Preg and lactation Flashcards
what is the Zona Pellucida
the oocyte membrane which the sperm passes through during fertilization
what hormone is involved in transport of the ovum? when does it occur?
Isthmus of the tube remains contracted for first 3 days after ovulation. Progesterone relaxes the smooth muscle allowing entry into the uterus
why is it important that the fallopian tubes remain contracted for the first 3 days after ovulation
it allows for several stages of cell division forming the blastocyte
what does the blastocyst use for nutrition as it travels to implantation
uterine milk
how long is the blastocyst in the uterus before implantation
1-3days
what is the role of the cytotrophoblasts
the inner layer of the trophoblast that attaches the blastocyst to the endmetrium
what is the role of the syncytiotrophoblast
the outertrophoblast layer that makes the nutrient connection to the endometrium
how does the progesterone (released from the corpus luteum) affect the endometrial cells
it causes the endometrial cells to become swollen and filled with glycogen, proteins, and lipids
After implantation Progesterone causes endometrial cells to swell further forming what?
DECIDUAL CELLS (decidua) (allow for nutrition)
what is the chorion
the layer bt placenta and mother formed by tropoblasts
for how long does the embryo obtain nutrient from the decidua by trophoblastic nutrition? where is the nutritional source after this?
up to 8 wks. Then placental diffusion takes over
what do the umbilical arteries do?
carry deoxygenated blood from fetus to placenta
what do the umbilical veins do?
carry oxygenated blood from placenta to fetus
when is blood pumped by the fetal heart
21 days post fertilization
what ratio can be used to assess fetal development
fetal placental weight ratio (1g placenta feeds 7g fetal tissue)
what are the typical vascular contents in the umbilical cord
2 umbilical arteries, 1 umbilical vein
what 4 factors contribute to the oxygen gradient in the placenta
Maternal 50mmHg: fetal 30mmHg
Fetal hemoglobin= inc affinity
Hemoglobin concentration= 50% greater in fetus
Double Bohr Effect- fetal blood alkaline, moms is acidic
how does glu pass through the placenta
facilitated diffusion in the placenta
how do fatty acids pass through the placenta
diffusion
what secretes hCG
tropoblasts
when is hCG detectable in the blood? when does it peak?
in blood 8-9 days post ovulation (just after implantation), peaks 10-12 wks
inc hCG effect?
Maintains corpus luteum beyond normal lifespan
Stimulates production of progesterone and E2: (keeps FSH low to prevent menstruation)
Endometrium forms decidua-like cells.
hCG receptors in endometrium and myometrium and can inhibit contractions produced by oxytocin
Immunosuppressant
when will the corpus luteum degrade if it is stimulated by hCG
Corpus luteum involutes after 13th to 17th week when placenta takes over hormone production.
where is estradiol initially produced (first 5-6wks following implantation)? where is it produced after?
