hello everyone in this lecture we will cover the female reproductive system and these are our learning objectives here we have a midsagittal view of a female pelvic area we can see the main organs of the female reproductive system which includes the ovary the uterine tube which used to be called fallopian tube the uterus and the vagina and here it is being pointed specifically to the vaginal canal the female external genitalia includes the clitoris the label majors and the label - keep in mind that here we are looking at half of the pelvic area so in reality there are two ovaries show uterine tubes and also two labia minora into labia majora so labia majora and labia minora is the plural of labium ages and labia - that we are seeing here we thing labia majora we find adipose tissue and on the surface of the labia majora we see hair and the labia majora is homologous it is equivalent to the scrotum in males media - labia majora we find labia minora in the labia minora kind of extent and in circles the clitoris forming the previews of the clitoris now the clitoris that we see here is the female or a dietitian and it's homologous it is equivalent to the corpus cavernosum in males we can see here the female accessory glands which are called urethral glands and the greater vestibular gland the greater vestibular glands are the female version of the Mayo boo boo retro glands and we will learn that like the Mayo boo boo retro glands during sexual arousal the greater vestibular glands secrete mucus very near to the vaginal entrance also in this diagram we see the pubic symphysis and anterior to the pubic symphysis we see the Mons pubis which is this fairy pet the as of this is just for cushioning it provides some extra cushion between skin and pubic bones that are right under it then posterior to the pubic symphysis we find the pelvic cavity and within the pelvic cavity we find the pelvic organs that we are seeing here as you can see right posterior to the pubic symphysis we find a urinary bladder in leaving the urinary bladder we see the urethra which extends down towards the external urethral orifice here in the back we find the rectum which leads to the anus and the rectum basically runs parallel to the vaginal canal such that the posterior aspect of the vaginal canal is in very close proximity to the rectum now the female primary sex organs are the ovaries and inside the ovaries is where we find the old signs that water read inside the female at the time she was born when we talked about males reproductive system we saw a system of ducts associated with the testes then Mayo garnets now in the females we will also find a system of dots associated with the ovaries the female garnets so the system of dots that are used to transport the female sex cell the female gamete includes the uterine tubes which actually transports the egg that gets expelled out of the ovary towards the uterus and then the uterus is associated with the vagina now the uterus is almost entirely muscle so it is just a big thick muscle in this part of the uterus that's associated with the vagina is called the cervix and in the cervix we find the cervical opening in the cervical opening which is very tiny is what gets to be around 10 centimeters open during labor so for childbirth to happen the cervical opening gets extremely wide in comparison to the size it normal is here we have a stated view of the uterus it's like we are looking at the back of a woman we see the uterus and on each side of the uterus we find the uterine tubes and the ovaries we have several ligaments holding the uterus the uterine tubes and the ovaries in place in this thing that looks like wings is what we call broad ligament the broad ligament as the name implies is very broad and it encloses the ovaries the uterine tubes and the uterus the broad ligament attached to the sides and four of the pelvic cavity and with that it limits the side-to-side movement of the uterus also because of its orientation the broad ligament kind of divides the pelvic cavity into tube the interior and the posterior surface here on the superior border of the broad ligament we see the uterine tube which is also called fallopian tube now the ovaries are stabilized by three structures the ovarian ligament the misc ovarian and the suspensory ligaments the male's ovarian is basically a thick fold of broad ligament the ovarian ligament is what holds the ovary to the uterus and the suspensory ligament of the ovary is what holds the ovary to the pelvic wall now very importantly passing through the suspensory ligament we find the ovary major blood vessels in there over imageable vessels include the ovarian artery and ovarian vein in these blood vessels enter the ovary at a place called ovarium hilum and we have used the word helium before for lungs and kidneys and helium is the place where blood vessels and nerves get in and out of an organ so here in the ovary the ovarian helium used to where blood vessels and nerves get in and out of the ovaries and ovarian helium is found at the place where the ovary attached to the men's ovarian now the ovaries are kind of suspended in the of a cavity right and here associated with the ovaries