产后生理变化

you know they say that a woman is never the same after she has a baby but your body works pretty hard and it starts working right after the baby is born to get the body back into its pre pregnancy state and it usually takes somewhere along six to eight weeks to occur for most of the organ systems to go back to working the way they did before pregnancy so what happens right after delivery occurs well for some women something like 25 to 50 percent of women so almost half of all women start shivering and these postpartum shivers they usually start within 30 minutes of delivery and they last anywhere from 2 minutes long to being an entire hour long and we're not exactly sure why they occur so we think that it might be related to sudden thermal imbalances from the separation of placenta or maybe it's related to certain medications or anesthesia that's used during the delivery or perhaps even due to bacteria in the blood so we're not exactly sure why they occur but in any case there's no real treatment for them other than to give the woman a warm blanket they tend to resolve on their own so maybe not as clinically significant but it's important to know so that you're not startled when you see them or you experience them for the very first time so starting with the uterus let's talk about what happens after the baby and the placenta are delivered so immediately after delivery the uterus starts to contract so I mean like babies out placenta is out the uterus immediately starts to contract and after a few of those successive contractions the uterine muscles starts to shorten and those contractions also help to constrict the blood vessels that are running through the uterine muscle right and that helps to control any bleeding that might be going on so when you palpate the uterus when you feel for the uterus the uterus should feel more firm and feel more globular than it did in the pregnancy and within about 24 hours after delivery the uro shrinks down so you can feel the fundus which is the of the uterus kind of at the level of the umbilicus so at the level of the belly button and then by one week postpartum the fundus can be felt halfway between the humble Lycus and the pubic symphysis so pretty rapid reduction and then by two weeks you can't feel the fundus anymore and then within six to eight weeks it's returned to its normal size so pretty quick reduction back down to its normal size and the shrinking of the uterus back down to its normal size is affected by a couple of different things so in women who've had multiple babies in the past and in women who in whom the delivery of the baby occurred by c-section rather than by vaginal delivery the uterus tends to be larger right now compare that with breastfeeding breastfeeding tends to cause a quicker reduction in the size of the uterus and a lot of that has to do with a hormone called oxytocin so there's hormone called oxytocin that's released from the brain and the primary function of oxytocin has nothing to do with the uterus the primary function of oxytocin is to contract the ducts of the breast to help release milk but one of the side effects I guess you could say of it is that it also causes the uterus to contract causing it to shrink at a faster rate and that's why women who breastfeed have a quicker shrinking rate essentially of the uterus than women who do not press feed now with regards to what's going on on the inside of the uterus remember that the placenta attaches itself to the decidua basalis the decidua is in where the placenta is attached to the decidua basalis of the uterus right and that decidua basalis that lining of the uterus is left behind after the placenta separates so it's left behind and what it does is it splits up into two different layers though there will be the superficial layer which is shed and the deeper layer which sticks around and it regenerates a new endometrium and when the bloody decision sheds it does so for the first few days following delivery and and and the woman observes that she sees it and it's referred to as lochia rubra lochia rubra meaning red right so it's red lochia and after that the vaginal delivery becomes very watery and that's called lochia that's called lochia serosa and that lochia serosa lasts for about two to three weeks and ultimately that vaginal discharge turns more yellow yellow white color and then it's referred to as lochia alba okay i'll but with alba meaning white okay so you can see that vaginal discharge a significant amount of vaginal discharge lasts for about a month following delivery and it's not just the uterus which contracts to become smaller the cervix and the vagina do the exact same thing so after delivery the cervix which is which is the opening of the uterus through which the baby passes through as you can probably imagine is pretty soft and floppy after delivery the cervix starts to contract and then by one week postpartum you'll see that it's it's somewhere less than one inch dilated and the external a sore the or the external opening of the cervix actually never returns to the shames the same shape that it had before pregnancy so instead of being like this small smooth circular opening it becomes a large sort of horizontal slit after childbirth similarly the vagina is very smooth and dilated after delivery and it's slowly very slowly contracts to shrink down but usually it doesn't reach its pre-pregnancy size and as a swelling reduces the rugae of the vagina come back usually within three weeks or so so the smooth surface is replaced by the typical rotated surface of the vagina and normally it's safe to resume sex about three to four weeks postpartum all right now finally with regards to the return of ovulation and the return of menses that usually occurs within six to eight weeks after delivery in women who don't breastfeed so that's an important distinction in women who do not breastfeed menses and ovulation usually returned within six to eight weeks in women who do breastfeed however ovulation and menses don't return for up to six months during during the time when the woman is breastfeeding and that's because in order to sustain breastfeeding the hypothalamus which is in the brain has to produce a hormone called prolactin right so the hypothalamus produces this hormone called prolactin which is really important for stimulating lactation however prolactin also inhibits like I guess you can say again this is one of the side effects of this hormone prolactin also inhibits sex hormone production which prevents ovulation from occurring in fact in some under developing countries breastfeeding is used as a main method of contraception after delivery after the woman gives birth so those are some of the changes that occur after the baby is delivered