Pregnancy Flashcards
How long is the typical menstrual cycle?
28 days
What is the first phase of the menstrual cycle?
follicular phase
when does the LH surge occur?
around day 14 (ovulation)
What is the second phase of the menstrual cycle?
Luteal phase
What hormone does the follicle produce?
Oestradiol - type of oestrogen
What does the ovulating follicle ( corpus luteum) produce?
progesterone
If implantation occurs what does the implanting embryo produce?
ii. what can this be used for?
hCG
ii. pregnancy tests
What hormones does the placenta produce?
hPL - human placental lactogen - hCG levels decrease
Placental progesterone
Placental oestrogens
During pregnancy what hormone does the anterior pituitary gland release?
Prolactin (lactogen) - required for milk production
what does placental progesterones and hPL do to the mother?
ii. what condition can this lead to?
makes them insulin resistant - sugar isn’t taking up by the mother but rather given to the foetus
ii. if mother is already insulin resistant it can led to gestational diabetes
When does foetal organogensis?
around 5 weeks
what are the complications of diabetes?
Foetal complications
Congenital Malformation
Prematurity
Intra-uterine growth retardation (IUGR)- poor growth of a foetus
Gestational diabetes only:
Macrosomia - a newborn who’s much larger than average. They are usually over 90% centile for size. Problem in delivery
Polyhydramnios - excess of amniotic fluid in the amniotic sac
intrauterine death
Neonate complications
Respiratory distress
Hypoglycaemia
Hypocalcaemia
caudal regression syndrome
Genital & GI abnormalities
What is the pathophysiology of Macrosomia?
- Mothers Hyperglycaemia is passed to foetal hyperglycaemia via placenta
- Foetus’s pancreas needs to create more insulin - hyperinsulinemia
- High insulin leads to growth in size
- As soon as Baby is delivered it is cut off from the mothers high sugar supply. The baby is quiet slow at removing the high level of insulin so neonatal hypoglycaemia occurs.
How do you manage Diabetes in pregnancy?
A. Controlling diabetes: T1 and T2
- Pre-pregnancy counseling:
Good sugar control pre conception - limits risk of congenital malformation
- Folic acid - given for at least 3 months before pregnancy. give 5mg
- Retinopathy eye checks - every 10 weeks in pregnancy
- Blood pressure:
Labetalol (most common)
Nifedipine
methyldopa
- High risk pregnancy:
Aspirin 150mg at 12 weeks - reduces risk of pregnancy induced hypertension
Type 2 specific:
change from tablets to insulin.
Avoid:
ACE inhibitors - increase risk of teratogenic development
Statin - also increase risk of teratogenic development
B. Controlling Diabetes: for T1,T2 and gestational
- Diabetic diet
- Blood sugar control:
pre-meal <4 - 5.5 mmol/L
2h post meal <6-6.5 mmol/L
- Monitor HbA1c
- Monitor BP
- Maintain good blood glucose during labour:
if the patient is on insulin switch to IV insulin and IV dextrose
Pharmacological: Treating diabetes
T1 - Insulin
T2 - metformin. will probs need insulin later
GDM - can be Lifestyle changes only. However if not use Metformin and may need insulin later.
How should you check that gestational diabetes has gone?
6 week post natal fasting glucose or GTT
if the diabetes has persists after 6 weeks then it is undiagnosed T2DM
What are the implications of Gestational diabetes?
50% of patients will go on to form T2DM
5% will go on to form T1DM
How do you prevent patient from getting diabetes after GDM?
Mainly lifestyle management
- Low weight
- Health diet:
Low refined sugar
Predominant starch
Low saturated fat
Low energy food
- Aerobic exercise
Patients should be encouraged for annual fasting glucose so they can catch their diabetes early
When does gestational diabetes usually present?
third trimester
what effect does Hypo/Hyperthyroidism on pregnancy?
reduces fertility
causes anovulatory cycles - menstrual cycle with no ovulation
what physiological changes occur to the thyroid during pregnancy?
it thickens - mother needs to make more thyroxine as this is important for neonatal development.
Also needs to make more to maintain normal concentration
How do you manage hypothyroidism in pregnancy?
- Pre-existing hypothyroidism:
Want to control it pre pregnancy
When pregnant:
increase thyroxine dose by 25mcg ASAP once pregnancy is suspected
Check TFTs monthly for first 20 weeks then 2 monthly until term
increase thyroxine if TSH is rising. Aim for TSH <3mU/l
What are the risks of untreated hypothyroidism?
Increased abortions
Preeclampsia
abruption
postpartum haemorrhage
preterm Labour
Foetal neuropsychological development:
average child will have 7 IQ points less if their mother has hypothyroidism
What effects does high hCG have on TSH?
suppresses it as it increases T4
What does High hCG cause?
Hyperemesis - vomiting in pregnancy
How do you distinguish between Hyperemesis and hyperthyroidism?
Gestational hCG associated thyroxicosis:
Hyperemesis gravidarum - hCG increase - causes decreases TSH
Not TRab antibody positive
improves after 20 weeks. If not then it is hyperthyroidism (graves disease)
What are the risks of Hyperthyroidism in pregnancy?
infertility
Spontaneous miscarriage
stillbirth
Thyroid crisis in labour
transient neonatal thyrotoxicosis
what is the most common cause of hyperthyroidism in pregnant women?
Graves disease
other causes:
TMNG
toxic adenoma
Thyroiditis
How do you manage Hyperthyroidism in pregnancy?
Wait and see:
Hyperemesis will settle
Graves may settle as pregnancy suppresses autoimmunity
Check TRAB antibodies
Beta blockers can be helpful
Low dose anti-thyroid drugs: delay as long as possible and start at lowest dose possible.
Propylthiouracil - 1st trimester - thought to have less effects on embryogenesis. Can be toxic to the mother so only use in 1st trimester
Carbimazole 2/3rd trimester
side effects:
Carbimazole:
embryopathy in 1st trimester
Scalp abnormalities
GI abnormalities
Choanal & oesophageal atresia
Propylthiouracil:
Risk of liver toxicity in mother
Antibodies:
check TRAb antibodies during pregnancy - ideally third trimester.
TRAb antibodies cause neonatal transient hyperthyroidism
What is postpartum thyroiditis?
occurs when patient with diabetes after delivery
Mother develops transient over active thyroid (around 6 weeks) and then under active thyroid. Can persist up to a year
Forms a small, diffuse non tender goitre
Hypothyroid phase is associated with post natal depression
Only treat Hypothyroidism - give thyroxine if symptomatic
