Physiological Changes in Pregnancy Flashcards
Anterior pituitary produces more? (3)
ACTH
Prolactin
Melanocyte stimulating hormone
High ACTH results in?
Rise in corticosteroid hormones such as cortisol and aldosterone
What conditions tend to get better during pregnancy due to increased ACTH levels?
Autoimmune conditions
What conditions tend to get worse during pregnancy due to increased ACTH levels?
Diabetes
What do the high levels of prolactin do?
Suppress FSH and LH
Increased melanocyte stimulating hormone results in?
Increased pigmentation during pregnancy (e.g. linea nigra, melasma)
What happens to thyroid hormones?
TSH stays normal
but T3 and T4 levels rise
bHCG levels?
Rise, roughly double every 48 hours until week 8-12 then fall gradually
Progesterone levels?
Rise throughout pregnancy, prevent contractions and supress mothers reaction to foetal antigens
Oestrogen levels?
Rise throughout pregnancy
Changes in uterus?
Increases in size
Hypertrophy of myometrium and blood vessels
Changes in cervix?
Cervical ectropion and increased cervical discharge may occur due to increased oestrogen
Changes in vagina?
Hypertrophy of vagina muscles
Increased discharge preparing vagina for delivery but also increases chance of infection
Prior to delivery, what breaks down collagen in the cervix to soften it?
Prostaglandins
Cardiovascular changes?
Increased blood volume
Increased plasma volume
Increased cardiac output
Decreased peripheral vascular resistance
Decreased blood pressure in early and middle term
Varicose veins can occur
Peripheral vasodilation can cause flushing and hot sweats
Respiratory changes?
In later pregnancy:
Tidal volume increases
Respiratory rate increases
Renal changes?
Increased:
- blood flow to kidneys
- GFR (about 50%)
- aldosterone leads to increased salt and water reabsorption
- protein excretion
Uterus and collecting system dilate leading to a physiological hydronephrosis
Haematological and Biochemical changes?
Increased:
- red cell production
- White cell and platelet count
- Clotting factors
- ESR and D-dimer
- ALP levels up to 4x due to placental secretion
Decreased:
- concentration of red cells in increased plasma levels
- albumin
Calcium levels stay the same
Skin changes?
Increased pigmentation
Striae gravidarum
Pruritus (could indicate obstetric cholestasis)
Spider naevi
Palmar erythema
Hair loss postpartum is normal, usually improves within 6 months