OBGYN - Review
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OBGYN Review
*2-3 question per hour
Putting the Guy Back in Gynecology
*2-3 very easy questions
- Semmelweis: figured out hand washing would prevent disease.
- Liability:
- Failure to dx breast ca is number 1 lawsuit (lots of docs involved)
- Bad baby is #2 lawsuit
Early Pregnancy Loss
*1 scenario with 3-4 related quesetions
- Pregnancy test is the first test one runs for any Gyn complaint in a fertile woman.
- Know the definitions of the abortions:
- Abortion is any loss before 20 weeks gestation
- For Threatened Abortions, 25% bleed in second trimester.
- "Septic abortion" is any sort of abortion (regardless of type) that includes maternal infection.
- 70% of spontaneous abortions are because of ch abnormalities.
- Trisomies are mosst common
- Tx of abortions:
- Threatened abortions should be given "expectant management", pelvic rest, and reassurance.
- Inevitable abortions and Incomplete abortions should be treated with dilation / curettage, methergine, and anti-Rh (Rhogam).
- Recall that methergine constricts blood vessels and induces smooth muscle contraction so it can be used to decrease bleeding and to induce labor (as in an incomplete abortion).
- 98% of all ectopic pregnancies are in the fallopian tubes.
- Etiology of ectopic pregnancies is not important for the exam.
*Early pregnancy loss example questions:
Family Planning
*3 basic questions
- There is an 85% chance of getting pregnant with regular intercourse and absolutely no protection.
- Know the contraindications to CHC (combined hormone contraception):
- DVT (deep vein thrombosis), prolonged immobility
- Smoking over the age of 35
- Hypercoagulatory state (like Leiden mutation)
- Poorly controlled HTN
- IUD, IUC, IUS:
- Know the indicators, contraindications:
- Contraindications for IUD:
- Pregnancy
- Unexplained vaginal bleeding
- Uterine infection
- Pelvic tuberculosis
- Uterine architecture abnormalities (fibroids, septum)
- Indicators for IUD:
- contraception sample?
- Cervical cancer is not an hereditary disease but a lifestyle disease (HPV).
- IUD is an inappropriate form of birth control when the pt has an history of STI because IUDs induce peritonitis and endometriitis upon infection.
Maternal Fetal Phys
*3 questions / case presenations focused on GI, Heme, and Pulmonary physiology
- GI:
- In the first trimester, progesterone causes nause / vomitting by slowing smooth muscle.
- Average weight gain over the course of pregnancy is 20 pounds.
- It is not uncommon for mom to lose weight before gaining weight.
- Heme:
- Physiologic anemia occurs in mom because plasma is increased by 50% but RBC count is only increased by 30% (more fluid increased compared to RBC increase).
- Hb in pregnancy is often around 11.5 mg / dL (whereas normal is 12.0-16.0).
- Respiratory:
- In pregnancy, it is normal to be in a state of respiratory alkalosis with metabolic compensation.
Fill this out a bit.
- Relative hyperventilation occurs in pregnancy so as to blow off CO2.
- pO2 is elevated in pregnancy (106-108, compared to normal 70-100).
*Questions
Pregnancy Gone Wrong
*3 cases; 2 focus on management, 1 focuses on diagnosis *Pre-elampsia, placenta previa, and placental abruption
- Definitions important to pregnancy gone wrong:
- Chornic htn is before 20 weeks gestation and after 12 weeks post-partum.
- Pre-eclampsia: BP issues occurring after 20 weeks gestation concurrent with 300 mg proteinuria.
- Eclampsia:
- Definition of Eclampsia:
- having one or more generalized convulsions and / or coma in the setting of preeclampsia
- in the absence of other neurologic conditions
- Treatment for eclampsia:
- Stabilize mom (before delivering), ABCs
- Rx: magnesium sulfate,
- Rx: hypertensions in the severe malignant range (could stroke out)
- Deliver baby once stable (vag, induce, c/s, depending on condition of mom / baby)
- Definition of Eclampsia:
- Placental abruption:
- Placental abruption is a separation of the placenta from the uterine wall.
