Implantation Flashcards
List the stages/time following ovulation to implantation of a fertilized ovum.
Ovulation Fertilization (24 hrs post ovulation) Morula (3 days post fertilization) Blastocyst (5 days) Implantation (6 days)
Progesterone and to a lesser extent estrogen are important for directing what processes of the uterus following fertilization?
Decidualization of endometrial stroma
What cell gives rise to the placenta?
Trophoblast
What hormone produced by trophoblasts maintains the corpus luteum?
hCG
What hormone is hCG similar in structure to?
LH
TSH
FSH
What are the stages of implantation?
Apposition- blastocyst contacts endometrium
Adhesion- penetration of trophectoderm into the endometrium
Invasion- blastocyst completely implants and uterine decidualization becomes pronounced
What 2 cell types are derived from the throphoblasts?
Syncytiotrophoblast
Cytotrophoblast
What is placenta previa?
Implantation occurs near internal cervical os
Define placenta accreta/increta/percreta.
Placenta accreta- placenta attaches to myometrium without penetrating it (most commmon)
Placenta increta- placenta penetrates into myometrium
Placenta percreta- placenta penetrates through myometrium
Which is more common, placenta accreta/increta/percreta?
Placenta accreta
What complication is associated with placenta accreta?
Post partum hemorrhage
What is the most common site of ectopic implantation?
Ampulla of fallopian tube
At what value of the serum pregnancy test can an intrauterine pregnancy be ruled out?
hCG- 1500
Don’t see intrauterine pregnancy, must consider ectopic pregnancy
Does maternal IgM cross the placenta?
No
What are common causes of oligohydramnios?
Rupture of membranes
Congenital anomalies
Nephrotoxic drugs (ACE inhibitors, NSAIDs)
Poor placental perfustion
