to be a better numerical index of normality.     

Spontaneous resolution of severe fetal ascites in the second trimester: a case report

BACKGROUND: Fetal ascites is an infrequent anomaly. The prognosis for fetal and neonatal survival is poor, especially with the development of ascites before 24 weeks' gestation. The spontaneous remission of severe fetal ascites without intrauterine treatment, especially with an uncomplicated neonatal outcome, is extremely rare. CASE: A woman had sonographically documented fetal ascites at 19 weeks' gestation. The workup for immunologic and nonimmunologic causes was negative. Serial ultrasound examination showed ascites from 19 to 28 weeks' gestation. A complete resolution of the ascites was noted at 33 weeks' gestation. A normal male infant was vaginally delivered at 39 weeks' gestation. CONCLUSION: Spontaneous resolution of fetal ascites, with a good prognosis, can occur in cases with an idiopathic etiology.     

Pattern of the normal human fetal heart rate

Summary. With an improved method for fitting baselines to human fetal heart-rate traces, the patterns of episodic variations, accelerations and decelerations were similar in 215 64-min records from normal pregnancies and in 95 with mild hypertension and normal outcome. The change in signal loss with gestational age, by Doppler ultrasound for recording heart rate, was entirely due to the greater loss in episodes of high heart-rate variation. The changes in the numbers and sizes of accelerations and decelerations with gestational age were described. There were many records which had only one or no acceleration at 28–33 weeks gestation (16.2%) or 34–41 weeks (7.3%). However, only two (0.7%) had episodes of high heart-rate variation lasting <10 min from 28 weeks onwards. The presence of these episodes, with clusters of fetal movements, is therefore likely to be a better numerical index of normality.     

Amniotic fluid embolism in multiple pregnancy in the second trimester of gestation

A rare case of amniotic fluid embolism in the 26-th week of pregnancy is presented. After the McDonald operation for the repair of the incompetent cervix, a premature rupture of the membranes occurred. After a five-day period of amniorrhea an elevation of the body temperature over 39 degrees C was observed, as well as respiratory distress, cyanosis, and coma. It ended with the patient's death. The pathomorphological finding demonstrated the amniotic fluid embolism of the lung and brain arterioles.     

Unexplained second trimester oligohydramnios: a clinical-pathologic study

The importance of oligohydramnios in the absence of fetal malformations has been recognized because of the associated high risk for adverse pregnancy outcome. Pathologic dissections were performed on four fresh fetuses whose mothers were identified by ultrasound as having oligohydramnios and had no clinical history or physical evidence of vaginal leakage of amniotic fluid. The fetuses were all normal except for hypoplasia of the lungs and varying degrees of Potter's facies. The kidneys were histologically normal but had increased weight. The more widespread use of ultrasound may have allowed us to detect an earlier stage of a previously present type of pregnancy failure.     

Relation of fetal blood gases and data from computer-assisted analysis of fetal heart rate patterns in small for gestation fetuses

Summary. Fetal heart rate (FHR) monitoring and computer-assisted analysis were performed immediately before cordocentesis in 25 severely small-for-gestational age fetuses. There were significant associations between FHR variation and both umbilical vein blood Po₂ (  r= 0–66  ) and pH (  r=0.69  ). However, the wide scatter of values around the regression lines prevented accurate prediction of fetal blood gases from FHR patterns. Nevertheless, FHR variation <20 ms was always associated with severe fetal hypoxaemia and acidaemia.