Placental Pathology and Bleeding

Question 1

early-term

Answer 1

37.0-38.6 GA

Question 2

full-term

Answer 2

39.0-40.6 GA

Question 3

late-term

Answer 3

41.0-41.6 GA

Question 4

post-term

Answer 4

42.0+ GA

Question 5

What are risk factors of post-term birth?

Answer 5

1) primigravida
2) hx post-term pregnancy
3) male fetus
4) obesity

Question 6

What are complications of post-term birth?

Answer 6

1) oligohydraminos –> cord compression, chronic oxygenation problems, growth restriction
2) meconium aspiration
3) macrosomia –> lacerations, tears, hemorrhages

Question 7

What is the management plan for low-risk, late-term pregnancy?

Answer 7

1) @41 weeks: NST and BPP or modified BPP
2) repeat NST in 72h
3) induce by 42 weeks

Question 8

What is a low-cost, low-risk, vital mode of fetal surveillance?

Answer 8

fetal kick counts @ 28-32 weeks

Question 9

When does ACOG recommend IOL?

Answer 9

after 42.0 and by 42.6 GA

Question 10

placenta circumvallate

Answer 10

basal plate smaller than chorionic plate –> membranes doubled back on themselves (white ring)

do not know significance

Question 11

accessory (succenturiate) lobes

Answer 11

vessels from umbilical cord on fetal side travel to separate lobe on placenta

often associated w/ PP hemorrhage!

Question 12

vasa previa

Answer 12

fetal blood vessels over cervical os

Question 13

management of vasa previa

Answer 13

1) @ 28-30 weeks: NST 2x/week
2) hospitalization in 3rd tri – administer antenatal corticosteroids
3) C/S @ 34-36 weeks

Question 14

placenta accreta

Answer 14

abnormal placental attachment d/t absence of decidua basalis and incomplete development of fibrinoid (Nitabuch) layer –> increased trophoblast invasion into decidua

Question 15

What are the 3 subsets of placenta accreta?

Answer 15

1) accreta vera: adherence to myometrium
2) increta: growth into myometrium
3) percreta: through uterine wall w/ placental attachment onto surrounding tissue (e.g. bladder, bowel)

Question 16

placental abruption

Answer 16

separation of placenta from uterine wall before delivery d/t rupture of maternal vessels in decidua basalis

Question 17

Differentiate b/w the two types of placental abruption

Answer 17

1) acute

2) chronic –> subchorionic = early in pregnancy; abruption = late in pregnancy

Question 18

What is the hallmark symptom of placental abruption?

Answer 18

“colicky” abdominal pain that does not go away

Question 19

When does placental abruption most often occur?

Answer 19

24-26 weeks

Question 20

What are risk factors for placental abruption?

Answer 20

1) HTN doubles risk
2) PPROM triples risk
3) C/S inc risk 30-50%
4) smoking; cocaine use
5) polyhydramnios
6) multiple gestation
7) unexplained, abnormally elevated alpha-fetoprotein (AFP)
8) maternal trauma (e.g. MCV, fall, assault)

Question 21

How is placental abruption managed?

Answer 21

OBSTETRIC EMERGENCY

1) varies based on fetal and maternal age/status
2) early abruption associated w/ IUGR in early pregnancy

Question 22

List the types of placenta previa

Answer 22

1) complete = over os
2) partial
3) marginal

Question 23

trophotropism

Answer 23

“movement” of low-lying placenta @~20wks

Question 24

What is the hallmark symptom of placenta previa?

Answer 24

painless bleeding in 2nd or 3rd trimester

Question 25

What is VITAL to avoid in the assessment of a pt presenting w/ bleeding?

Answer 25

NO digital exam if pt never had an U/S to confirm placental position

Question 26

What is appropriate management for acute bleeding and/or contractions?

Answer 26

hospitalization

Question 27

When is expectant management appropriate in previa?

Answer 27

- bleeding subsides --> birth can occur closer to EDD | - small abruptions @<34 weeks

Question 28

When should delivery be considered for pts with previa?

Answer 28

if near term - C/S for asymptomatic previa @ 36-27 weeks - immedate C/S for complicated previa

Question 29

small for gestational age

Answer 29

<10th percentile

Question 30

appropriate for gestational age

Answer 30

10th-90th percentile

Question 31

large for gestational age

Answer 31

>90th percentile

Question 32

intrauterine/fetal growth restriction

Answer 32

fetus that has not reached growth potential d/t genetic or environmental factors

Question 33

Besides risk factors, what is the first indication of IUGR?

Answer 33

fundal height measuring ≥3cm under expected size for dates in 3rd trimester --> U/S!

Question 34

What are the 4 etiologies of IUGR?

Answer 34

1) aneuploidy: abnormal chromosomes - followed by MFM 2) non-aneuploidy syndromes - followed by MFM 3) viral infections 4) placental insufficiency

Question 35

What are maternal risk factors for IUGR?

Answer 35

1) cardiac, renal disease 2) lives at high altitude 3) chronic malnutrition 4) Celiac disease 5) substance abuse 6) multiple gestation 7) stress 8) autoimmune disease

Question 36

symmetric IUGR

Answer 36

head and body <10th percentile on U/S - occurs early in pregnancy - R/T aneuploidies, viruses - more problematic

Question 37

asymmetric IUGR

Answer 37

head circumference >>> abdominal circumference - occurs after 30 weeks - caused by uteroplacental insufficiency - elevation in placental blood flow resistance --> shunting of fetal blood to upper body and head (brain)

Question 38

What are benign causes of bleeding in the first trimester?

Answer 38

1) implantation spotting 2) cervical polyps 3) vaginal/cervical infection (e.g. GC/CT, HPV) 4) postcoital spotting

Question 39

What are concerning causes of bleeding in the first trimester?

Answer 39

1) spontaneous pregnancy loss | 2) ectopic pregnancy

Question 40

complete abortion

Answer 40

- complete passage of products of conception - closed cervix, small uterus - +/- blood in vaginal vault

Question 41

incomplete pregnancy loss

Answer 41

AKA threatened abortion AKA inevitable abortion - intense cramping - +/- heavy bleeding - partial passage of products of conception - cervix open OR closed

Question 42

delayed pregnancy loss

Answer 42

AKA missed abortion AKA blighted ovum - closed cervix - small or AGA uterus - amenorrhea = only s/sx when FHT not heard

Question 43

septic pregnancy loss

Answer 43

- VERY RARE | - loss accompanied by uterine infection and possible sepsis

Question 44

What is the effect of pregnancy on uterine fibroids?

Answer 44

- pregnancy hormones promote growth | - people w/ fibroids have 2x rate of SAB

Question 45

What medications increase risk of SAB?

Answer 45

1) isotretinoin (accutane) | 2) NSAIDs

Question 46

What are high risk factors for ectopic pregnancy?

Answer 46

1) IUD (Mirena) 2) tubal ligation/other tubal surgery 3) hx of ectopic pregnancy

Question 47

What are moderate risk factors for ectopic pregnancy?

Answer 47

1) infertility 2) ART 3) hx of genital tract infection 4) multiple sex partners 5) smoking 6) African-American

Question 48

What is the effect of pre-eclampsia on placental development?

Answer 48

decreased trophoblastic invasion of decidua --> spiral arteries are less elastic --> increased arterial pressure, lower volume

Question 49

What are fetal risk factors for IUGR?

Answer 49

1) teratogenic exposure 2) fetal infection 3) genetic disorder

Question 50

What are placental risk factors for IUGR?

Answer 50

1) primary placental disease 2) placental abruption and infarction 3) placenta previa 4) placental mosaicism

Question 51

Which patients need RhoGAM?

Answer 51

maternal blood is Rh -

Question 52

How long does one dose of RhoGAM last?

Answer 52

12 weeks - needs to be readministered

Question 53

What is RhoGAM management postpartum?

Answer 53

If baby is Rh +, administer 300g RhoGAM w/in 72h after birth