Pregnancy Overview Flashcards
what is a full term pregnancy?
40 weeks of gestation
actually 38 weeks since fertilisation
when does the blastocyst implant into the endometrium?
around day 5-7
which cells help invade into the endometrium?
trophoblast
which hormones increase with pregnancy?
human chorionic gonadotrophin
oestrogen and progesterone
what is the function of hCG?
maintains integrity of corpus luteum (mimics LH) to promote continued progesterone and oestrogen secretion and prevent menstruation
where is hCG produced?
syncytiotrophoblast following implantation of the blastocyst
when do the levels of hCG decline?
once the placenta is established
when is the fetal period?
from 9 weeks to birth
represents rapid growth and physical maturation of organ systems
what is the process of lung maturation?
-are not involved with gas exchange
-filled with fluid
-breathing movements are made which is expulsion of fluid into the amniotic sac via the trachea
where is pulmonary surfactant secreted from?
type II pneumocystis from 24 weeks of gestation
what is the function of pulmonary surfactant?
it facilitates lung expansion at birth and reduces surface tension
what can be administered to stimulate lung maturation for preterm infants?
<34 weeks
glucocorticoids
synthetic surfactant can also be administered after birth
what is the process of renal system maturation?
new nephrons formed until 36 weeks of gestation
-kidneys produce dilute urine but otherwise minimal function (placental fulfils role)
-fetus swallows 7ml- amniotic fluid per hour and produces 300mm/kg of urine per day
-oligohydraminos (too little amniotic fluid) associated with poor renal function
what is the process of digestive tract maturation?
-not fully functional in foetus due to placenta but maturation of enzymes for digestion and absorption occurs
-Crypts and villi develop during weeks 8-24 of gestation then elongate with gestational age
what is meconium?
-greenish mixture of shed interstitial cells, langur mucous and amniotic fluid
-babys first poo
-can get meconium in amniotic fluid due to detail distress - risk of aspiration by the foetus
what is the process of fetal circulation maturation?
-haemopoeisis in the fella liver becomes dominant during the 2nd trimester
-most erythrocytes contain fetal Hb which has greater affinity for oxygen that adult Hb