Early Pregnancy Loss, Ectopic, & Rh Isoimmunization

Question 1

Define trimesters of pregnancy

Answer 1

First trimester = first day of LMP to 13 weeks (+6 days)

Second trimester = 14-27 weeks (+6 days)

Third trimester = 28-42 weeks

Question 2

What is estimated date of confinement (EDC)

Answer 2

40 weeks after FDLMP (First date of last menstrual period)

Question 3

Define parameters for abortion vs. preterm delivery vs. full term delivery

Answer 3

Abortion = <20 wks

Preterm delivery = 20-36 weeks (+6 days)

Full term delivery = 37-42 weeks

Question 4

T/F: up to 40% of women will have some vaginal bleeding during early pregnancy

Answer 4

True — this is likely implantation bleeding

Question 5

hCG is first detected in serum 6-8 days after ovulation. Titers <5 mIU/L is negative. A level of 100 IU/L is reached about the time of expected menstruation, and a UPT can detect titers of 25 mIU/L.

During pregnancy, the level of hCG doubles every 2 days and peaks at 10 weeks at 100,000 IU/L.

What is the “discriminatory level” of hCG?

Answer 5

hCG levels of 1500-2000 mIU/L — level at which you should see gestational sac

Question 6

_____ ____ refers to the presence of hCG 7-10 days after ovulation but in whom menstruation occurs when expected

Answer 6

Biochemical pregnancy

Question 7

80% of SABs occur in the first trimester. What is the most common cause of first trimester SABs?

Answer 7

Chromosomal abnormalities

Question 8

The most common cause of first trimester SAB is chromosome abnormalities. What is the most common single abnormality vs. most common class of abnormalities?

Answer 8

Most common single abnormality is 45 XO Turner’s syndrome

Most common class of abnormalities is Trisomy class — Most common of these is trisomy 16

Question 9

Type of spontaneous abortion in which there is vaginal bleeding and a closed cervix, 25-50% of which result in loss of the pregnancy, and treatment involves expectant management

Answer 9

Threatened SAB

Question 10

Type of SAB in which there is vaginal bleeding and the cervix is partially dilated

Answer 10

Inevitable SAB

Question 11

Type of SAB characterized by vaginal bleeding, cramping lower abd pain with a dilated cervix + passage of some but not all products of conception

Answer 11

Incomplete SAB

[tx is usually suction D and C]

Question 12

Type of SAB in which there is passage of all products of concception with a closed cervix, resolution of pain, bleeding, and pregnancy symptoms; no tx needed

Answer 12

Complete abortion

Question 13

Type of SAB in which fetus has expired and remains in the uterus, usually asymptomatic but coagulation problems may develop

Answer 13

Missed abortion

[check fibrinogen levels weekly until SAB occurs or proceed with suction D and C]

Question 14

Type of SAB characterized by fever, uterine and cervical motion tenderness, purulent discharge, hemorrhage, and rarely renal failure d/t retained products of conception

Answer 14

Septic SAB

[start IV abx, proceed with suction D and C]

Question 15

Type of SAB referred to as anembryonic gestation in which fertilized egg develops a placenta but no embryo [US reveals empty gestational sac]

Answer 15

Blighted ovum

[tx is expectant management, misoprostol, or D and C]

Question 16

Define recurrent abortions

Answer 16

Defined as 3 successive SAB, excluding ectopic and molar pregnancies

Question 17

Possible etiologies of recurrent abortions include general maternal factors, local maternal factors, fetal factors, chromosomal factors, and immunologic factors.

What are some general maternal factors that may lead to recurrent SABs?

Answer 17

Infection (mycoplasma, chlamydia, listeria, or toxoplasma)

Smoking and EtOH

Medical disorders (diabetes, hypothyoid, SLE, ANTIPHOSPHOLIPID AB SYNDROME and other clotting disorders)

Increasing maternal age

Question 18

Possible etiologies of recurrent abortions include general maternal factors, local maternal factors, fetal factors, chromosomal factors, and immunologic factors.

What are some local maternal factors associated with recurrent SABs?

