BUKOVINIAN STATE MEDICAL UNIVERSITY
“Approved” on methodological meeting of Department of Obstetrics and Gynecology with course of Infant and Adolescent Gynecology
“___”______________________ 200_ year protocol #
The Head of the department
Professor
________________ O.A. Andriyets
METHODOLOGICAL INSTRUCTION for practical lesson
“Physiology of pregnancy. Perinatal care of fetus. Methods of examination of pregnant women. Obstetrics terminology”
MODULE 1: Physiology of pregnancy, labor and puerperium
CONTEXT MODULE 2: Physiology of pregnancy, labor and puerperium
Subject: Obstetrics and Gynecology
4 th
year of studying
2 nd
medical faculty
Number of academic hours – 4
Methodological instruction developed by: assistant Andriy Berbets
Chernivtsi – 2008
Theme: Obstetrics Terminology. Methods of Examination of Pregnant Women. Assessment of
Fetal Well-being
Aim: to know obstetrics terminology, the methods of external and internal examination of pregnant women. To be able to prescribe and assess of modern methods of diagnostics of fetal well-being in obstetrics for in-term revealing of pathological changes in pregnant woman's organism and fetal status; prescribe an adequate treatment to the pregnant women in the case of fetal hypoxia.
Professional motivation: learning the methods of obstetrics examination of pregnant women is necessary to diagnose and to estimate the given information. An appropriate interpretation of fetal well-being tests in light of the natural course of any antenatal problem provides a firm base on which decisions are made.
Basic level: Student must know:
1. Anatomic terminology in English and Latin
2. Methods of physical examination of patient.
3. The structure of fetal head (anatomy of the skull).
4. Conceptus , development.
5. Obstetric ultrasound examination and its assessment.
6. Fetal heart rate auscultation.
7. To prescribe an adequate therapy of fetal well-being impairment
STUDENTS
’
INDEPENDENT STUDY PROGRAM
I. Objectives for Students' Independent Studies
You should prepare for the practical class using the existing textbooks and lectures. Special attention should be paid to the following:
Obstetrical terminology. Methods of examination of pregnant women:
1. Definition of the obstetrics terms: attitude (habitus), presentation, position, variety (visus).
2. Definition of the terms: axis of fetus, axis of uterus, axis of pelvis.
3. Engagement (synclitic and asynclitic).
4. Auscultation of fetal heart sounds.
5. Vaginal examination.
6. Speculum examination.
7. Examination of abdomen (Leopold Maneuvers).
8. Ultrasonic assessment of the fetus.
Assessment of fetal well-being:
1. Obstetric ultrasound examination.
2. Investigation of discharge from breast glands on the gestational age of pregnancy.
3. Electronic fetal monitoring.
4. Biophysical profile of the fetus.
5. Test for revealing of amniotic fluid.
6. Functional diagnostic's tests.
7. Invasive methods of assessment of fetal status: cordocentesis, phetoscopy, amnioscopy, amniocentesis.
Key words and phrases: habitus (attitude), lie, presentation, the position, variety, axis of fetus, axis of uterus, axis of pelvis, synclitism and asynclitism, engagement; Leopold's Maneuvers, speculum and vaginal examination. Assessment of fetal well-being, fetal hypoxia, biophysical profile of fetus.
Summary
Obstetrical terminology
The attitude refers to the relationship of parts of the fetus to one another (fetal head is flexed on fetal chest, thighs are flexed on fetal abdomen).
The lie of the fetus is the relationship of long axis of the fetus to the long axis of the uterus and is either longitudinal or transverse. In longitudinal lie fetal and uterus axes corresponds. When fetal and uterus axes cross at 45- degree angle - an oblique lie is formed. At transverse lie fetal and uterus axes cross at 90- degree angle Longitudinal lies are present in over 99% of labor at term.
The presentation indicates that portion of the fetus that overlies the pelvic inlet. Presenting part is the portion of the fetus that descends first through the birth canal (lowest in the birth canal).
When the lie is longitudinal, the presenting part is either the head (cephalic) or breech.
The position refers to the relationship of definite part of the fetus to the right or left side of maternal pelvis. With each presentation there may be two position, right or left. The occiput, chin and sacrum are the determining points in vertex, face and breech presentation, respectively.
Variety (visus) - the relation of the given portion of the presenting part to the anterior and or posterior portion of the mother's pelvis. Since there are two position, it foiiows that there must be
six varieties for each-presentation. The presenting part in any presentation may be either the left and right occipital (LO,RO),left and right mental (LM,RM),and left and right sacral (LS,RS) presentations. Since the presenting part in each of the two positions may be directed anteriorly, or posteriorly.
