Things I don't know: Ob/gyn Flashcards
When and from what to germ cells originate?
4th week of embryonic life
endoderm of yolk sac
When/how do germ cells form primitive gonad?
6th week embryonic life
germ cells migrate to genital ridge and associate with somatic cells
What type of errors occur in older men vs. older women?
men: mitotic errors
women: chromosome errors
How does the number of sperm produced differ from the number of ova?
sperm: many millions, ongoing process after puberty
eggs: 2.5 million at birth (already have all you will make at this point), most degenerate, left with about 400 ova in reproductive years
When do oogonia
- begin meiosis I
- what phase does meiosis I arrest
- when is meiosis I complete
- what phase does meiosis II arrest
- when is meiosis II complete
- month 3 of embryonic development
- prophase: diakinesis stage (as primary oocyte)
- ovulation
- metaphase (as secondary oocyte)
- fertilization
What separates?
Are the products identical or different (ignoring recombination)?
What would be the chromosome result be if nondisjunction occurred and a trisomy child was born?
1. Meiosis I
2. Meiosis II
- homologs; different; all 3 chromosomes are different
- sister chromatids; identical; 2 chromosomes match (look at centromeric DNA that is not involved in crossing over), 1 is different
order of mitosis/meiosis
Prophase
Metaphase
Anaphase
Telophase
leptotene
1st stage prophase
chromosomes have replicated but lie on top of each other
zygotene
2nd stage prophase
homologous pairs move together and pair or synapse
pachytene
3rd stage prophase
first time you can see bivalent chromosome: CHEERLEADER pose
2 homologous chromosomes now look like a tetrad
diplotene
4th stage prophase
CROSSING OVER occurs at CHIASMATA
diakinesis
5th stage prophase
oogenesis is frozen here until ovulation
chiasmata
areas of contact between homologs allowing crossing over
metaphase
nuclear membrane disappears
spindles appear
pairs align on metaphase plate
anaphase
homologs/sister chromatids pulled apart by spindles attached to centromeres
telophase/cytokinesis
cell division
When does nondisjunction occur?
What will be the status of the chromosomes if a trisomy child is born of it?
Meiosis I
all chromosomes are different
Insl-3 (insulin-like substance 3)
produced by gonad
play role in testicular descent
If a child has streak gonads or no SRY gene (regardless if XX or XY), what will they look like?
no AMH: uterus, fallopian tubes
presents at female with no breasts or periods
Common findings in people with mullein duct abnormalities (MDA)
infertility
endometriosis
renal anomalies
When does the uterovaginal septum resorb?
9-12 weeks gestation
unicornate uterus
- uterus
- ovaries
- kidneys
- pregnancy considerations
- development of only one horn of uterus
- two
- ipsilateral (same side) renal anomalies
- pregnancy: normal outcome, preterm labor, malpresentation
uterus didelphys
- uterus
- ovaries
- kidneys
- pregnancy considerations
complete failure of duct fusion
- two: separate uteri, upper vagina (lower may be separated by septum), cervizes
- two
- renal AGENESIS
- normal, preterm
T shaped uterus
DES exposure in utero
risk for clear cell carcinoma of vagina and pregnancy loss
Rokitansky Kunster Hauser syndrome
- uterus
- ovaries
- kidneys
- pregnancy considerations
complete agencies of Mullerian structures
present: amenorrhea
1. NO upper vagina, cervix, uterus or tubes
2. 2 (has breast development)
3. anomalies, skeletal anomalies (bifid vertebra)
4. infertility
Tx: create neovagina
imperforate hymen
failure of reabsorption of uterovaginal septum
presentation: amenorrhea, cyclic pain, abdominal mass
Tx: hymenotomy (sew it open)
Risk factors you wouldn’t think of for ectopic
IVF
endometriosis
Dx and Tx unstable ectopic
Dx: blood in abdomen, acute abdomen, blood loss (tachycardia, hypotension, anemia)
Tx: blood type and laparotomy
Dx and Tx stable ectopic
counsel about rupture
1. quantitative hCG: normally would double in 48 hours
2. progesterone: less than 5 means failed pregnancy
48 hours later
3. curette uterus: products of conception mean SAB; none mean ectopic
Tx: laparoscopy or METHOTREXATE
progesterone less than 5
FAILED pregnancy
ectopic of spontaneous abortion
When is methotrexate appropriate to Tx ectopic? What do you need to do after Tx?
