Common pathologies of pregnancy Flashcards
What hormone is first in hormonal cycle?
Estrogen
What happens if progesterone keeps rising in hormone cycle?
Egg fertilised
What does progesterone do to endometrium?
Thickens i/maintains it during second phase of cycle
What does progesterone turn endometrium into?
Decidua
What happens when endometrium turns into decidua?
Increases vascularity
Between glands and vessels the stromal cells enlarge and become procoagulant -> stops bleeding
What develops on the outer edge of the fertilised egg (chorion)?
Trophoblast cells
What hormone does trophoblast cells produce?
Beta-human chorionic gonadotrophin (B-hCG)
What is the target of B-hCG?
Corpus luteum in ovary
What is the function of B-hCG?
Stimulates corpus luteum to produce progestogen, which stops decidua from shedding
What is B-hCG used for clinically?
Basis of pregnancy tests
What do trophoblast cells do apart from produce B-hCG?
Stream off to invades mothers blood vessels and link these vessels up with those of the fetus
What is the forerunner of the placenta?
Chorionic villi covered by trophoblast cells
Case I: woman, 26yrs, missed period, pregnancy test positive, vaginal bleed after 7wks missed period, what is likely happened?
Miscarriage
Case I: woman, 26yrs, missed period, pregnancy test positive, vaginal bleed after 7wks missed period.
US: no fetus present but membranes and decidua lining uterus still there. What had happened?
Miscarriage
What can cause miscarriage?
Chromosomal abnormality
Infection
Maternal issues (ill-health, trauma, hormonal problems)
Case II: women, 32yrs, misses period, 8wks pregnant, small amount of bleeding PV, BhCG raised, US shows thickened lining of endometrial cavity, expanded fallopian tube on 1 side. What is likely diagnosis?
Ectopic pregnancy
Case II: women, 32yrs, misses period, 8wks pregnant, small amount of bleeding PV, BhCG raised, US shows thickened lining of endometrial cavity, expanded fallopian tube on 1 side. Ectopic pregnancy diagnosed. What are options?
Methotrexate
Removal of fallopian tube
Why is methotrexate used for ectopic pregnancy?
Trophoblast cells very sensitive to methotrexate and pregnancy would be expelled
Where is main place for ectopic pregnancy?
Fallopian tube
Case III: woman, 23yrs, sudden severe abdo pain, collapses, pulse fast, BP low, blood given and emergency laparotomy. Several litres of blood in abdomen, blood flowing from fallopian tube area, clamped, removed and sent to pathology. What is likely diagnosis?
Ruptured ectopic pregnancy
Why does low BP result in fast pulse?
Compensatory mechanism: low BP sensed by carotid bodies in neck, which sense partial pressure of O2 and tells heart to work harder
What is an ectopic pregnancy?
Pregnancy in wrong anatomical site
Why can ectopic pregnancy rupture?
Lack of proper decidual layer and small size of tube predispose to haemorrhage and rupture
Case IV: woman, 32yrs, +be pregnancy test, 7 weeks pregnant, minor bleed, US of uterine cavity shows some placental tissue but no fetus. Fallopian tubes normal. B-hCG raised. What is likely diagnosis?
Miscarriage
Case IV: woman, 32yrs, +be pregnancy test, 7 weeks pregnant, minor bleed, US of uterine cavity shows some placental tissue but no fetus. Fallopian tubes normal. B-hCG raised. On microscopy, enlarged chorionic villi with abundant trophoblasts. What is likely diagnosis?
Molar pregnancy
What happens when parents methylate the genes in their ova/sperm?
Switches off different genes
What is the result of the parents methylating different genes in their ova/sperm?
Mother: promotes early baby growth
Father: promotes early placenta growth via trophoblast proliferation
What is the overall effect of methylation of genes in normal fertilisation?
Balanced growth of baby and placenta
What causes a molar pregnancy?
Usually caused by 2 sperm fertilising 1 egg with NO chromosomes
Result is imbalance in methylated (switched off) genes
What happens as a result of a molar pregnancy?
Trophoblast cells proliferate because they have too many of dad’s methylated genes
= overgrowth of placenta
= no or all but non-existent fetal growth
If molar pregnancy persists what can it cause?
Malignant tumour called choriocarcinoma
What is the treatment for a molar pregnancy?
If B-hCG returns to normal = no treatment
If B-hCG stays high = methotrexate
What is nuchal thickening a sign of?
Trisomy 21 (Down syndrome)
What does TOPFA stand for?
Termination of pregnancy for abnormality
When there is no fetal heart movement what is this called?
Intrauterine death (IUD)
How much does a normal baby at term weigh?
3.3kg
What is likely if mother has poorly controlled diabetes and there is an IUD/stillbirth due to baby being too big?
Diabetic cherub
Why does baby get so big in diabetic mother?
Glucose crosses placenta and baby cannot reduce glucose, insulin increases too, so baby has hyperinsulinemia and hyperglycaemia = massive growth of muscle/fat
What are babies with long-term hyperinsulinemia and hyperglycaemia susceptible to?
Intrauterine death
What are the problems of diabetes in pregnancy?
Malformations
Huge babies that obstruct labour
Intrauterine death
Neonatal hypoglycemia
What is a fresh stillbirth?
Stillbirth in labour
What is acute chorioamnionitis?
Acute inflammation from ascending infection from vagina and get into amniotic sac
What is the presentation of ascending infection?
Mother ill: fever and raised neutrophils
Or mother well
What is the presentation in baby if ascending infection?
IUD
Ill first days of life
Cerebral palsy later in life - hypoxia of labour
Do opiates cross the placenta?
Yes
Why would a IV heroin addict have her baby pre-booked in neonatal unit?
Baby can be treated for heroin withdrawal for first 5 days of life
What is a common cause of IUD and neonatal illness?
Overtwisted cord
What is the APGAR score?
Score to quickly summarize health of newborn baby against infant mortality: A: appearance P: pulse G: grimace - response to stimulation A: activity - muscle tone R: respiration
What is placental abruption?
Separation of placenta from uterine wall
What does placental abruption result in?
Hypoxia in baby
Sometimes antepartum haemorrhage in mother
What is bleeding into the area where the placenta has come away from the uterine wall called?
Haematoma
What are causes of placental abruption?
Hypertension
Trauma
Other: cocaine
