3. • A 40-year-old gravida 2 para 1 woman presented in
active labor after an uncomplicated pregnancy and
adequate prenatal care. (“Gravida” refers to the number
of pregnancies and “para” refers to parity, the number of
births. This is often abbreviated “G2 P1”. After the baby
is born, the designation will be changed to G2 P2 if the
baby is born, or G2 P1 Ab1 if there is a stillbirth.) The
infant was born by normal spontaneous vaginal delivery
(abbreviated NSVD) and Apgar scores are an estimate
of the baby’s health at birth, and ranges from 0 for a
baby born dead to 10 for a very healthy infant.) The baby
was taken to the newborn nursery and the placenta was
retained for possible examination.
4. Placentas should be sent to pathology if any of the conditions
discussed in lecture are suspected, if there is a history of
spontaneous abortions in the mother, if the baby goes to the
Neonatal intensive care unit, if there is an abnormality in the baby, a
history of maternal diabetes, or if the estimated gestational age of
the baby is less than 36 weeks. The placentas in your lab reflect
some of the findings possible in a case such as the one described
above.
Exercise 1:
Locate all of the gross structures listed in Fig. 1 in the core notes.
Describe any abnormalities present. If you have a twin placenta,
locate the dividing membranes and determine what type of twinning
is present.
5. Exercise 2: Locate all the structures listed in Fig. 2 C, and together with the gross
placentas, describe the blood flow between mother and fetus.
7. CASE TWO
• Clinical Summary: The patient is a 28-year-old G2 P1 presenting in
labor at 42 weeks gestation. The patient received adequate prenatal
care and the pregnancy was unremarkable. Spontaneous rupture of
membranes occurred, revealing a thick, dark green, slimy material in
the amniotic fluid. Delivery progressed rapidly and fetal monitoring
revealed severe fetal distress. The Apgar score of the infant at 1
minute was 1, and suction of the oropharynx was performed. A
similar greenish material was noted, and vigorous resuscitation was
performed. The infant was intubated, but remained cyanotic and
bradycardic. The baby died and an autopsy was performed. No
congenital abnormalities were noted. Examination of the lungs
revealed a dark red cut surface, and abundant green mucus in the
bronchi. The first slide of case 2 shows a bronchus distended by
squames, which are part of the normal amniotic fluid. Because of the
distress in utero the fetus inhaled an increased amount of fluid, so
more squames than normal are seen in the lung. Some of the
macrophages in the lung appeared to contain greenish pigment.
8. • Question 1:
• What is the green material described
above? Where did it originate?
• Question 2:
• Why did the baby die?
9.
10.
11. Gross Pathology: The gross placenta is
seen in the next slide. The underlying
cotyledons do not show any gross
abnormalities.
Question 3:
What is the most important gross finding?
12.
13. Microscopic: The next slide shows a section of the fetal membranes.
The pathologic findings in this placenta are seen only along the fetal
surface of both the membranes and the placenta itself. The amnion
is occasionally interrupted by small clumps of eosinophilic material.
This material may be the size of two or three cells. In the connective
tissue immediately below the amnion, there are numerous
macrophages. At high power, one can see that the macrophages
have phagocytized granular, golden-tan pigment.
Question 4:
What do you think is the nature of this pigment?
Question 5:
Usually, these macrophages are only seen in the amnion and
underlying connective tissue. What do you think is the significance
of the pigmented macrophages when they are present deep within
the chorion?
16. CASE THREE
• The mother is a 26-year-old G2 P1 O+, rubella immune,
VDRL nonreactive woman with spontaneous rupture of
membranes after approximately 32 weeks gestation.
Ultrasound showed that the fetus was in a breech
position. An emergency cesarean section was done for
fetal distress. The baby was born limp and cyanotic with
a heart rate of less than 100 and no spontaneous
respirations. Apgar scores were 1 at 1 minute and 6 at 5
minutes. Resuscitative measures were instituted and the
baby was placed in the neonatal intensive care unit
(NICU). The baby continued to do poorly with unstable
vital signs. Life support was withdrawn and the patient
died on the second day of life.
• An autopsy was performed on the infant, and the major
findings were within the lungs. Grossly, the lungs were
heavy, consolidated and dark purple-red. A
photomicrograph of the lungs is shown in the first 2
slides of case 3.
17. Question 1:
What are the important findings in the first
slide?
Question 2:
What are the important findings in the
second slide?
Placental Pathology:
The major gross finding was thick, opaque
fetal membranes with a foul odor.
24. Microscopic pathology:
Photomicrographs of the fetal surface of the placenta including a blood
vessel in the chorion are seen in slides 3 through 6 of case 3.
Question 3:
What is the major microscopic feature in the first of the three slides?
Question 4:
What is common to both the placental surface and lungs?
Question 5:
What is the likely explanation for the premature rupture of membranes?
Question 6:
Can you explain the correlation between the fetal pneumonia and the
chorioamnionitis?
Question 7:
What is the mechanism of bacterial infection in most cases of
chrioamnionitis?
25. Fetal Lung Injury
• Normal – No injury
– Fetus normally inspires amniotic fluid in utero
• Ascending Vaginal Bacterial Infection
– Chorioamnionitis – Inflammation of Fetal Membranes
– Membrane Proteolysis and Premature Rupture
• Fetal Prematurity
– Bacterial Infection of Amniotic Fluid
• Fetal Pneumonia- Infection
• Meconium Aspiration
– Premature Meconium Passage From Fetal GI Tract
– Inspiration of Meconium-contaminated Amniotic Fluid
• Fetal Pneumonia - Chemical
