Pregnancy Physiology Lecture Powerpoint Flashcards
Recall the 3 trimesters of pregnancy
0-13 is first
14-28 is second
28-end (typically 40) is third
Most common signs that cause patients to come for a pregnancy eval
missed menstrual period (a week to 2 weeks late)
Gestational age =
Embryonic age (from fertilization) + 2 extra weeks (from the last period)
ASSUME GESTATIONAL AGE UNLESS OTHERWISE INDICATED***
Symptoms 1-2 weeks after fertilization in the mother (5)
- breast tenderness
- nipple sensitivity
- extreme fatigue**
- nausea
- urinary frequency
Pelvic exam uterus sizing
Should be able to correlate uteral enlargement with menstrual dates, if smaller than expected may be ectopic, spontaneous abortion, etc. and if uterus larger than expected may indicate uterine leiomyomata, twin gestation, molar pregnancy
Molar pregnancy
When a nonviable fertilized egg implants in the uterus and will fail to come to term, seen most often in patients under 20 or over 45, causes mass to grow in the uterus that appears as a “snowball” shape on ultrasound and can become cancerous excreting excess, extremely high hCG (extreme nausea and other symptoms)
hCG levels during pregnancy
Detected in serum levels as early as 7-9 days after ovulation, very soon after implantation it begins secreting, being 50-250 mIU/ml by time of first missed period, First 3 to 4 weeks after fertilization should double every 2 days, peaks 60-70 days (100k mIU/mL!) after fertilization then decreases dropping within 4 weeks completely off upon completion/late term abortion, if abnormally low can be due to spontaneous abortion or ectopic pregnancy, if abnormally high can be due to multiple pregnancies or molar pregnancy
hCG function in pregnancy (5)
- Maintain corpus luteum
- stimulate both adrenal and placental steroidogenesis
- stimulate fetal testes to secrete increasing amounts of testosterone to induce internal virilization
- hCG is immunosuppressive and may be involved in materal lymphocyte function
- hCG possesses thyrotrophic activity (see hypothyroidism in mother after birth before returning to rise)
Early pregnancy factor (EFP) test
A product of platelet activation and cell proliferation secreted into circulation from cytoplasm, earliest known marker of fertilization and can be measured to determine if pregnant almost immediately
Even 2 weeks after first semester abortion hCG levels may be…
If it remains at that value even after the allotted time, might be indicative of these 3 pathologies
….very high, with pregnancy tests still reading positive up to 40 days after 1st trimester abortion
- continuing missed intrauterine pregnancy
- retained placental fragment
- ectopic pregnancy
Fetal movement should occur at least at ___ weeks gestation otherwise trouble!
19
At what week can the fetal heart be demonstrated to beat on TRANSVAGINAL ultrasound, how about on low doppler ultrasound?
4-6 weeks post conception or 6-8 gestational
10-12 weeks gestational age
Blighted ovum
Loss of definition of gestational sac or absence of fetus by 7-8 weeks of amenorrhea despite the body still believing it is pregnant for several more weeks before it eventually miscarries resulting in heavier menses as the tissue collapses, can be confirmed by ultrasound to see the empty sac
Hegar sign***
Palpable softening of the lowest part of the uterus at 6 weeks (just above the cervix)***, indicative of probable evidence of pregnancy
McDonald sign***
When the uterine body and cervix can be easily flexed against once another*** indicative of probable evidence of pregnancy
Chadwick sign***
Mucus membranes of vulva, vagina, and cervix becoming congested and having blue hue between 6-8th weeks gestation*** indicative of probable evidence of pregnancy
Goodell sign**
Softening of the cervix by beginning of 2nd month of pregnancy** indicative of probable evidence of pregnancy
Braxton hicks contractions
Not normally felt until 3rd trimester but some women in the 1st trimester, painless and irregular contractions “false labor pains”
Nausea in pregnancy and how is it relieved?
Occurs in 2-12 weeks of pregnancy in approx half of pregnant patients, subsides 6-8 weeks later, rarely persists thru whole pregnancy (hyperemesis gravidarium), rarely occurs after 1st trimester, most severe upon waking and tends to lessen as day progresses, treated with simple things such as food avoidance etc and occasionally a zofran
Linea nigra
Dark lines descending from the umbilicus due to deposits of melanin that falls off upon delivery
Bladder irritability in pregnancy (4)
- early in pregnancy enlarging uterus puts pressure on bladder
- hormonal changes increase urinary frequency
- usually resolves by 2nd trimester
- returns late pregnancy when head descends into pelvis and puts pressure on bladder
Pseudocyesis
Imaginary pregnancy with high progesterone and hCG, most often occurs in women nearing menopause or young who have an unfulfilled desire for pregnancy, will swear they are feeling the baby moving despite no actual fetus has implanted in them
Fetoplacental unit incomplete upon observation of delivery indicates…
….partial retention of part of the placenta, requires immediate removal to prevent bleeding complications
3 layers of adrenal cortex and what they secrete,what does the adrenal medulla secrete?
Zona glomerulosa (aldosterone) Zona fasiculata (cortisol) Zona reticularis (androgens, DHEA - largest portion during developing fetus and stimulated by increased prolactin in fetal pituitary)
Catecholamines (epi and norepi
