Pregnancy and pre-eclampsia Flashcards
What component of the blastocyst is key for the development of the placenta?
Tropohoblast
After the trophoblast implants into the uterine wall, the trophoblast that surrounds the blastocyst differentiates into what two layers. What are these called? Describe them.
Cytotrophoblast - Villous shaped, inner layer of trophoblast, highly proliferative
Syncitiotrophoblast - outer layer, multinucleate, non-dividing
Over the course of pregnancy, the cytotrophoblast layer will repopulate and maintain the syncitiotrophoblast layer.
About 8 days after conception, we get fluid filled spaces known as lacunea, which begin to develop where? What are they precursor to?
- Lacunae
- Intervillous space
Describe what is meant by the intervillous space
Any of the spaces between the placental villi that contain maternal blood
Not long after the lacunae are formed, blood from maternal sprial arteries will enter these lucane. This isn’t deliberate blood flow as such, but obviously there will be blood in those spaces given that it was previously occupied by endometrial tissue before implantation has occured. As such, some blood will leak into these spaces before extravillous trophoblasts are able to migrate and form a plug to stop the blood flow. According to Dr Mcintyre, blood flow continuning would be damaging to the embryo. .
So, our lacunae have been plugged. The next stage involves migration of ?????, resulting in the formation of ????? projections, that extend towards the ?????? plate.
Tertiary villi will form after 3 weeks of gestation, with the villi having an outer layer of ?????, with an inner layer of ????? and vascularised with ???? capillaries. .
So, our lacunae have been plugged. The next stage involves migration of cytotrophoblasts, resulting in the formation of villus projections, that extend towards the basal plate.
Tertiary villi will form after 3 weeks of gestation, with the villi having an outer layer of syncitiotrophoblast, with an inner layer of cytotrophoblast and vascularised with fetal capillaries.
What stuctures are visible on the macroscopic basal plate?
Cotyledons - inside of which yuou would find the villous tree.
Define pregnancy induced hypertension
Onset of hypertension during the second half of pregnancy in the asbsence of proteinuria
Define pre-eclampsia. What is the incidence?
New onset hypertension (systolic>140mmHg, diastolic 90mmHg, that occurs after 20 weeks of gestation, associated with oedema and proteinuria (protein:creatinine ratio >30mg/mmol). - It is important to note that they are many atypical presentations of aclampsia that do not match these criteria especiallly women who have renal disease or are already hypertensive.
6% of UK pregnancies
Eclampsia is the progression of pre-eclampsia. If is associated with the same features as pre-eclampsia, as well as what other clinical features. It occurs in what percentage of pregnancies?
- FIts or convulsions
- Cam cause maternal and/or fetal death
- Occurs in 1-2% of pregnancies
Preterm birth is a baby delivered at <37 weeks after gestation. Extremely preterm is ? weeks, very preterm is ??-?? weeks, moderate to late preterm is ?? to ?? weeks. There are approxmiatelt 60,000 preterm births in UK per year, accounting for 7-8% of pregnancies. 8-10% of preterm births are due to ???? disorders of pregancy, including pre-eclampsia.
Preterm birth is a baby delivered at <37 weeks after gestation. Extremely preterm is ? weeks, very preterm is ??-?? weeks, moderate to late preterm is ?? to ?? weeks. There are approxmiatelt 60,000 preterm births in UK per year, accounting for 7-8% of pregnancies. 8-10% of preterm births are due to ???? disorders of pregancy, including pre-eclampsia.
Fetal growth restriction can be difficult to characterise- sometimes called ???. Define this, and what criteria is used to classify a baby as suffering from fetal growth restriction. What is the incidence?
Fetal growth restriction can be associated with abnormal ublicial artery flow on doppler ultrasound and/oir oligohydramnios(less amniotic fluid than expected for gestational age). Fetal growth restriction can also be associated with pre-eclampsia, or other complications of pregancy.
Failure of the fetus to reach it’s genetitcally predetermiend growth potential.
Results in birthweight in 5th centile of individualised birthweight ratios.
Affects 5-10%
Fetal growth restriction is a major risk factor for ???. Survivors are at an increased risk of ??? and ??? diseases.
- Stillbirth
- Neonatal and adulthood
Many factors thought to contribute to the development of pre-eclampsia. This includes? You cannot cure pre-eclampsia. The only “cure” is pre-term iatorgenic delivery
Genetics
Abnormal placental development
Immune-mediated
Maternal vascular abnormalities
Women with hypertensive disorders of pregnancy are more likely to develop ??? in later life.
Heart disease.
Perinatal = the time before and after birth.
The presentation of pre-eclampsia is varied and different to research, as pre-eclampsia is unqiue to humans, making it diffiuclt to study. Name the more common presentation, allowing with other potential features.
Common (most likely caused by endothelial dysfunction) :
Hypertension
Proteinuria
Oedoma - hands, feet, face
Less common:
- abdominal pain
- headaches
- blurred/flashing vision
- Nausea/vomiting
- Heartburn that doesn’t go away with antacids
- Rapid oedema onset
State risk factors for pre-eclampsia
- First pregnancy/first pregnancy with new partner, first pregnancy in 10 years
- previous history of pre-eclampsia (reccurent risk is about 25%, so still most who have had before won’t have it again)
- genetic history (mother/sister)
- Multiple pregnancies
- Pre-exisiting conditions
- Chronic kidney disease
- Hypertension
- DIabetes mellitus
- Lupus
- Thrombophilia
- Obesity (BMI >30 or possibly 35)
- Increased maternal age (40+)
- IVF also increases risk
- Partners who used condoms,(as opposed to other methods of contraceptives),
