Pregnancy/Labour Flashcards
How can human pregnancy be divided into?
3 Trimesters - defined by experience
1st trimester: 0-13 weeks - If the pregnancy gets to the end of the 1st trimester it is very likely to continue successfully.
2nd trimester: 14-26 weeks - Without a neonatal intensive care they are highly unlikely to survive.
3rd trimester: 27-40 weeks
There are maternal changes throughout the 3 trimesters - 1st trimester difficult to see they’re pregnant. 2nd and 3rd you can see they are pregnant. The placental changes are complex
Describe the maternal changes seen from the first trimester onwards?
Altered brain function [1st & later]
Altered hormones [1st & later]
Altered appetite (quantity and quality) [1st & later] – GI imbalance, Hyperemesis gravidarum (morning sickness)
Altered emotional state [1st & later] - postnatal depression
Altered immune system [1st & later] - Factors suppress mother’s immune system so foetus and placenta aren’t rejected as foreign bodies
Describe the maternal changes seen from the second trimester onwards?
Increased blood volume [2nd & later]
Increased blood clotting tendency [2nd & later]
Decreased blood pressure [2nd] - Postural hypotension, fainting
Altered fluid balance [2nd & later]
Describe the maternal changes seen from the third trimester onwards?
Increased weight [3rd]
Altered joints [3rd] - joints become more flexible
Describe maternal changes in the endocrine system
HCG - reaches the peak around 8 weeks during gestation in the 1st trimester. Correlated to morning sickness. Falls of after first trimester as placenta is then fully developed and can take over hormone function from the corpus luteum.
Progesterone, oestrogen, and placental lactogen all increase gradually. This increase is due to the gradually increase in the size of the placenta. Progesterone>Oestrogens>Placental lactogen
These hormones fall when the placenta is delivered. Progesterone and oestrogen is required to maintain pregnancy - this is important.
All of these hormones are produced in the placenta
Summarise the risks pregnancy has on the mother?
Relatively little risk in the early parts of pregnancy, the main risk to maternal health (or life) linked to delivery
Define conceptus
everything resulting from the fertilised egg (baby, placenta, fetal membranes, umbilical cord)