Pregnancy Complications Flashcards
What is the critical role, and secondary endocrine roles of the placenta?
critical role in production of progesterone
produces steroid hormones from maternal and fetal adrenal glands, participates in signal pathways for labor, produces peptide hormones that support fetal growth and is important for fetal nutrition, gas exchange and excretion
What peptide hormones does the placenta produce?
hPL: human placental lactogen - increases maternal lipolysis, resulting FFAs to be used for energy production so fetus can use glucose, amino acids, and ketones
hPGL:human placental growth hormone, promotes fetal growth
What important enzyme required for steroidogenesis is not present in the placenta?
placenta lacks 17 hydroxylase
consequently the placenta can only make progesterone and requires DHEA sulfate from the maternal or fetal adrenal glands to make testosterone or androsteinedione
pregnenolone production in the placenta also requires cholesterol from the maternal blood stream
Which form of estrogen is only produced in the placenta?
estriol
When does the luteo-placental shift occur?
up to 7 weeks the corpus luteum is the primary source of progesterone (hCG), after 10 weeks the placenta is the major producer of progesterone
(between 7 and 10 weeks occurs the luteo-placental shift)
Why is progesterone so important in pregnancy, specifically considering its effects on the uterus.
inhibits contractions
decreases vascular resistance
assists in immune adaption
Describe the homologous structure of hCG and where it is produced.
B hCG has an a subunit at is identical to FSH, LH, TSH and a B unit that is unique (long acting qualities derived from unique structure)
it is a glycoprotein that is produced in synctiotrophoblast of the placenta - outer layer of multinucleated cells
Contrast serum v. urine tests of B hCG levels, when is each most useful?
urine test are mostly qualitative, dx. of pregnancy (sensitive to levels 25-50mIU/mL)
serum tests are more qualitative and can be used more to follow pregnancy/ pregnancy complications (sensitive down to 3mIU/mL)
How would you expect BhCG levels to change throughout early pregnancy?
bhCG doubles every 2-3 days in a normal pregnancy until beginning to level off 7 weeks into the pregnancy
High and low levels of B hCG may be support investigation for what pregnancy complications?
high levels:
multiple gestation
molar pregnancy
[hyperemesis gravidarum (morning sickness)]
low levels:
spontaneous abortion
ectopic pregnancy
if a patients B hCG level is more than 1000-1500, signifies that a visible pregnancy should be visible in a normal pregnancy (discriminatory zone)
What is the d/dx for a pregnant woman presenting with vaginal bleeding, cramping and pelvic pain regarding possible early pregnancy complications?
spontaneous miscarriage
ectopic pregnancy
hydatidiform mole
What present of pregnancies result in live births?
63%,
20% end in elective abortion, 17% end in spontaneous abortion
Define spontaneous abortion and give the most common casues.
spontaneous abortion is a pregnancy failure or loss prior to 20 weeks gestation
most commonly due to chromosomal abnormalities, trisomy being the most common, Turner’s being the most common single abnormality
Describe the differentiating qualities of the following types of spontaneous abortions: threatened inevitable missed complete incomplete anembryonic
threatened- fetus with heart rate and close cervix
inevitable- fetus with heart rate and OPEN cervix
missed- fetus WITHOUT heart rate, +/- open cervix
complete- fetus ABSENT and cervix, long or closed
incomplete - some PRODUCTS of CONCEPTION present, cervix OPEN
anembryonic- only GESTATIONAL SAC present, cervix long or closed
When should a gestational sac be visible on pelvic ultrasound?
usually by 5 weeks after LMP or when bHCG is >1000-1,500
embryo normally has cardiac activity by 6-6.5 weeks