- Placental abruption presents with abdominal pain and non-reassuring fetal heart rate.
- Placental abruption is poorly diagnosed with ultrasound.
- A history of trauma should always increase one's suspicion of placental abruption.
- Other causes of placental abruption include cocaine, smoking, fibroids.
- Placenta previa
- Placenta previa is the attachment of the placenta near or over the cervical os.
- Placenta previa's described as "low" indicates the placenta has attached low in the uterus, near the os.
- Vaso previa is when major placental vessels lie between the fetus and the os.
- Treatement for Placenta Previa:
- Conservative management, monitor mother and baby.
- With bad heart tones or bleeding after 34 weeks, deliver the baby.
- Even a partial placental previa is an indicator for c-section.
- Placenta previa is the attachment of the placenta near or over the cervical os.
Normal and Abnormal Labor
*3 questions; focused on placenta accreta, pelvimetry
- Pelvimetry:
- The Diagonal Conjugate is an indirect measurement of the Obstetric (True) Conjugate.
- The diagonal conjugate should be 11.5 cm or greater.
- The obstetric conjugate is 1.5-2 cm less than the diagonal conjugate.
- Good conjugates are: diagonal (>11.5), obstetric (>9.5)
- The average fetal head is about 10 cm in diameter.
- Proper pelvimetry exam includes:
- Palpation of the ischeal spines.
- Determination of the pelvic wall shape: convergent or divergent.
- Determination of the bituberous diameter: 6-8cm is ideal
- Determination of the pubic arch angle: >=90 degrees
- If all metrics are adequate, assume a vaginal delivery without difficulty.
- Even if the diagonal is slightly small (slightly <11.5), try a vaginal delivery.
- Ischeal spines are not usually contraindicators of vag delivery.
- Fetal monitoring:
- Baseline heart rate should be 120-160 beats per minute.
- Variability of the heart rate should be seen!
- Accelerations are good!
- Some decels are normal: "early" decelerations during contractions.
- More on decelerations:
- Early and late decelerations generally present as smooth curves.
- Early decelerations occur with uterine contractions (dip with contraction) and represent vagal (head) compression.
- Late decelerations peak after the contraction has begun and indicate fetal hypoxia (poor fetal reserve)
- For late decelerations, delivery qucikly if not near to vag delivery.
- Variable decelerations are sharp changes that can occur any time and represent cord compression.
- Variable decelerations are not usually worrisome unless deep (very low heart rate) or long in duration.
- Cesarean Sections:
- C/s increases the risk of uterine rupture upon subsequent pregnancies.
- C/s increases the risk of placenta previa.
- C/s increases the risk of placenta previa converting to accreta (when the placenta--and maybe even fetus--invade the myometrium).
- This risk increases with each subsequent c/s: 0 (5%), 1 (24%), 2 (48%), 3 (67%), etc.
- In accreta, the nitty box layer is dsyfunctional such that the placenta can't attach and may grow into the myometrium and even into the bladder.
- Accreta is also seen after uterine rupture.
*question:
Embryology
*3 questions; 1 focuses on the type of anomaly, 1 on incidence of congenital anomalies
- Definitions:
- Malformations are abnormalities that result from intrinsically abnormal development processes that have been wrong from the beginning.
- Disruptions are abnormalities that interferes with previously normal development.
- Disruptions include teratogens and amniotic bands.
- Deformations are abnormaliteis of form or shape because of mechanical disturbance.
- Deformities include oligohydraminos (low amniotic fluid levels) which results in a smushed face (like wearing a pair of lady's hose over one's head).
- Dysplasias are abnormal cellular formations.
- Dysplasias include renal issues due to obstruction of flow.
- Single minor anomalies are very common: 14% of live births have a minor anomaly.
- Single major anomalies are not uncommon: 3% of live births have a major anomaly.
- Teratology:
- The first two weeks of gestation is the "all or nothing" stage in which teratogen exposure results in fetal abortion (nothing).