Answer 18

Uterine abnormalities (congenital anomalies, submucosal fibroids, uterine septum, asherman syndrome)

Cervical incompetence

Question 19

Describe cervical incompetence as a potential cause of recurrent SAB, including risk factors and tx

Answer 19

Usually seen with 2nd trimester loss

Presents with “painless dilation” and delivery

Risk factors: uterine anomalies, previous trauma, and hx of colonization

Tx: cervical cerclage

Question 20

Possible etiologies of recurrent abortions include general maternal factors, local maternal factors, fetal factors, chromosomal factors, and immunologic factors.

What is the most common immunologic factor associated with recurrent SABs?

Answer 20

Antiphospholipid Syndrome

[has also been associated with recurrent fetal loss, preeclampsia, venous and arterial thromboembolism and stroke]

Tests include lupus anticoagulant, anticardiolipin abs, and anti-b2-glycoprotein 1 abs

Tx with prophylactic dose of heparin and low dose ASA [may also use lovenox]

Question 21

Leading cause of maternal death in the first trimester

Answer 21

Ectopic pregnancy [usually in ampulla of fallopian tube]

Question 22

Risk factors for ectopic pregnancy

Answer 22

Hx of tubal infection

Previous ectopic

Previous tubal surgery or sterilization

In utero exposure to DES

Pregnancy with concurrent IUD

IVF or ART

Cigarette smoking

Question 23

Classic triad associated with ectopic pregnancy

Answer 23

Prior missed menses

Vaginal bleeding

Lower abd pain

Question 24

Clinical presentation of ectopic pregnancy includes possible ectopic, probable ectopic in symptomatic female, and acutely ruptured ectopic.

Describe the designation “possible ectopic” in terms of symptoms, PE, and US findings

Answer 24

[MOST COMMON clinical presentation]

Sxs: mild nonspecific sxs including abd pain, vaginal spotting or bleeding

PE: uterus soft and normal size; may not feel any adnexal mass

US: thickened endometrial stripe (arias-stella rxn), rarely do you see the ectopic pregnancy

Question 25

Clinical presentation of ectopic pregnancy includes possible ectopic, probable ectopic in symptomatic female, and acutely ruptured ectopic.

Describe the designation “probable ectopic” in terms of symptoms, PE, and US findings

Answer 25

Sxs: lower abd/pelvic pain and vaginal spotting or bleeding

PE: abdominal, adnexal tenderness, and/or cervical motion tenderness

US: variable amounts of fluid in cul de sac; may see ectopic

Question 26

Clinical presentation of ectopic pregnancy includes possible ectopic, probable ectopic in symptomatic female, and acutely ruptured ectopic.

Describe the designation “acutely ruptured ectopic” in terms of symptoms, PE, and US findings

Answer 26

Sxs: severe abdominal pain and dizziness (secondary to intraperitoneal hemorrhage)

PE: distended and acutely tender abdomen, usually cervical motion tenderness, signs of hemodynamic instability (diaphoresis, tachycardia, loss of consciousness)

US: reveals empty uterus with significant amount of free fluid

[surgical emergency!!!]

Question 27

Diagnostic tests for ectopic pregnancy

Answer 27

Quantitative hCG — an inappropriate rise of <53% over 2 days is associated with either an ectopic pregnancy or nonviable IUP

Transvaginal US — would not show IUP

Question 28

Medical management of ectopic pregnancy can be used only in compliant women who are hemodynamically stable with an unruptured ectopic.

What is the medical management used in these cases? What is the MOA and when should hCG levels be checked?

Answer 28

Methotrexate (MTX)

Folic acid antagonist which inhibits DNA synthesis and cell replication

Check hCG levels on day 4 and day 7 [if levels decrease by 15%, continue to follow weekly until negative. If levels plateau or fall slowly, give another dose of MTX. If pt becomes symptomatic or hCG titers increase then proceed with surgery]

Question 29

Absolute vs. relative contraindications to MTX

Answer 29

Absolute: IUP, breastfeeding, overt immunodeficiency, alcoholism, preexisting blood dyscrasia, allergy to MTX, active pulmonary disease, PUD, hepatic/renal/hematologic dysfunction, ruptured ectopic and/or hemodynamically unstable pt, noncompliant pt

Relative: gestational sac >3.5cm, embryonic cardiac motion, hCG levels >6000 mIU/mL

Question 30

When is expectant managment an acceptable tx for ectopic pregnancy?