- mass smaller than 5cm
- no cardiac activity
must follow up with hCG to see if it was effective
What is important to advise ectopic patients of?
RECURRENCE
usually other tube is damaged too
discuss contraception, infertility
heterotopic pregnancy
RARE
ectopic and IUP at same time
anovulatory cycle
plenty of estrogen, insufficient progesterone
most common: peripubertal, perimenopausal
Sx: irregular sometimes heavy bleeding
menstrual irregularity peripubertal
REASSURE
no need for exam
Tx: OCs, cyclic progesterone, depo-provera
menstrual irregularity in perimenopausal
likely anovulatory bleeding: reassurance (near menopause), progestin replacement
must RULE OUT CA
string of pearls on ovary US
PCOS
Tx of PCOS
- general
- want regular periods
- decrease unwanted hair
- get pregnant
- LOSE WEIGHT
- OCs
- OCs, dipilatories
- ovulatory agents, metformin
Other causes of irregular bleeding
- pregnant: ALWAYS get pregnancy test
- anorexia
- premature ovarian insufficiency
- hypothyroid
- hyperprolactinemia
- cervical/endometrial CA/polyp
- cervicitis
Tx of irregular bleeding in perimenopausal
- replace hormone: progestin (OCPs, medroxyprogesterone, mirena IUD)
- when medicine fails: endometrial ablation, hysterectomy
Tx of leimyomata
- asymptomatic
- menorrhagia, anemia
- Sx of pressure or infertility and want to preserve fertility
- severe bleeding, pain, child-bearing over
- no Tx
- NSAIDs, hormones
- myomectomy
- hysterectomy
indications that irregular bleeding might be CA
- menometrorrhagia, any post-menopausal bleeding
2. older than 45 (sooner if Hx of anovulatory cycles)
ruling out CA as cause of irregular bleeding
- PAP
- endometrial biopsy: simple hyperplasia give progestins, atypia: hysterectomy
- US
PGF2alpha
elevated in dysmenorrhea
PGE2
elevated in dysmenorrhea
What happens upon infusion of PG to the uterus?
uterine contractions and pain
dysmenorrhea
due to elevated PGs due to fall in progesterone after luteal phase
Tx: NSAIDs, OCs (prevent ovulation and progesterone interactions)
what is the level of PG in women who do not ovulate and have no dysmenorrhea
low
causes of secondary dysmenorrhea
PID
endometriosis
ovarian cysts
Tx: tx cause
Tx of endometriosis
- first
- if no relief
- large endometrioma
- pain/infertility
- mild IVF with difficulties getting pregnant
- OCPs/depo-provera, NSAIDs started 2 days before menses
- laproscopy for Dx: REQUIRES a biopsy
- laparotomy and mass removal; hysterectomy if done child bearing
- laparoscopy to fulgarate lesions with cautery or laser
- IVF
How often do infertile couples present with signs of endometriosis?
30-40%
premenstrual syndrome (PMS)
cause is unclear, Tx Sx
only occurs in OVULATORY women
Sx regularly occur during the same phase of menstrual cycle and regress rest of cycle
Sx: dysmenorrhea, bloat, weight gain, irritable, difficulty concentrating, tired, moody
Dx: menstrual and Sx diary
Tx: NSAID (dysmenorrhea), diuretics (bloat), OCs, reduce salt, SSRI (mood)
Premenstrual dysphoric disorder (PMDD)
extreme PMS: likely an UNDERLYING BEHAVIORAL HEALTH ISSUE that worsens in premenstrual period
PMS Sx plus one of the following: sadness or hopelessness, anxiety or tension, extreme moodiness, marked irritability or anger
Tx: SSRI, OCPs, regular exercise and proper diet, nutritional supplements, avoid stressors
What percentage of pregnancy ends in loss?