Engagement exists when the bi parietal diameter of the fetal head have passed the plane of the pelvic inlet. If at the time of engagement, the sagittal suture is midway between the pubic symphysis and the promontory of the sacrum in a transverse position, the head is said to be synclitic. In the sagittal suture rides anteriorly or posteriorly, the fetal vertex is asynclitic
(anterior asynclitism, posterior asynclitism).
Examination of pregnant women
Abdominal palpation: Leopold's maneuvers.
The first maneuver: the examiner hands palpate the fundal area and distinguish which part of the fetus occupies the fundus. Importance: estimation of gestational age of the pregnancy and fetal lie.
The second maneuver is accomplished when hands are placed on either side of the abdomen to determine on which side the fetal back lies. Importance: estimation of fetal lie, position, variety, amount of amniotic fluid, fetal movement.
The third maneuver is done with a single examining hand placed just above the symphysis.
Importance: determination presentation and presenting part. The presented part is grasped between the thumb and third finger.
The fourth maneuver is done with the examiner facing the patient's feet and placing both hands on either side of the lower abdomen just above the inlet. Importance: determination of fetal head station (relation of presenting part to the pelvic inlet).
Vaginal examination. In vaginal examination a doctor should examine vaginal walls; dilation, effacement, consistency and position of the cervix; presence of amniotic fluid; fetal presentation and position, pelvis also.
To determine presentation and position by vaginal examination, it is advisable to pursue a definite routine that consists of three maneuvers as:
Two gloved fingers are introduced into vagina and carried up to the presenting part.
Differentiation of vertex, face and breech presentation is then readily accomplished.
If the vertex is presenting part, the examiner's fingers are introduced in the posterior aspect of the vagina. The fingers are then swept over the fetal head toward the maternal symphysis. The examiner's fingers must cross the sagittal suture, and its course is outlined, with small and large fontanels at the opposite ends.
The positions of the two fontanels then are ascertained, ie, anterior and posterior.
Auscultation. In cephalic presentation, the point of maximal intensity of fetal heart sounds is usually midway between the maternal umbilicus and the anterior-superior spine of her ilium.
Employing ultrasonography, the fetal head and body can be located usually without difficulty.
Ultrasonic dating of the pregnancy and an ultrasonic fetal survey to detect gross abnormalities have been recommended in some clinics as a routine part of early prenatal care. Routine ultrasonography is most cost -effective in patients in whom the date of the last menstrual period is uncertain and in patients with a family history of congenital anomalies. Considerable individuaHzation should be exercised in making the decision to order this evaluation. If ultrasonography is performed, it is most informative between 18-20 weeks.
Structural defects that have been diagnosed with this technique include craniospinal abnormalities ( e.g., anencephaly, hydrocephaly, spina bifida, microcephaly), gastrointestinal anomalies ( e.g., omphalocele, gastroschisis), excretory system anomalies (e.g., renal agenesis, renal dysplasia, urinar obstruction), skeletal dysplasia and congenital heart defects.
Endovaginal ultrasonography is used primarily in the first trirneste to establish fetal viability.
Assessment of fetal well-being
Assessment of fetal well-being includes maternal perception of fetal activity and several tests using electronic fetal monitors and ultrasonography
Tests of fetal well-being have a wide range of uses, including the assessment f fetal status at a particular time and the prediction of fetal status for varying time intervals, depending on the test and the clinical situation.
An active fetus is generally a healthy fetus, so that quantification of fetal activity is a common test of fetal well-being. If, for example, the mother detects more than four fetal movements while lying comfortably and focusing on fetal activity for 1 hour, the fetus is considered to be healthy.
Techniques using electronic fetal monitoring and ultrasonography are most costly, but also provide more specific information. The most common tests used are the nonstress test, the contraction stress test (called the oxytocin challenge test if oxytocin is used), and the biophysical profile.
The nonstress test (NST) measures the response of the fetal heart rate to fetal movement.
Interpretation of the nonstress test depends on whether the fetal heart rate accelerates in response to fetal movement. A normal, or reactive, NST occurs when the fetal heart rate increases by at least I5bpm over a period of 15 seconds following a fetal movement. Two such accelerations in a
20-minute span is considered reactive, or normal. The absence of these accelerations in response to fetal movement is a nonreactive NST. A reactive NST is generally reassuring in the absence of
other indicators of fetal stress. Depending on the clinical situation , the test is repeated every 3 to
4 days or weekly. A nonreactive NST must be immediately followed with further assessment of fetal well-being.