we find the uterine tube and at the end of the uterine tube we'd find a thin brie and the fimbriae is these finger-like projections that are associated with the ovaries and the function of this fing brain is to pick up the egg that's released by the ovary into the pelvic cavity and move the ovulated egg into the uterine tube so basically the uterine tube has the same function as the Mayo ductus deferens right and in fact the uterine tube is homologous to the ductus deferens when we talked about males we said that anna sterilization procedure is vasectomy and in fact to me the vas deferens or ductus deferens get cut now in the case of females we have the two ball addition so tubal ligation is basically the counterpart of vasectomy in tobo Legation the uterine tubes get cut they are tied off and that prevents the egg from moving towards the uterus and consequently prevents sperm cells from encountering the egg in other words it prevents the sperm from uniting with the egg and with that two bola Gatien prevents pregnancy here we have a superior view of the female pelvic cavity we see the ovarian ligament that anchors the ovary to the uterus we see the suspensory ligament of the ovary that anchors the ovary to the pelvic wall we can see the uterus sacral ligament which as the name suggests extends from the uterus to the sacral region and we see the round ligament which extends anteriorly and this is the ligament that passes through the inguinal canal now based on their position we can guess what the uterus sacral and the round ligaments do right so since the uterus sacral basically attached the uterus posteriorly the uterus sacral ligament prevents the neuters from moving anteriorly so it prevents the interior movement of the uterus because it will hold it back in the round ligament that extends anteriorly prevents the posterior movement of the uterus now the Cardinal ligaments that we are seeing here they run transversely so they are under the broad ligament and since they run transversely they go from the base of the uterus to the walls of the pelvis and they create a little floor for the uterus and they prevent the uterus from moving inferiorly you need to keep in mind that the uterus is literally suspended in the pelvic cavity and in order to keep it in place it's necessary to have several ligaments ligaments in different directions to hold it in place because remember the uterus does a lot of moving around like during the menstrual cycle the uterus is going to contract to help to eliminate the blood that's not necessary since pregnancy did not happen and if fertilization of an egg happens and the embryo is implanted the uterus has to grow many times its size and it needs to have enough anchoring points to handle a baby doing gymnastics within it so we have all these ligaments to hold the uterus in place to give the uterus they encourage necessary for the uterus to undergo all these major changes now here on the right we see a superior view from a cadaver we see the uterus and on tiller to the uterus we would find the urinary bladder like it is being shown here in the diagram on the left on each side of the uterus we see the uterine tubes they infundibulum the ampulla and the Isthmus and we see the ovary and ovarian ligament now the infundibulum the ampulla in the Isthmus together with the fin brie which are these finger-like projections that we can see here in the gram on the left there are all different regions of the uterine tube when ov elation occurs the egg is released from the ovary the egg actually gets expelled out into this cavity and what's amazing is that the Fein brain actually manages to pick up the egg from basically the pelvic cavity and transport the egg toward the infundibulum of the uterine tube and then the egg moves towards the uterus now if the fimbria fails to pick up the ovulated egg the egg can actually enter the pelvic area and it gets digested and reabsorbed by immune cells now if by any chance the fertilized egg gets implanted in the pelvic cavity or implanted in any other place that's not within the uterus so in the fallopian tubes the ovary cervix any other place that's not the uterus we have what's called a topic pregnancy an ectopic pregnancy is a serious condition that can be life-threatening for the mother if it is left untreated there is no possible way to save an ectopic pregnancy all week topic pregnancies need to be terminated if you look at this section of the ovary we see that the ovary is surrounded by the germinal epithelium and the German epithelium is basically a layer of simple cuboidal cells the named germ now epithelium is very misleading because this is just a regular epithelium that covers the surface of the ovaries the germ no epithelium does not give rise to any other sites deep to the German epithelium we see the tunica albuginea in the tunica albuginea like in males it is a membrane that covers the garnet so the tunica albuginea in the females is a membrane that covers the ovary deep to the tunica albuginea we see the ovary cortex and deep too that the ovary medulla so the ovary medulla this middle part and it is the place where we find blood vessels and the blood vessels get