Gynecology Flashcards
Which medications can be used for pregnancy termination?
- Methotrexate
- Misoprostol
- Mifepristone
Mifepristone and Misoprostol together increase pregnancy termination success during first trimester.
What is the mechanism of action of Mifepristone?
- Progesterone antagonist that binds the progesterone receptors with greater affinity than natural hormone.
- Results in apoptosis and necrosis of the uterine decidua preventing further development of first trimester pregnancy.
What is the mechanism of action of Misoprostol?
- Prostaglandin E1 analog
- Causes cervical softening and uterine contractions leading to expulsion of the pregnancy
What is the action of progesterone in pregnancy?
It is secreted by the corpus luteum during the second half of the menstrual cycle to develop the endometrium for implantation.
It is then produced by the placenta for maintenance of pregnancy.
Why does a long term decrease in progesterone lead to a higher risk of endometrial carcinoma?
Because progesterone has inhibitory effects on the endometrium, it counters estrogen-driven proliferation, thereby a decrease in progesterone leads to risk of endometrial hyperplasia and adenocarcinoma.
Polycystic ovarian syndrome diagnosis
Two of the following:
- Hyperandrogenism
- Irregular periods
- Polycystic ovaries on ultrasound
What does PCOS result from?
Increased activity of:
17alpha-hydroxylase
17, 20 lyase
3beta-hydroxysteroid dehydrogenase
Patient with anemia, thrombocytopenia, neutropenia, reticulocytopenia, normal cell lines on peripheral smear and no splenomegaly, most likely diagnosis?
Aplastic anemia
Most common causes of aplastic anemia?
- Viruses (Parvovirus B19, Epstein-Barr)
- Autoimmune
- Drugs (carbamazepine, chloramphenicol, sulfonamides)
What does bone marrow biopsy show in aplastic anemia?
Hypocellular marrow composed mainly of fat and stromal cells
Name a few causes of pancytopenia without splenomegaly?
Severe B12 and folic acid deficiency
Acute leukemia’s
Myelodysplastic syndrome
Aplastic anemia
Which diseases would result in a bone marrow biopsy with hypercellular marrow with increased blasts?
- Myelofibrosis
- Chronic Myelogenous Leukemia
- Myelodysplastic syndrome
AML
What do you see in myelofibrosis?
Anemia Bone marrow fibrosis Extra medullary hematopoiesis Leukoerythroblastosis and tear drop cells in peripheral smear Hepatosplenomegaly
Who is at increased risk for Endometriosis? Who is not
Increased risk: - Nulliparity - Early menarche - Prolonged menses Decreased risk - Multiparity - Extended lactation - Late menarchy
What is endometriosis?
- Presence of endometrial tissue outside the uterus
- Bleeding and shedding of extrauterine endometrium leads to formation of blood collections
- Blood collections eventually undergo hemolysis and inflammation leading to adhesions distorting organ function and structure
What are the adverse effects of endometriosis?
- Adhesions in the fallopian tubes may interfere with ovulation and tube function.
- Adhesions in the uterosacral ligaments may result in fixed retroverted uterus
- Infiltration in the cul-de-sac may cause painful intercourse and tenderness with palpation of the posterior vaginal fornix.
- Dysmenorrhea (painful menses) results with shedding of the ectopic tissue.
Mechanism of action of Selective Estrogen Receptor Modulators?
- Competitive inhibitors of estrogen receptor binding and block ER+ cell growth in breast tissue
- Have a mixed agonist/antagonist action
What are the adverse effects of Selective Estrogen Receptor Modulators?
- Hot flushes
- Venous thromboembolism
- Endometrial hyperplasia and carcinoma (tamoxifen only)
- Increased risk of stroke
- Osteopenia and eventual increased risk of Osteoporosis
- Increased triglycerides
What are Selective Estrogen Receptor Modulators indicated for?
- Prevention of breast cancer in high risk patients
- Tamoxifen is adjuvant treatment of breast cancer in premenopausal women, also for fibroadenomas and cystic changes.
- Raloxifene is for postmenopausal osteoporosis
What molecular changes occur right before labor in myometrium?
- Estrogen stimulates upregulation of gap junctions between myometrial smooth muscle cells
- Increase in gap junction density at delivery heightens myometrial excitability
- Gap junctions consist of aggregated connexin-43 proteins that allow passage of ions between myometrial cells.
- Estrogen also increases expression of uterotonic oxytocin receptors which mediate calcium transport through ligand activated calcium channels.
- Combination of gap junctions and uterotonic receptors results in coordinated synchronous labor contractions
What are the 4 stages of the follicular phase of the menses cycle?
- Begins with primary follicle
- Turns into secondary follicle
- Becomes vesicular follicle
- Then ends when ovulation starts
What hormones predominate in the follicular phase?
- FSH stimulates cycle
- Then estrogen rises and peaks
- Leads to LH peak which leads to ovulation
What are the 4 stages of the luteal phase?
- Starts with ovulation
- Progresses to corpus luteum
- Regression if it is not fertalized
- Corpus albicans is final stage
What hormones predominate in the luteal phase?
- Progesterone predominates most of the phase
- Estrogen remains constant
- LH and FSH are minimal
