Second-trimester screening for fetal abnormalities
Hung N. Winn, Frank A. Chervenak, Roberto Romero in Clinical Maternal-Fetal Medicine Online, 2021
After the fetal head is evaluated, the fetal facial structures are examined. A range of genetic syndromes and disorders are associated with characteristic facial features, and thorough evaluation of the fetal face can aid in supporting or excluding their diagnosis. Obtaining a combination of coronal, sagittal, and axial views is necessary to complete the facial evaluation. To begin, a fetal profile should be obtained in the sagittal plane (Fig. 5). This allows for proper visualization of the frontal bone, nasal bone, and fetal chin. Absent or shortened nasal bone may indicate fetal aneuploidy and will be discussed later in this chapter. Micrognathia has also been associated with a variety of genetic syndromes and disorders, making characterization of the fetal chin important. The fetal nose and lips should be imaged in coronal plane and the anterior palate should be visualized to exclude cleft lip and palate.
Obstetric Management of Intrauterine Growth Retardation
Asim Kurjak, John M. Beazley in Fetal Growth Retardation: Diagnosis and Treatment, 2020
Biparietal diameter measurements — A great variance in fetal head size is seen in the third trimester of pregnancy, and this makes BPD measurements unreliable as a single test to predict IUGR.72,73 In fetuses suffering from asymmetrical growth retardation, where “brain sparing” commonly occurs, the fetal head size can remain within normal limits for a long time.74 These high-risk fetuses may consequently go undetected until late in the pathological process when this method is used. Campbell has reported that static head growth for 3 weeks is compatible with intrauterine survival, but this may be at the expense of increased morbidity in this group of infants.74,75 In order to detect symmetrical growth retardation, serial scanning is necessary to observe the slow growth rate characteristic of this type of growth retardation, and an earlier diagnosis can be made if a dating ultrasound scan was performed in the first half of the pregnancy.
Biomechanical Factors In Fetal And Maternal Changes In Pregnancy And Labor
Sujoy K. Guba in Bioengineering in Reproductive Medicine, 2020
In the initial stages of labor it is the uterus which exerts force on the fetal head. A phase then is reached when the head abuts against the maternal pelvic walls and there are force interactions between the pelvic wall and the head. The cervix too presses onto the head during the passage through the cervical opening.1 Structures to be considered are then the fetal head, maternal uterus, cervix and the pelvic walls. Information in this respect have been compiled by a large number of anatomical investigations. By palpation as well as X-ray observations the movement of the fetal head describing the descent, rotation and flexion have been obtained.2 Contraction of the uterus and cervical dilatation have also been monitored as outlined in Chapter 9 and a later section in the present chapter of this book respectively.
Post Mortem Diagnosis of Blake's Pouch Cyst: A Presentation of Distended Cyst at Necropsy
Published in Fetal and Pediatric Pathology, 2018
Srividya Sreenivasan, Vishnu Sawant, Joy Ghoshal
A 27-week gestation stillborn female was spontaneously delivered to a 24-year-old primigravida of a nonconsanguineous marriage. An ultrasound at 26 weeks gestation revealed a 21 × 16 mm cyst in the posterior cranial fossa (Figure 1), with lateral ventricular enlargement. The fetal head size was appropriate for gestational age. At autopsy, a thin walled clear fluid-filled 21 × 16 mm cyst was postero-inferior to the cerebellum (Figure 2). During further dissection the cyst spontaneously regressed in size, with an intact cyst wall, suggesting its communication with the 4th ventricle and no overt communication with the subarachnoid space. Blood vessels and choroid plexus were present on the upper part of the cyst wall (Figure 3). Dissection confirmed that the cyst wall was the roof of the 4th ventricle. Histologically, the cyst wall was composed of ependyma with choroid plexus, and no neurons. Both the lateral ventricles were distended with thinning of the cerebral cortex. The third ventricle and aqueduct of Sylvius appeared normal in caliber.
Systematic review of the literature on triclosan and health outcomes in humans
Published in Critical Reviews in Toxicology, 2018
Michael Goodman, Daniel Q. Naiman, Judy S. LaKind
When a clinical trial is unethical or not feasible, cohort studies may present the best design option. As TCS exposures vary over time, even cohort studies in which exposure assessment preceded outcome ascertainment may not be able to adequately establish the temporal relationship, thereby limiting causal inferences. Consider, for example, cohort studies that examined the association between prenatal TCS levels and neonatal endpoints (e.g. birth weight, head circumference, or anogenital distance) assessed either at birth or postnatally. Fetal head circumference increases from about 10 to 22 cm between gestational weeks 14 and 24, at a rate of 2.2 cm per week. In the next 10 weeks of gestation, the average head circumference growth rate is around 0.7 cm/week; and for the remainder of a full-term pregnancy (34–40 weeks), the growth slows down further to about 0.5 cm/week (Papageorghiou et al. 2014). If a maternal urine sample is obtained in late, rather than early, pregnancy, the resulting measure may miss the most relevant exposure window, and the study may be unable to establish the true temporal relation between the exposure and the outcome.
Extraperitoneal versus transperitoneal cesarean section: a retrospective study
Published in Postgraduate Medicine, 2023
Chao Ji, Meng Chen, Yichen Qin
The traditional method of head delivery requires repeated pressure of the uterine fundus, which increases the pain of puerpera and may increase the rate of surgical complications, indirectly affecting prognosis. A longer time for fetal head delivery leads to a higher risk of complications, such as neonatal asphyxia and amniotic fluid inhalation syndrome caused by external stimulation to the fetus [19]. Therefore, the fetal head should be delivered quickly after uterus incision and the respiratory tract should be fully cleaned. One major difficulty of ECS is the delivery of the fetal head. In this study, no significant impact of ECS was presented on the measurable parameters of the newborn, which might be attributed to the use of obstetric forceps in our hospital for fetal head delivery. The left and right leaves of forceps are, respectively, placed on the left and right sides of the fetal head, and a sufficient and smooth force is used to deliver the head. This approach can effectively shorten the delivery duration of the fetal head.