Lecture 15 recap Flashcards
Decreased blood flow to legs in pregnancy increases risk of what? Why?
DVT; slower blood flow causes clotting
What increases renal blood flow?
Progesterone
Is Naegele’s rule for dating pregnancy accurate?
No; incredibly inaccurate- there are apps for this these days
The _________________is the site of fertilization
Ampulla
[Fertilization]
1) Define capacitation
2) What triggers it?
1) Final maturation of sperm
2) Acidic environment removes glycoproteins
[Fertilization]
1) Sperm binds to what part of the egg?
2) What ion does this increase? What does this lead to?
1) Zona Pellucida
2) Ca2+; acrosomal reaction
(acrosome fuses w. plasma membrane)
1) Following implantation of the blastocyst in the uterine wall, the _______________ forms.
2) What form and fill with blood to eventually develop into this structure?
1) placenta
2) Lacunae [eventually become a placenta]
What 2 tissues of the endometrium develops into the placenta?
Trophoblastic and decidual
[Placenta development]
What layer of the chorion continues to expand? What does this eventually erode, and what does this cause?
Trophoblastic layer; maternal capillary walls, leaking maternal blood to fill the cavities
List 2 hormones made by the placenta and describe when each begins to rise and for how long
1) hCG: human chorionic gonadotropin
-detectable 6-8 days post-fertilization [doubles every 2-3 d until 15 wks]
2) hPL: Human placental lactogen
-rises in wk 3 [until term]
1) What hormone extends life of the corpus luteum?
2) What does this also stimulate?
3) When is this hormone detectible?
4) When does it increase and at what rate?
1) hCG
2) luteal steroidogenesis
3) 6-8 days after fertilization
4) Every 2-3 days until about 15 weeks
1) What hormone is similar to GH and PRL?
2) When does it rise in pregnancy?
3) What does it regulate? By promoting what?
4) What condition can it lead to?
1) hPL
2) During the 3rd week until term
3) Fuel availability by promoting maternal insulin resistance
4) Gestational diabetes
[Placental exchange:]
What does estrogen increase and enhance in both the mother and fetus?
Increases size of uterus and blood flow, enhance fetal organ development, increase breast tissue
1) Progesterone produced by the placenta enters the ____________ circulation.
2) Some gets converted to ____________.
3) What effect does this have?
1) maternal
2) DHEAS
3) Increases water solubility and aids in transportation
Estrogen stimulates the renin-angiotensin system to raise _____________ levels and promote ____________ reabsorption, thus, water _____________.
aldosterone; sodium; retention
What are the only two physiologic factors discussed to decrease during pregnancy?
Peripheral resistance and functional residual capacity
[Maternal Adaptation]:
1) There’s a physiological __[increase/ decrease]__ in systemic BP during pregnancy.
2) This should not to be mistaken for ____________.
1) decrease
2) hypotension
1) What type of compression can potentially explain low BP in pregnancy if pt is experiencing symptoms? When and in what position?
2) Why does it happen?
3) List the chain of events
1) IVC compression; > 20 weeks gestation; supine position
2) Growing uterus is compressing on IVC and/or aorta can threaten perfusion to body and/or placenta
3) Less venous return > less CO > BP falls > dizziness, lightheadedness, headache, presyncope > syncope
During pregnancy, a woman’s blood clots more easily to lessen blood loss during labor and delivery and protect from hemorrhage; how?
Coagulability increases:
1) Increase in clotting factors (7, 8, 9, 10) and fibrinogen.
2) Fibrinolytic activity decreases simultaneously.
1) What two things abt pregnancy alter pulmonary funct.?
2) What sensitivity does the rise in progesterone [in pregnancy] enhance?
2B) What does this increase?
1) Progesterone & the enlarging uterus
2) Brain respiratory center to carbon dioxide
2B) Tidal volume
List what happens to these in pregnancy:
1) Airway tone
2) Minute ventilation
3) PCO2
4) Arterial PO2
5) pH
[all due to progesterone and enlarging uterus]
1) Relaxes; bronchodilation
2) Increases: 30%
3) Decrease
4) Increase
5) Slight respiratory alkalosis
1) As uterus enlarges the diaphragm is elevated by how much?
2) What does this cause?
3) What two vitals does this reduce?
1) 4-5 cm
2) Early closure of smaller airways
3) Functional residual capacity and expiratory reserve volume (FRC & ERV)
Why does constipation occur in pregnancy? Explain
Progesterone = vasodilator
-Decreases transmit time in intestines > colonic relaxation > hard stools > constipation
1) GERD (heartburn) occurs in pregnancy bc of what two factors?
2) What lifestyle changes can help?
3) What severe GI condition can occur in pregnancy?
1) LES (lower esophageal sphincter) relaxation + compression of stomach by gravid uterus = reflux
2) Avoid caffeine, spicy foods, nicotine
-TUMS are safe during pregnancy
3) Gallbladder disease
Endocrine function and maternal metabolism change to support fetal growth by increasing what 4 hormones?
1) PRL
2) Cortisol
3) CRH
4) Insulin
Of the 4 hormones discussed that increase in pregnancy:
1) Which involves breastfeeding?
2) Which is a stimulant for labor?
3) Which maintain blood sugar levels (risk of gestational DM)?
4) Which contributes to fetal lung development?
5) Which cause stretch marks and contr. to insulin resistance?
1) Prolactin; “pro-lactation”
2) Corticotropin releasing hormone (CRH)
3) Insulin
4) Cortisol
5) Cortisol
__________ activates milk ejection; aka the “let down” reflex
Oxytocin
1) Parturition (birth) is on average _________ days+/- 14 days from fertilization
2) What hormone keeps the uterus inactive? What expression is reduced?
3) Is this reduction/ block overridden or not?
1) 270
2) Progesterone; estrogen receptors expression (progesterone block)
3) Fetal growth stimulates more receptors, overriding block
Placental estrogen reaches a peak which prepares uterus and cervix for labor and delivery; this includes:
1) ___________ inserted into gap junctions allow the uterine smooth muscles cells to contract as a single unit
2) Increased concentration of myometrial _____________ receptors; ____________ ultimately initiates labor
3) Local prostaglandins degrade local __________ fibers and also increase responsiveness to ___________.
1) Connexons
2) oxytocin; oxytocin
3) collagen; oxytocin
What ultimately initiates labor?
Oxytocin
Parturition’s positive feedback cycle of oxytocin (pre-delivery):
1) What first triggers this cycle?
2) What happens when uterine contractions become more powerful?
1) Pressure of the fetus against the cervix triggers oxytocin from posterior pituitary
2) More oxytocin is released
Parturition’s positive feedback cycle of oxytocin (post- delivery):
1) What causes the secession of this cycle? Why?
2) What two hormones are gone?
3) What hormone inhibitory effect on prolactin is then withdrawn? What does this do?
1) Baby and placenta are delivered,pressure against cervix ceases
2) Placental estrogen and progesterone
3) Estrogen; initiates lactation