- In this all or nothing period, the teratogen is interfering with implantation and cleavage.
- The first two weeks of gestation is the "all or nothing" stage in which teratogen exposure results in fetal abortion (nothing).
- 75% of all pregnancies are aborted.
*questions:
Abnormal Uterine Bleeding
*3 questions, AUB
- Know the uterine / ovarian cycle!
- Leading up to ovulation is the follicular phase (estrogen dominated) of the ovarian cycle and the proliferative phase of the uterine cycle.
- Post-ovulation is the luteal phase (progesterone dominated) of the ovarian cycle and the secretory phase of the uterine phase.
- Abnormal uterine bleeding:
- Anovulation is the most common cause of abnormal uterine bleeding.
- When a woman doesn't ovulate, there is no corpus luteum and therefore no progesterone.
- Recall that progesterone causes the endometrium to become secretory.
- Without ovulation / progesterone, the endometrium just keeps proliferating.
- Initially, there will be a lack of bleeding as the endometrium doesn't get the progesterone signal drop that causes menses.
- Once the excessively-proliferating endometrium outgrows its blood supply, it will bleed--heavily.
- Terminology:
- Menorrhagia means heavy, prolonged bleeding.
- Metorrhagia means light, irregular bleeding.
- Menotorrhagia means heavy, irregular bleeding.
- Amenorrhea is defined as absent bleeding for 3 or more cycles.
- Eumeorrhea has a cycle of 21-35 days.
- Oligomenorrhea is an interval over 35 days.
- Polymenorrhea is an interval less than 24 days.
- Intermenstrual bleeding is bleeding between regular menses.
- Prementstrual spotting refers to light bleeding just before menses begins.
- Post-coital spotting refers to bleeding within 24 hours of vaginal intercourse.
- Intermenstrual cycle bleeding (bleeding between menses):
- Causes of intermenstrual bleeding include mechanical issues or ovulation.
- polyps, cervical cancer, IUD issues, and infection.
- drop in estrogen just before ovulation
- Causes of intermenstrual bleeding include mechanical issues or ovulation.
- Menorrhagia (regular, heavy):
- Causes of menorrhagia include anatomical issues and coagulation issues.
- fibrionids, polyps
- vWf deficiency
- Causes of menorrhagia include anatomical issues and coagulation issues.
- Menotorrhagia (irregular, heavy):
- Causes of menotorrhagia are anovulatory
- PCOS, thyroid deficiency
- Etiology of abnormal uterine bleeding includes:
- Hormonal: anovulation
- Anatomical: coagulopathies
*questions: **atrophic vaginitis
Menopause and Hormone Replacement Therapy
*3 questions; 1 clinical scenario, sx w/ menopause, menopause workup
- FSH is increased when menopausal
- No end organ means no estrogen to feed back on hypothal to inhibit fsh release.
- Checking estrogen doesn't help
- Declining fertility in menopause is not absolute.
- One can still get pregnant after the onset of menopause.
- Be sure to talk to menopause pts about birth control.
- Contraindications to estrogen replacement therapy include:
- Undiagnosised abnormal genital bleeding
- Cctive thrombosis
- Pregnancy
- Endometrial cancer and breast cancer
- Evaluation of the post-menopausal pt:
- Determine the menopausal stage.
- Determine the diagnsis
- Do a mammogram
- Be sure to rule out pregnancy!
- S&S of Menopause
- Loss of concentration
- Loss of libido
- Decreased vaginal lubrication
- Depression
**blue slide: don't worry about it
*questions
- endometrial cancer suspicion
- all the rest are not contraindications
- loss of concentration is a s/e of menopause
- others are: decrease libido, decreased vag lubrication, depression
Infertility
*3 questions that center on evaluation and diagnositics for infertility
- The definition of infertility is 1 year of regular coitus without conception.
- Infertility can be the result of a single factor or several factors.
- Therefore, we work up from easiest / most-likely / cheapest / least invasive.
