1st trimester complications Flashcards
fertilization and implantation
oocyte is swept into lumen of the fallopian tube by the fimbria, fertilization occurs in the ampullary portion of the tube, the blastocyst reaches the uterine cavity by day 4-5
After hatching from the zona pellucida, blastocyst implantation begins day 5-7
with implantation the syncytiotrophoblasts begin secreting hCG, implantation is complete by day 9-10
hCG measurment and function
Synthesized by villous sycytiotrophoblast- detectable 7-10 days after fertilization
hCG takes the place of LH (luteinizing hormone) and rescues the corpus luteum, corpus luteum secretes progesterone and estrogen until placental steroidogenesis is established
hcg rule of 10s
hCG levels rapidly increase in a curvilinear fashion in early pregnancy (roughly doubles every 48 hours)
100miU/mL at time of missed menses (4 weeks post LMP)
peaks at 100000 at 10 weeks post LMP
10000 miIML at time of delivery- 40 weeks
hCG and LH
hCG and LH bind to the same receptor, (LHCGR), because of its similarity to LH, hCG is used clinically to induce ovulation in the female ovary during fertility treatment as well as stimulate testosteron production in the male testes
Causes of bleeding in early pregnancy
viable pregnancy physiologic bleeding from implantation, subchorionic hematoma
Non viable pregnancy
Ectopic pregnancy
Gestational trophoblast disease or hydatidiform mole
polyp, trauma, infection
spontaneous abortion/miscarriage/ pregnancy loss
embryonic fetal loss before 20 weeks calculated from last menstrual period
Occurs in approximately 10-15 of clinically recognized pregnancies, risk increases with age
Most common cause is embryonic/fetal chromosomal
missed abortion
embryonic/ fetal loss/ demise <20 weeks without any passage of fetal or placental tissue
Anembryonic early pregnancy loss- gestational sac without corresponding embryo identified on ultrasound, definitive diagnosis if MSD>25 mm
Embryonic early preganancy loss- embryonic pole visible on ultrasound no cardiac activity
recurrent pregnancy loss
3 or more spontaneous pregnancy before 20 weeks, occurs in less than 1% of couples attempting to have childrenm after evaluation etiology unexplained
Anatomic- uterine anomalies (septate uterus) fibroids, intrauterine adhesions
Endocrine- Diabetes, thyroid dysfunction, PCOs
Genetic- translocations or aneuploidy
Immuno- anti phospholipid antibody syndrome, SLE (LUPUS),
Environmental- smoking toxins meds, infection
classic clinical triad of ectopic pregancy
Abdominal and or pelvic pain, amenorrhea and abnormal vaginal bleeding, positive pregnancy test
Ectopic pregnancy
Blastocyst implants outside of the endometrial cavity, 2% of all pregnancies, 90% are located in the fallopian tube and the remainder in a cervical, ovarian, interstitial hysterctomy scar or abdominal location
a heterotropic pregnancy is defined as a coexisting intrauterine and extrauterine pregnancy
Gestational Trophoblastic disease (GTD)
A group of rare diagnoses that all arise from abnormal proliferation of trophoblastic tissue, the benign form is a hydatidiform mole, malignant forms are grouped as gestational trophoblastic neoplasia (persisitent) or invasive GTD, choriocarcinoma, and placental site trophoblastic disease
ALL form of GTD are associated with elevated levels of human chorionic gonadotropin (hCG)
Complete molar pregnancy
diffuse trophoblastic proliferation and hydropic grape like chorionic villi
Classic snowstorm or bunch of grapes appearane on ultrasound
Results from fertilization of an ENUCLEATE egg
Paternally derived diploid genotype 46 XX or 46XY
Without maternal DNA no fetal structures are able to develop
can lead to persistent GTD or malignancy
Partial molar pregnancy
a partial mole contains fetal tissue, amniotic fluid, and focal trophoblastic hyperplasia and focal hydropic chorionic villi
Arises from fertilization of a haploid ovum by two sperm or by a single sperm that then duplicates
one set of maternal and 2 sets of paternal
69 XXy or 69 XXX
treatment is D and C and monitor hCG, chemo and methotrexate
lower risk of GTD or malignancy
methotrexate
An anti metabolite chemotherapeutic agen that binds to the enzyme DHFR and acts as a competitive antagonist to DHFR
Interference in DNA synthesis and disruption of cell replication
Its used to treat rapidly dividing trophoblastic tissue and is used in the treatment of ectopic pregnancy, persistent hydatidform molar pregnancy, choriocarcinoma
