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you know when most of us think of pregnancy we focus down here at what's going on at the level of the uterus but a healthy pregnancy has a lot to do with a properly functioning pituitary gland up here in the brain the pituitary gland makes the hormones that are essential for life and in pregnancy it grows and not just by a little but by close to 150 percent and that a lot of that growth is due to cells called lactose so these cells in the in the pituitary gland called lacto troves increasing in number electret rows are these cells that make a hormone called prolactin so they make this hormone called prolactin and prolactin stimulates breast growth and milk production so as you can imagine it's really important during pregnancy so that's all good but the problem is that while the pituitary gland grows substantially during pregnancy the blood supply to the pituitary doesn't increase by as much so that kind of looks like this where if if this is a normal pituitary gland right that's what a normal pituitary gland looks like and this is its blood supply in pregnancy this gland is way bigger is way bigger but its blood supply isn't that much greater so throughout the pregnancy I guess you can say that the pituitary gland is in a really fragile state where it's only receiving as much blood as it needs no more than that and it's really it's really pretty susceptible to being in a situation where its blood supply doesn't meet its requirements which can lead to ischemia or a lack of oxygen supply and eventually it can lead to death of the cells of the pituitary gland and that death of the cells in the in the pituitary gland is referred to as Shi hand syndrome right so the topic of this video so when do we have to worry about all of that well we have to worry about it in any case of excessive blood loss so any sort of trauma resulting blood loss or in the case of postpartum hemorrhage right which refers to when you have an excessive blood loss during delivery and in those cases the pituitary gland isn't able to withstand that and blood supply and in addition to that remember that whenever you have a loss of blood volume whenever you have a loss of blood volume the blood pressure in the body drops and the body responds to that dip in blood pressure by clamping down on all of the blood vessels right which is referred to as vasoconstriction right so the body responds to the dip in blood pressure by vaso constricting to increase the blood pressure and that clamping down on the blood vessels of the pituitary further reduces the amount of blood that's going in to the pituitary gland and so in situations of acute blood loss again such as in trauma or postpartum hemorrhage you can have death of the pituitary cells all right so what does that mean why is that significant if you have death of the pituitary cells well firstly keep in mind that this isn't an all-or-none type of picture we could have death of a few many or all of the cells usually it's just the lacto troughs that die in which case you end up with a prolactin deficiency and because of that if you have a prolactin deficiency the breasts will reduce in size and the mom isn't able to breastfeed after delivery and usually this is actually how this syndrome is discovered the mom isn't able to breastfeed after delivery and that warrant sort of an investigation into the cause of why that's happening now so you can have the death of the lactose you can also have death of the cells that make hormones involved in the reproductive axis and that could lead to a lack of menstruation or an inability to regrow shaved pubic hair or axillary or underarm hair right or or less commonly but still possible you can have loss of all of the cells of the pituitary gland and that could lead to symptoms of low thyroid hormone such as weight gain cold intolerance and you can also have symptoms of cortisol deficiency which could lead to fatigue or feeling tired or even life-threatening low blood pressure and the main treatment for Sheahan syndrome is replacing these hormones that you've lost at the levels that the body would normally make them and we're getting better and better at preventing this disease from occurring altogether because now nowadays we take simple measures to make sure that if the mom suffers any form of acute blood loss we replace that blood volume as quickly as we can all right so that's a little bit of information on Chi Hanson