Initially produced by corpus luteum (first 5-6 wks) stimulated by hCG
Then from placenta syncytial trophoblast cells (from DHEA-S from adrenals of fetus and maternal)
what is the maternal/ fetal requirement to properly make estrogen and maintain the uterus
need healthy adrenal glands in both the mother and the fetus
what is the function of estradiol is preg
Proliferative function Enlargement of: -Uterus -Breast tissue and ducts -External genitalia Relax pelvis ligaments (along with relaxin)
how does estradiol affect Sacroiliac joints and
Symphysis pubis
Sacroiliac joints: limber
Symphysis pubis: elastic
what does urine estiol indicate
index of fetal well-being (fetal and maternal adrenals working)
where is progesterone produced in pregnancy
Corpus Luteum followed by placenta production
what do the fetal/maternal adrenal glands use progesterone for
it is the major substrate for cortisol and aldosterone
what is the backbone of estrogen and progesterone
cholesterol
what is progesterones effect in preg
Decreases contractility of uterus: inhibits prostaglandin production and dec sens to oxytocin
Increases secretions of fallopian tubes and uterus
what is the function of Human Chorionic Somatomammotropin (hPL)
Development of breast tissue
Similar to action of growth hormone
-formation of protein tissues
-dec insulin sens in mother
when/where is hPL produced
Secreted by placenta by 5th week of pregnancy
what happens to resting BS levels during preg
they typically inc to allow inc use by the fetus
what are the CO changes during preg
Increase in cardiac output: 30-40% by 27th week then slightly above normal at parturition (less active in 3rd trimester= dec need)
what are the blood volume changes during preg
inc at least 30%
what needs to be monitored in a hypothyroid pt during preg
they may not be able to adapt to the inc in maternal metabolism (need to inc synthroid)
what is the BP changes during preg
BP only slightly increases but they dec close to term bc vasodilation causes dec TPR
why does respiration inc during preg
Progesterone increases respiratory center’s sensitivity to CO2
what is the kidney function change during preg
Estrogen causes vasodilation of afferent aa.= Increase GFR and Increase RBF
There is also inc Na absorption to allow for inc volume
what is the definition of spontaneous abortion
pregnancy loss before 20 weeks of gestation
when do most spontaneous abortions occur by
12wks
what % of clinically recognized preg are spontaneously aborted
10-15%
what is aneuploidy
abn # of chromosomes
what is polyploidy
more than the 2 paired sets of chromosomes
what are maternal causes of spontaneous abortions
Luteal-phase defect Poorly controlled diabetes Other uncorrected endocrine disorders Physical defects of the uterus : Systemic disorders affecting maternal vasculature Bacterial
how can lupus cause spontaneous abortions
can cause antiphospholipid antibody syndrome= hypercoag state
which trimester is ascending infections more common to cause spontaneous abortions
2nd
what is the definition of ectopic pregnancy
Implantation of the fetus in any site other than a normal intrauterine location
where is the most common sites of ectopic preg
Fallopian tubes (∼90%) Ovary Abdominal cavity Intrauterine portion of the fallopian tube (cornual pregnancy)
what inc risk for ectopic preg
- Prior pelvic inflammatory disease resulting in fallopian tube scarring (chronic follicular salpingitis)
- Appendicitis
- Endometriosis
- Previous surgery
- Intrauterine contraceptive devices:
what is the most common cause of hematosalpinx
hematosalpinx(blood-filled fallopian tube) is most commonly caused by tubal pregnancy
when does severe abd pain occur with ectopic preg? what other Sx occur?
6wks from previous normal menstral period. hemorrhagic shock with signs of an acute abdomen
ectopic preg dx
Diagnosis : Chorionic gonadotropin assays, ultrasound studies, and laparoscopy
when can US imply monozygotic twins
only with monoamnionic monochorionic placentas
what occurs when division of monozygotic embryo at day 1-3 p fert
dichorion-diamnion
what occurs when division of monozygotic embryo at day 4-6 p fert
monochorion-diamnion
what occurs when division of monozygotic embryo at day 7-9 p fert
monochorion-monoamnion
what is placenta accreta
Partial or complete absence of decidua with adherence of the placental villous tissue directly to the myometrium and failure of placental separation
what are pridisposing factors for placenta accreta
Placenta previa (60% of cases) History of previous cesarean section
how do accreta, increta, and percreta differ
Accreta: Invasion of myometrium-does not penetrate entire thickness
Increta: Extends into myometrium-penetrating the muscle
Percreta: Penetrates entire myometrium to serosa
how does preeclampsia differ from gestational hypertension