When is pregnancy loss more likely to occur?
What percentage is lost after heartbeat is found on US?
25% end in loss; most sporadic
earlier pregnancy is at higher risk
once heartbeat is seen: greater than 90% chance of successful pregnancy
most common cause of sporadic pregnancy loss
most common: chromosomal abnormalities
most common type of chromosome abnormality: aneuploidy: trisomy 16 followed by 21
single most common abnormality: 45,X
causes and Tx of recurrent pregnancy loss
- insufficient cervix; cerclage
- uterine anomalies; Sx
- Ab syndrome; heparin through pregnancy
- parent carrier of balanced translocation; prenatal Dx or PGD
insufficient cervix
cervical integrity compromised
2nd trimester loss, painless bleeding not associated with contractions
Tx: cerclage placed during first trimester (stitch to keep cervix closed)
treat all subsequent pregnancies after first occurrence
Normal pregnancy presentation
- is it normal to bless in 1st trimester
- US: transabdominal
- US: transvaginal
- progesterone level
- hCG level
- 1/4 experience; bleeding with cramping is worrisome
- detect gestations when hCG reaches 2000
- detects gestational sac when hCG is 1000
- progesterone greater than 5
- double every 48 hours
prenatal care
- family Hx questionnaire
- discussion of age, medical, medication and drug risks
- offer screens
- US recommended
- further counseling, referrals, tests if indicated
types of congenital anomalies
- chromosomal: associated with maternal age
- single gene: sickle cell, CF
- structural: sporadic or teratogen associated
When should all women have an US for detection of congenital anomalies?
18-20 weeks
- two things that increase chance of multiple gestations
- other risk factors
- do these apply to monozygotic twinning
- IVF, advanced maternal age
- black, maternal family Hx, young maternal age
- only IVF
complications with twins
- premature: avg. delivery 36 weeks
- birth defects
- c-section needed for some
- maternal DM, hemorrhage
malpresentation
requires c-section
includes presentation of any of these first: breech, face, foot, arm, cord, placenta
Dx of IUGR
cause:
1. symmetrical
2. asymmetrical
serial US: small for gestational age
- chromosomal
- smoking, maternal disease causing placental insufficiency
causes for large for gestational age (LGA)
maternal DM
also: some birth defects (Beckwith-Weideman)
maternal DM effects on fetus
- at risk for at birth
- complications
LGA (glucose moves across placenta: babies become big)
- birth injury: shoulder dystocia
- hypoglycemia, polycythemia, hypocalcemia, hyperbilirubinemia
twin twin transfusion
monochorionic/diamniotic (MONOZYGOTIC)
one twin receives more nutrients and often one dies
recipient twin: struggle more than donor (CHF, polycythemia)
Whose blood is lost
- placenta previa
- vaso previa
- maternal
2. fetal
random facts
- should you do a pelvic exam on someone with 3rd trimester bleeding
- can you diagnose abruptio placenta on US? placenta previa?
- NO: could cause hemorrhage
2. NOT: abruptio placenta, YES placentia previa
Mirena
IUD with levonorgesterol: thickens cervical mucus and prevents implantation
only LOCAL acting steroidal contraceptive
every 5 years
failure rate: 0.2%
benefits: amenorrhea
EXPENSIVE
Cu IUD
every 10 years Cu is a spermacide failure: 0.8% AE: dysmenorrhea, heavy periods CI: Wilson's, Cu allergy MOST EFFECTIVE emergency contraception: prevents implantation (all pregnancies not just implantation)