- A careful history and physical exam is important for narrowing the tests to be ordered
- Normal fertility requirements
- Regular ovulation
- Patent fillopian tubes
- Receptive endometrium, with hormone cascasde
- Cervical mucus in a favorable state
- Spermatogenesis
- Erectile and ejaculatory competence
- Anovulation associated with ovarian failure:
- Most of the details of ovarian failure are in excess.
- Turner syndrome is one cause of ovarian failure.
- Turner syndrome is characterized by primary amenorrhea, ovarian streaks, no secondary sexual characteristics (because of primary gonadal failure).
- Primary gonadotropic deficiency is another cause of ovarian failure.
- No GnRH / LH / FSH;
- Hypogonadic
- Anosmia
- Functional chronic anovulation:
- Commonly seen in athletes, anorexics, high stress situations, and physical-appearance-success coupling.
- Stress suppresses gonadotropic release at hypothalamus.
- This response to stress is good for a state of famine (don't make more eaters when there's little eating to be done).
- Part of the problem in functional chronic anovulation is that a certain amount of body fat needed to maintain LH / FSH levels and these women lack that fat threshold.
- Polycystic ovarian disease:
- POCD is the most common cause of anovulation.
- POCD presents as hirsuitism, high BMI, oligo- / a-menorrhea, and insulin resistance.
- Workup for the anavulating patient:
- Chemistries: FSH, LH, prolactin
- Recall that prolactinemia / prolactinomas can cause anovulation
- Imaging:
- CT of the sela tercica to identify a prolacitnoma
- U/S of ovaries to be sure they exist and do not have cysts
- Chemistries: FSH, LH, prolactin
Gynecological Cancers
*3 questions; 1 on risk factors of endometrial cancer, 1 on diagnosis, 1 on appropriate tx for pelvic mass
- Endometrial cancer
- Risk factors: age, null-gravis, unopposed hormone replacement, obesity, hypertension, and diabetes.
- Presentation of endometrial cancer includes abnormal bledding, post-menopausal bleeding, pre-menopausal bleeding.
- Uterine cancer:
- For all gynecological problems, consider a pregnancy test as the first diagnostic.
- Upon suspecting uterine cancer, take a biopsy.
- Biopsy is via pipelle.
- Biopsies have a 98% sensitivity for uterine cancer.
- For diagnosing uterine cancer, histeroscopy is the gold standard.
- Hysteroscopy can reveal cancer lesion for direct biopsy.
- Hysteroscopy should not be used for known uterine cancer cases as the fluid used can push malignant cells to new locations
- Suspicion of a uterine cancer can also indicate an U/S.
- The endometrium in non-malignant cases should be less than 6mm thick.
- Endometrium over 6mm is an indication for biopsy.
- Cervical Cancer Epidemiology:
- Cervical cancer screening:
- Screening is now recommended to begin at 21 yo--not based on time of first coitus.
- Pap smears should be done every 1-2 years until 70yo or until a total hysterectomy is performed.
- Pap smears catch most cervical cancer cases: 60% are caught in stage 1.
- Cervical cancer risk factors: minorities / underserved, multiparity, early parity, early coitus
- HPV strains 16, 18, 31, 33 are associated with cervical cancer.
- Some cases of HPV infection (especially in the young, with their highly proliferative cervical epithelium) resolve spontaneously.
- Cervical cancer screening:
*no stats
- Adnexal masses:
- Good prognostic indicators of adnexal masses: being asymptomatic, cystic nature (fluid filled, means it is benign), being young (15-45 yo)
- Bad prognostic indicators of adnexal masses: having associated pain, solid / complex nature, ascites, omental caking quality, lymphadenopathy
**The differential diagnosis for an adnexal mass should include:
- Adnexal mass workup:
- Pelvic exam
- CA 125 as triage, be ready to call in gyncological oncology as backup
- Imaging
- U/S is superior to CT
- Adnexal mass Treatment:
- Operate on large masses.
- Operate on masses with many bad indicators (old age, ascites, etc.)
- Adnexal mass workup:
*questions: