First Principles and Early Pregnancy - Test 1

Question 1

With regards to the HPG axis, state which hormones act on the various gonadal cell types.

Answer 1

FSH –> Sertoli cells (male) and Granulosa cells (female)

LH –> Leydig (male) and Theca cells (female)

Question 2

Which neurons in the CNS are responsible for mediating the negative feedback of the HPG axis?

Answer 2

Kiss1 neurons release kisspeptin to upregulate GnRH release from the hypothalamus.

Question 3

Where does sperm production occur?

Answer 3

Seminiferous tubules

Question 4

What do Sertoli cells make?

Answer 4

Anti-mullerian hormone (for sex differentiation)

Inhibin (neg. feedback for HPG axis)

Androgen binding protein (ABP) - concentrates testosterone for spermatogenesis

Question 5

Is GnRH secreted constitutively, or in a pulsatile fasion?

Answer 5

Pulsatile bitch

Question 6

Name a GnRH analogue that is used to treat prostate cancer. How does it work?

Answer 6

Leuprolide is a GnRH receptor agonist that downregulates LH and FSH secretion

Question 7

At what cell cycle stage are primary oocytes arrested?

Answer 7

Prophase I

Question 8

At what cell cycle stage are secondary oocytes arrested? When do oocytes complete meiosis?

Answer 8

Metaphase II. Meiosis is completed after fertilization.

Question 9

How early in pregnancy can hCG be detected? When does hCG peak?

Answer 9

Can be detected as early as 7-10 days after fertilization. Peaks at the end of the first trimester.

Question 10

Describe the relative potencies of androgens.

Answer 10

DHT > Testosterone > Androstendione > DHEA

Question 11

Describe the relative potencies of the estrogens.

Answer 11

E2 (17-beta estradiol) > E1 (estrone) > E3 (estriol)

Question 12

Describe the relative potencies of the progestens.

Answer 12

Progesterone > 17-OH-progesterone

Question 13

What is the first, rate-limiting step in sex steroid synthesis?

Answer 13

Cholesterol –> pregnenolone

Question 14

Which hormone has higher affinity for sex hormone binding globulin: 17-b-estradiol (E2) or testosterone?

Answer 14

Testosterone

Question 15

Name two selective estrogen receptor modulator (SERM) drugs, their clinical indications, and side-effects.

Answer 15

Tamoxifen - used for breast cancer; side effects are increased thrombosis risk

Raloxifene - treats osteoporosis; no side effects listed

Question 16

What is the MOA of clomphine, its indications for use, and what are its side effects?

Answer 16

Partial estrogen receptor agonist

Used to induce ovulation and to treat male infertility

No side effects

Question 17

Name a drug that treats vaginal dryness. What is its MOA?

Answer 17

Ospemifene. Partial estrogen receptor agonist at vaginal tissue.

Question 18

Which enzyme converts testosterone –> DHT?

Name a drug that blocks this enzyme and its clinical use.

Answer 18

5-alpha-reductase

Finasteride blocks it to treat BPH, male-pattern baldness, and for male-to-female transexuals

Question 19

At what age does spermatogenesis begin?

Answer 19

Puberty (~13 yo)

Question 20

Anatomically, where does fertilization occur? What cell stage implants into the uterus?

Answer 20

Fertilization happens in the ampulla of the tube. Blastocyst implants.

Question 21

When is fetal blood flow initiated?

Answer 21

A week after implantation (implantation happens 7-10 days after fertilization)

Question 22

Define the following:

1st trimester

2nd trimester

3rd trimester

Preterm

Term

Post-term

Answer 22

1st trimester is 1-13 weeks gestation

2nd trimester is 14-27 weeks gestation

3rd trimester is 28-40 weeks gestation

Preterm is <37 weeks

Term is 37-42 weeks

Post-term is >42 weeks

Question 23

What is the classic period for teratogenicity?

Answer 23

Between 4-10 weeks gestational age

Question 24

What teratogen category are most medications in? What does that mean?

Answer 24

Category C. Means that it can’t be ruled out that the drug is not a teratogen but there is no clear evidence that the drug is harmful to fetal development.

Question 25

What category of teratogenicity is considered to have the highest fetal risk? Name four drugs that fall into this category.

Answer 25

Category X Vaproate Coumadin Methotrexate Accutane

Question 26

What are the TORCHeS infections?

Answer 26

T = Toxo O = Other - Zika - Parvovirus R = Rubella C = CMV H = HSV e nothing S = Syphilis

Question 27

Name the noninvasive newborn screening tests and when each can be performed.

Answer 27

1st trimester: Nuchal translucency US (11-14 weeks) Cell free DNA screening (after 10 weeks) 2nd trimester: Serum and nuchal translucency tests (integrated screen) - 15-21 weeks Anatomic ultrasound (18-22 weeks)

Question 28

What diseases are increased nuchal translucency associated with?

Answer 28

Trisomies 13, 18, 21, and Turner syndrome

Question 29

Name the invasive fetal screening tests and when they can be performed.

Answer 29

Chorionic villous sampling (11-14 weeks) Amniocentesis (after 16 weeks)

Question 30

Describe the expected relative values expected on a quad screen for Trisomies 18, 21, and neural tube defects.

Answer 30

Question 31

What is the DDx for 1st trimester bleeding?

Answer 31

Ectopic pregnancy Threatened or inevitable abortion Molar pregnancy Implantation bleeding Uterine, cervical, or vaginal lesions Subchorionic or placental hemorrhage (+ pyelonephritis in real life)

Question 32

These symptoms are classic for...? Female of reproductive age presents to ED with pelvic pain and vaginal bleeding. Pregnancy test is positive.

Answer 32

Ectopic pregnancy

Question 33

What are the treatments for ectopic pregnancy?

Answer 33

Medical (must be hemodynamically stable, can't have kidney or liver disease, must be reliable for follow-up): methotrexate Surgical: salpingectomy (if in fallopian tube)

Question 34

How do you manage incomplete abortion?

Answer 34

Misoprostol (PGE1) or D&C

Question 35

What are the genetic possibilities or molar pregnancies? What abnormal lab findings might you expect in a patient with a molar pregnancy?

Answer 35

Empty oocyte fertilized by two sperm. Normal haploid oocyte fertilized by two sperm. hCG levels are really high in molar pregnancy.

Question 36

What are the four basic principles of teratogenicity?

Answer 36

1. Time-dependent (4-10 weeks gestation) 2. There is a specific mechanism that causes the abnormal development 3. The teratogen has to have access to the developing tissue 4. Teratogenicity is dose-dependent

Question 37

What four ultrasound findings are suggestive of neural tube defects?

Answer 37

Meningocele/myelomeningocele Anencephaly Lemon sign Banana sign