Answer 30

If the pt is stable and symptoms are spontaneously resolving [up to 80% of ectopics with hCG levels of <1000 mIU/mL will not rupture and will resolve spontaneously]

Still must follow closely with serial hCG testing and give strong ectopic precautions

Question 31

There are several surgical options for the management of ectopic pregnancy. What is the preferred approach for pts who are hemodynamically unstable?

Answer 31

Laparotomy

Question 32

There are several surgical options for the management of ectopic pregnancy. What is the preferred approach for stable pts?

Answer 32

Laparoscopy

Question 33

There are several surgical options for the management of ectopic pregnancy. What is the recommended approach when significant damage to the tube is noted, requiring removal of the entire fallopian tube?

Answer 33

Salpingectomy

Question 34

There are several surgical options for the management of ectopic pregnancy. What is the difference between salpingostomy and salpingectomy?

Answer 34

Salpingostomy — incision is made parallel to the axis of the tube over the site of implantation and incision is left open to heal by secondary intention; most studies reveal salpingostomy results in better long-term tubal function [but there is up to 20% risk of residual trophoblastic tissue]

Salpingotomy — incision is sutured closed

Question 35

There are several surgical options for the management of ectopic pregnancy. After surgery is performed, when should hCG titers be repeated?

Answer 35

3-7 days postop

Question 36

Rhesus isoimmunization is an immunologic disorder that occurs in a pregnant Rh-_____ woman carrying an Rh-_____ fetus

Answer 36

Negative; postive

This results in mother’s immune system producing Abs to the fetal Rh Ag, which can cross placenta and destroy fetal RBCs —> serious hemolytic disease in fetus/newborn (anemia, hydrops fetalis, fetal death)

> 90% of cases of Rh isoimmunization are d/t Abs to D antigens

Question 37

Medication used to prevent maternal production of Abs in the case of rhesus isoimmunization

Answer 37

Prophylactic Rh immune globulin (RhoGAM)

Decreases the availability of the RhD to the maternal immune system; usually given in a single 300 mcg dose which can prevent isoimmunization after an exposure of up to 30 mL of RhD + whole blood or 15 mL of fetal RBCs

Question 38

When is RhoGAM administered?

Answer 38

In a Rh-negative woman: Given at 28 weeks and within 72 hours after delivery of a RhD positive infant

[may be given earlier in the presence of otehr factors that increase chance of fetomaternal hemorrhage — ECV, amniocentesis, CVS, MVA, etc.]

Certain high risk situations (placental abruption, manual removal of placenta, etc.) may result in larger volume of fetomaternal hemorrhage and require more than 1 dose of RhoGAM

Question 39

What is the Kleinhauer-Betke test?

Answer 39

Identifies fetal RBCs in maternal blood; will determine if additional RhoGAM is necessary

Question 40

Every pregnant woman at her first prenatal appt should get an ABO blood group, RhD type, and antibody screen. If tests reveal Rh negative woman whose anti-D antibody titers are positive (RhD sensitized), what are the next steps?

Answer 40

Test father of baby for Ag status; if he is RhD negative, no further workup or tx is necessary because the fetus will be Rh negative

If he is positive homozygous for RhD Ag, all fetuses will be Rh positive. If he is positive heterozygous for RhD, the fetal RhD status needs to be determined (cell-free fetal DNA or amniocentesis)

Question 41

Maternal Rh-antibody titers are used as a screening tool to estimate the severity of fetal hemolysis in Rh disease. What result on these titers requires further evaluation?

Answer 41

Titers > 1:16 require further evaluation including detailed ultrasound to detect hydrops and Doppler studies of the middle cerebral a.

[titers <1:8 usually indicate the fetus is not in serious jeopardy; recheck titers q4w]

Question 42

US findings of fetal hydrops

Answer 42

Ascites
Pleural effusion
Pericardial effusion
Skin or scalp edema
Polyhydramnios

Question 43

Doppler assessment of peak systolic velocity in the fetal middle cerebral artery in cm/sec is th emost valuable tool for detecting fetal _____

Answer 43

Anemia

[should perform this test q1-2 weeks from 18-35 weeks; fetal MCA value peak systolic velocity >1.5 MOM for gestational age is predictive of moderate to severe fetal anemia — need to proceed with percutaneous umbilical blood sampling to assess true hemoglobin concentration]

Question 44

Management of severe fetal anemia

Answer 44

Intrauterine transfusions (usually performed between 18-35 wks) using fresh group O Rh-negative PRBCs