Peak of prostaglandins occurs in what stage:
Ans. (c) 3rd stage of LaborRef High risk pregnancy 4th ed. by James et.al, ch 75- Normal third stage of LaborThere are four stages of labor* The first stage is from the onset of true labor to complete dilation of the cervix.* The second stage is from complete dilation of the cervix to the birth of the baby.* The third stage is from the birth of the baby to delivery of the placenta.* The fourth stage is from delivery of the placenta to stabilization of the patients condition, usually at about 6 hours postpartum.PROSTAGLANDINS* Prostaglandin F (PGF), PGF2a, and oxytocin are the biochemical agents primarily involved in the third stage of labor.* During the first and second stages of labor, only PGF2a and oxytocin are significantly raised in maternal plasma compared with pre-labor concentrations.* At 5 minutes after birth, maternal PGF and PGF2a concentrations peak at about twice the levels found at the commencement of the second stage. A rapid increase in prostaglandin concentrations is also found in umbilical cord venous blood, suggesting that this postpartum prostaglandin surge originates in the placenta.* After placental separation, the concentrations decrease but at rates slower than the metabolic clearance of prostaglandin, indicating that its production continues in the decidua and myometrium.* Plasma oxytocin also drops to prelabor levels within 30 minutes of delivery, unless sustained by exogenous infusion.Also KnowHormonesPeak level at:OxytocinAt birthProlactinLevels decrease during labor but then rise steeply at the end of labor and peak with birth.
1st stage of Labor
2nd stage of Labor
3rd stage of Labor
Before 1st stage of labor
Characteristics of Normal Labor