Whereas the nonstress test evaluates the fetal heart rate response to fetal activity, the contraction
stress test (CST) measures the response of the fetal heart rate to the stress of a uterine contraction. With uterine contraction, uteroplacental blood flow is temporary reduced. A healthy fetus is able to compensate for this intermittent decreased blood flow, whereas a fetus who is compromised is unable to do so, demonstrating abnormalities such as fetal heart rate decelerations. If contractions are occurring spontaneously, the test is known as a contraction stress test; if oxytocin infusion is required to elicit contractions,the test is called an oxytocin challenge test (OCT). The normal fetal heart rate response to contractions is for the baseline fetal heart rate to remain unchanged and for there to be no fetal heart rate decelerations.
The biophysical profile is a series of five assessments of fetal well-being, each of which is given a score of 0 or 2. The parameters include a reactive nonstress test, the presence of fetal movement of the body or limbs, the findings of fetal tone (flexed extremities as opposed to a flaccid posture). And an adequate amount of amniotic fluid volume. Perinatal outcome can be correlated with the score derived from these five parameters.
A score of 8 to 10 is considered normal, a score of 6 is equivocal requiring further evaluation, and a score of 4 or less is abnormal, usually requiring immediate intervention
Table 1. Biophysical profile
Biophysical Score
Variable
Explanation
Fetal breathing movements
(FBM)
Norma 1 = 2 At least 1 FBM of at least 30 seconds duration in 30 minutes
Abnormal = 0
Gross body movement
Normal = 2
No FBM of at least 30-seconds duration in 30 minutes
At least 3 discrete body /limb movements in 1 30 minutes
Abnormal = 0 2 or less discrete body /limb movements in 30 minutes
Fetal tone Normal = 2 At least 1 episode of active extension with return to flexion of fetal
Of muscles limbs/trunk or opening/closing of hand
Reactive fetal heart rate
Abnormal == 0 Either slow extension with return to partial flexion or movement of
Normal = 2 limb in full extension or no fetal movement
Reactive NST
Qualitative
Abnormal = 0 Nonreactive NST amniotic fluid volume
Normal = 2 At least 1 pocket of amniotic fluid at least 1 cm in two perpendicular planes
Abnormal = 0 No amniotic fluid or no pockets of fluid greater 1 than 1 cm in two perpendicular planes
IL Tests and Assignments for Self
— assessment.
Multiple Choice.
Choose the correct answer / statement:
1. The most common fetal lie found during early labor is: A - Oblique;
B - Transverse;
C - Vertex;
D ~ Longitudinal.
2. The most common fetal presentation found during early labor is: A - Oblique;
B - Transverse;
C - Vertex;
D - Longitudinal.
3. What is presentation?
A - Relationship of the fetal presenting part to the right and left side of the maternal pelvis;
B - Relationship of the long axis of the fetus with the uterine long axis;
C - Portion of the fetus lowest in the birth canal;
D - Part of the fetus that is most easily palpable on abdominal examination;
4. Leopold's maneuvers are used to establish all of the following except:
A - Fetal gender; B - Fetal lie; C - Fetal presentation; D - Fetal position; E - Fetal movement.
5. What do we identify carrying out the third Leopold's Maneuver?
A - part of the fetus which occupies the fundus of the uterus
B - fetal back;
C - the lie of the fetus;
D - the presenting part;
E - the position of the fetus.
Real - life situations to be solved:
6. While perfoming the first Leopold maneuver the physician palpates in fundal area irregular and soft part; carrying out third maneuver determine round, firm and balloting part. What is the presentation of the fetus?
7 While examining the abdomen of pregnant woman physician identifies the longitudinal lie of the fetus, head presentation, left position anterior variety.
Where is the best place for auscultation of the fetus heart sounds?
What is the normal fetal heart rate?
III. Answers to the Self- Assessment.
1. D. 2. C. 3. C. 4. A. 5.D. 6. Cephalic presentation. 7. Auscultation should perform on the abdominal left side and lower the umbilicus. The normal heart rate of fetus is 120-140 beats per minute.
Students must know:
1. Obstetrics terminology.
2. Examination of the abdomen ( Leopold's maneuvers).
3. Pelvic examination.
4. The landmarks of fetal skull, segments of fetus heard.
Students should be able:
1 .
To take history (anamnesis).
2. To perform objective examination of pregnant woman.
3. To perform Leopold's maneuver.
4. To identify the lie, position and presentation of the fetus.
5. To perform the auscultation, vaginal and speculum examination.
6. To estimate the given information.
References:
1. Danforth's Obstetrics and gynaecology. - Seventh edition.- 1994. - P. 289-304.
2. Obstetrics and gynaecology. Williams & Wilkins Waverly Company. - Thirdl Edition.- 1998.
- P. 118-130.
3. Basic Gynecology and Obstetrics. - Norman F. Gant
7
F. Gary Cunningham, -j 1993. - P. 328-
397.
4. Obstetrics and gynecology. - Pamela S.Miles, William F.Rayburn, J.Christopher. Carey. -
Springer-Verlag New York, 1994. - P, 30-34.