into the ovary through they ovarian hilum associated with the cortex of the ovary we find the primordial follicles and within the primordial follicles we find the primary oocytes the primary oocytes is what developed during the female fetal development the primordial follicles with the other sites within it mature into larger and larger follicles and eventually the follicle fuses with the outer layer of the ovary and then the outside that was inside the follicle gets ejected out of the ovary into the pelvic cavity and then it is picked up by the femme Brahe and moves into the uterine tube the process of producing eggs is called all Genesis and all banya is the female reproductive stem cell that during fetal development gave rise to the primary oocytes so the primary oocyte developed as the female fetus was developing and this primary oocytes are dormant until the female reached puberty and once the female reached puberty primary oocytes start to develop into secondary oocytes and the secondary or cyant is what is actually released every month and the release of the secondary oocyte the release of the mature egg is what is called ovulation so as I mentioned before the ovary has two parts the outside perimeter is the cortex and the inside the middle is the medulla if we look at the cortex of the ovary we find the immature eggs which are called primary oocytes now the primary oocytes are found within primordial follicles so each or site is surrounded by a follicle and the follicle is kind of a little cushioning pillow that surrounds protect and nourish the egg so each one of this primary or site has a follicle around it and they are called primordial follicles because primordial means that he has been there since the beginning so since the day the baby girl is born she has the primary oocytes so she has the immature eggs we think the primordial follicles now what happens is that when females reach puberty the primordial follicles start to develop and primordial follicles develop your response to hormones and as they develop they become larger until they reach a mature stage in the old site inside the mature follicle is what gets ovulating so once the mature follicle fuses with the outer layer of the ovary the old site is released out into the pelvic cavity in this cells that made the follicle which are called follicular cells is staying in the ovary in these follicular cells that stay behind in the ovary they develop into what is called corpus luteum and corpus luteum literally means yellow body so corpus luteum comes from the follicular cells after they mature all site was ovulated now the corpus luteum cells secrete an immense amount of progesterone in this massive amount of progesterone produced by the corpus luteum supports the growth of the endometrium which lines the inside of the uterus and this makes sense because if the released egg becomes fertilized the growing endometrium is ready to support the fertilized egg now if fertilization does not occur the corpus luteum degrades into corpus albicans which literally means white body and this is basically corpus luteum dead cells it's like a scar tissue that used to be the corpus luteum on average this all happens in 28 days but it could take from 21 to 35 days depending on the woman and after it finishes it starts again so it is a cycle and since it happens in the ovary this is called ovarian cycle we divide the over sico in two phases the follicular phase which is free ovulation and the luteal phase which is post of elation so thinking about the average female that has a psycho of 28 days the follicular phase which is the pre ovulation phase that the period at which the follicle is growing hence the name follicular phase it would take the first 14 days of the 28-day cycle and after day 14 then we have the beginning of the post ovulation and that is the luteal phase and that goes until day 28 so the luteal phase is called luteal phase because in that phase we have the presence of the corpus luteum right so really around the 14 is when we expect the ovulation to happen so we expect the release of an egg to happen around day 14 mid ovarian cycle the ovarian cycle starts with the growth of primordial follicles and this growth is stimulated by a hormone called follicular stimulating hormone FSH as the name suggests the follicular stimulating hormone stimulates the follicle to grow as you can see as the ovarian follicle matures it accumulates lots of fluid within it in this actually creates a bulge on the surface of the ovary in this bulge on the surface of the ovary can sometimes cause what we call ovulation pain because the swollen bulge can actually push nerves in the pelvic region and that can cause the female to feel pain now the follicle grows for about 14 days and at day 14 so middle Varian cycle the egg is ready to be released so what happens is that the mature follicle fuses with the outer layer of the ovary and then they mature aside to be ejected out of the ovary but this fusion of the mature follicle with the outer layer of the ovary happens under the stimulation of another hormone called luteinizing hormone LH so a spike in the concentration of the lutheran izing hormone in