Common Pathologies of Pregnancy 1, 2 & 3 Flashcards
What are the common symptoms of miscarriage?
- Bleeding
- Abdominal pain
- Cramping
- Tissue passing from the vagina
What are the common causes of miscarriage?
- Unknown cause very common
Other causes include:
- Chromosomal abnormality
- Infection
- Maternal health issues (ill-health, trauma, hormonal problems)
What are the pathological processes involved in miscarriage?
1 - Fetus is ejected from the uterus
2 - Membranes and decidua lining uterus are left behind in the uterus
How is miscarriage defined?
Miscarriage is also known as the spontaneous abortion or death of the embryo or fetus before 20 weeks or before the fetus is able to support itself independently
What is the definition of an ectopic pregnancy?
When the embryo develops outside the uterus, in the wrong anatomical site (most commonly in fallopian tube)
What are the common symptoms of an ectopic pregnancy?
- Vaginal bleeding
- Sudden lower abdo pain
- Raised hCG
What are the pathological processes involved in ectopic pregnancies?
1) Cilia of fallopian tubes become damaged
2) Embryo fails to travel along the tubes into the uterus
3) Embryo implants into fallopian tube
What are the medical signs that can indicate an ectopic pregnancy?
- BhCG raised
- USS will show thickened lining of endometrial cavity and expansion of a fallopian tube
How are ectopic pregnancies treated?
Medical - Methotrexate will terminate the growth of the fetus if delivered early enough, resulting in an abortion
Surgical:
- Salpingostomy = removal of the pregnancy from the tube
- Salpingectomy - removal of the entire fallopian tube
What is a molar pregnancy?
An abnormal type of pregnancy that occurs when a non-viable fertilized egg implants in the uterus but fails to go to term.
The non-viable fertilized egg often does not contain original maternal nucleus
What are the symptoms of a molar pregnancy?
- Painless vaginal bleeding usually occuring during 4th or 5th months of pregnancy
- Enlarged ovaries or uterus
Under the microscope, how would a molar pregnancy appear?
- Enlarged abnormal chorionic villi with abundant trophoblasts
What are the pathological processes that occur in molar pregnancies?
1) 2 sperm fertilise one egg with no chromosomes
2) This results in an embryo with 2 lots of dad’s methylated genes
3) Due to the methylation of dad’s genes (adding methyl to stretches of DNA), there is massive overgrowth of trophoblast cells and therefore overgrowth of placenta
4) The over methylated embryo means that there will be none or very little fetal growth
What are the complications of molar pregnancies if left untreated?
- Choriocarcinoma (malignant)
How are molar pregnancies treated?
1) If BhCG returns to normal - no further treatment required
2) If BhCG stays high - cure by methotrexate
What are the medical signs and symptoms of Down syndrome (Trisomy 21) during pregnancy?
1) USS showing nuchal thickening
2) Cardiac abnormalities (enlarged ventricles)
Following detection of Down Syndrome signs on USS screening, how is the diagnosis of Down Syndrome confirmed?
Amniocentesis - a small amount of amniotic fluid is collected and tested for DNA abnormalities (Trisomy 21)
What are the common issues encountered during pregnancy when a mother has poorly controlled diabetes?
Macrosomia - abnormally large baby
Why does poorly controlled blood glucose levels in the mother result in an abnormally large baby?
- Glucose in the mothers blood stream freely crosses the placenta
- The baby does not have the ability to reduce or control the amount of glucose it is receiving
- The excess delivery of glucose across the placenta drives up the babies insulin levels
- The combination of longterm high insulin and high glucose results in massive growth of the unborn baby
What are some of the complications of poorly controlled diabetes during pregnancy?
1) Malformations
2) Huge babies that obstruct labour
3) Intrauterine death
4) Neonatal hypoglycaemia
What are the risks to the unborn baby if the mother suffers with a fever/infection during pregnancy?
Acute chorioamnionitis = Ascending infection which spreads upwards from the vagina into the amniotic sac
What is the pathophysiological presentation of acute chorioamnionitis?
1) Acute inflammation of the placenta with neutrophils present in fetal membranes, placental cord and fetal plate of placenta.
What is the most common organisms responsible for acute chorioamnionitis and from where do these organisms typically originate?
E.coli
- From perineal or perianal areas
How does acute chorioamnionitis (ascending infection) present in the mother and baby?
Mother:
Fever and raised neutrophils
Baby:
Ill during the 1st days of life which are spent in the neonatal unit
The baby often suffers with cerebral palsy later in life
What is the process by which ascending infection can affect the baby’s brain?
- Increased volume of neutrophils produces a cytokine ‘storm’
- This cytokine ‘storm’ activates some brain cells which then get damaged by the normal hypoxia of labour
What issues will a newborn baby face when born from a mother who is a heroin addict?
1) Heroin withdrawal
What is abruption and what are its associated complications?
Abruption = separation of placenta from uterine wall
- Hypoxia in baby
- Antepartum haemorrhage in mother
- Haematoma on the uterine wall
What are the causes of abruption?
1) Hypertension
2) Trauma
3) Cocaine
Why would progesterone levels keep rising at the end of a monthly menstrual cycle?
Egg has become fertilised
What does progesterone do to the endometrium?
Thickens it
What changes happen to the endometrium in the early stages of pregancy?
Vascularity increases
What cells are found on the outside of a fertilised egg?
Trophoblast cells
Which hormone is produced by trophoblast cells?
Beta-human Chorionic Gonadtrophin (B-hCG)
What is the target of B-hCG?
Corpus luteum in ovary
What is the purpose of B-hCG acting on the corpus luteum?
It stimulates the corpus luteum to produce progestogen
Progestogen stops the thickened layer of endometrium (decidua) from shedding
Which hormone is detected in pregnancy tests?
B-hCG
Apart from producing the B-hCG hormone, what is the other function of trophoblast cells?
They produce placental cells
When the trophoblast cells invade mothers blood vessels (to form the placenta) which cells stop bleeding?
Decidual cells
What is methotrexate used for in pregnancies?
To terminate an ectopic pregnancy
Apart from using medication, what other treatment options are there for ectopic pregnancies?
Surgery - removal of fallopian tube
What is a common cause of intrauterine death?
Overtwisted cord