proteinuria with preeclampsia
how does preeclampsia differ from gestational eclampsia
convulsions with eclampsia
what is HELLP syndrome
hemolysis, elevated liver enzymes, low platelets
what plays a role in the pathogenesis of preeclampsia/eclampsia
The exact mechanisms : still being investigated
Placenta plays a central role in the pathogenesis
Symptoms disappear after delivery of the placenta
what are the critical abnormalities in preeclampsia
Diffuse endothelial dysfunction
Vasoconstriction (leading to hypertension)
Increased vascular permeability (proteinuria and edema)
what are the characteristic findings of the placenta in eclampsia
Thrombosis, lack of normal physiologic conversion, fibrinoid necrosis, or intraintimal lipid deposition (acute atherosis)
how is the liver affected from eclampsia
irregular, focal, subcapsular, and intraparenchymal hemorrhages lesions
how are the kidneys affected from eclampsia
Glomerular lesions : diffuse, marked swelling of endothelial cells, the deposition of fibrinogen-derived amorphous dense deposits on the endothelial side of the basement membrane, and mesangial cell hyperplasia
Bilateral renal cortical necrosis : in severe cases
what other organs can have thromboses/hemorrhage from eclampsia
liver, kidney, Brain, heart and the anterior pituitary
what causes the proliferation of placental tissue(either villous or trophoblastic) seen in gestational trophoblastic diseases
Amplification and overexpression of oncogene products: erbB-2 & EGFR
Downregulation of tumor suppressor genes: p53, Rb
what lesions are included in gestational trophoblastic diseases
Hydatidiform mole (complete and partial)
Invasive mole
Choriocarcinoma
Placental-site trophoblastic tumor
what are hydatidiform moles characterized histologically by
cystic swelling of the chorionic villi
variable trophoblastic proliferation
what do hydatidiform moles inc risk for
Associated with an increased risk of persistent trophoblastic disease (invasive mole) or choriocarcinoma
what causes complete moles
Results from fertilization of an egg that has lost its chromosomes, and the genetic material is completely paternally derived
what causes partial moles to form
Partial moles arise from two sperm fertilizing a single ovum
Karyotype is triploid (e.g., 69,XXY) or occasionally tetraploid (92,XXXY)
what type of mole has a risk of causing choriocarcinoma
only complete
why is hCG extremely elevated with hydatidiform moles?
trophoblasts produce hCG
what is the classic gross appearance of hydatidiform mole morphology
delicate, friable mass of thin-walled, translucent, cystic, grapelike structures
how do partial and complete moles differ histologically
Partial mole :
Fetal parts are more commonly present
Some villi are edematous
Trophoblastic proliferation is focal and less marked
Complete mole :
All or most of the villi are enlarged and edematous
Diffuse trophoblast hyperplasia
what is used to differentiate partial from complete moles
p57- which is maternally transcribed but paternally imprinted
what is seen with US with hydatidiform mole
diffuse villous enlargement
how are hydatidiform moles monitored to determine if they become persistent/invasive or choriocarcinomas
serum HCG levels are usually followed until they fall to and remain at zero for 6 months to a year
what is a invasive mole
A mole that penetrates or even perforates the uterine wall
Invasion of the myometrium by hydropic chorionic villi, accompanied by proliferation
what are clinical features of invasive moles
Vaginal bleeding and irregular uterine enlargement
Persistently elevated serum HCG
Varying degrees of luteinization of the ovaries
May result in uterine rupture
how are invasive moles//choriocarcinomas treated
both respond well to chemotherapy
what is necessary if a invasive mole results in uterine rupture
hysterectomy
what are choriocarcinomas
A malignant neoplasm of trophoblastic cells derived from a previously normal or abnormal pregnancy, which can even include extrauterine ectopic pregnancy
choriocarcinoma have a overexpression of what
EGFR
what is the gross morphology of choriocarcinomas
Classically a soft, fleshy, yellow-white tumor
Large pale areas of ischemic necrosis, foci of cystic softening, and extensive hemorrhage
what is the histological morphology of choriocarcinomas
Does not produce chorionic villi
Consists entirely of a mixed proliferation of syncytiotrophoblasts and cytotrophoblasts
Mitoses are abundant
where are choriocarcinoma metastases found
Metastases are found in the lungs, brain, bone marrow, liver, and other organs
what are placental-site trophoblastic tumors (PSTT)
Neoplastic proliferation of extravillous trophoblast
what are the clinical features of PSTT
Uterine mass with
- Abnormal uterine bleeding
- Amenorrhea
- Moderate elevation of β-HCG