the blood string leads to the fusion of the mature follicle with the outer layer of the ovary and then ovulation happens now LH luteinizing hormone as the name suggests it is the hormone that leads to the follicle cells that were left behind to turn into the corpus luteum that we see here and the corpus luteum under a simulation of the luteinizing hormone secretes lots of progesterone and this progesterone causes the endometrium of the uterus to grow and get ready for a possible fertilized egg to be implanted now if fertilization doesn't happen if there is no way in view to be implanted the corpus luteum turns into corpus albicans and then corpse alba cams is basically scar tissue it doesn't produce any hormones and the entire cycle repeats again so the cycle starts with a spike of the follicular stimulating hormone FSH which stimulates the growth of the primordial follicles and it ends with the formation of the corpus albicans now after ovulation happens the egg is picked up by the thin brie which is one of the regions of the uterine tube so the uterine tube is binding to regions we have the same brain the infundibulum the ampulla dismiss and the isthmus is what actually attached to the uterus and histologically uterine tubes have three layers the inner lining of the uterine tube consists of a new cosa it has ciliated in no ciliated columnar cells and you can see them here we have sales with cilia and cells without cilia and the cilia actually helps to transport so two ways they released egg towards the users now deep to the cilia didn't know ciliated columnar epithelium we find layers of smooth muscle in this layer of his move muscle create peristaltic waves of contraction that help to move the egg towards the uterus as well in covering the outside of the uterine tubes we find a protective serous membrane that helps to prevent friction damage so the mature oocyte is released by the ovary into the pelvic cavity and then it gets picked up by the fin brie which are these finger-like projections that cover the surface of the ovary then the egg moves toward the infundibulum then the ampulla and then the Isthmus and it usually takes around three days for the egg to travel the length of the uterine tube before the egg reaches the lumen of the uterus the egg is transported toward the uterus due to a combination of peristaltic movements of the smooth muscle layer and the ciliary action of the epithelium that lines the inside of the uterine tube and during this transportation from the infundibulum to the uterus is when usually the egg gets fertilized so fertilization happens usually 12 to 24 hours after ovulation and it is most likely happening at the ampulla region which is the longest region of the uterine tube now the uterus is this pear-shaped thick walled muscular organ we think the pelvic cavity and as I mentioned at the beginning the uterus is suspended by several ligaments within the female pelvic cavity the uterus is used for nothing other than the development of an embryo and since the uterus is a very muscular organ it mechanically protects the developing embryo and fetus and besides that they uterus nutritionally supports the developing embryo and provides the means to remove waste produced by the developing embryo as well now the uterus has been cut open so that we could see inside details and there are three main regions in the uterus the fundus the body and the cervix the fundus is the superior part followed by the body and then the cervix now the cervix has a couple key areas if we look at the cervix through the vaginal canal we see that at the entrance of the cervix there is an opening called external Oz which then leads into the cervical canal and then into the internals which is deeper within the body of the uterus the external Oz is the external orifice of the cervix and it is what is checked for dilation during childbirth now cervical cells are the ones that are scraped and tested for cancer of the cervix and this is the famous pap smear the named pap is short for dr. Papanicolaou the gynecologist who developed this method of inserting a cotton swab through the vaginal canal and gently scraping cells of the cervix and then sending these cells to a lab to be checked if they appear to be precancerous or cancers now the cervical canal is typically plugged with mucus and that mucus serves as a protective barrier against bacteria that could possibly enter the uterus through the vaginal canal now lining the inside of the uterus body we find the endometrium and the endometrium is what changes in thickness to prepare for pregnancy the uterus and the medium is the site of implantation of the fertilized egg and blood vessels found within the endometrium can actually nourish the fertilized egg now if the woman is not pregnant the endometrium is what sheds off when the woman has a period deep to the endometrium we find the myometrium and there Myo means muscle right so the myometrium is this thick layer of smooth muscle and since it is take it protects the developing embryo from the surrounding bony structure of the pelvic cavity also as always most muscles in our body the myometrium is under involuntary control so it's under the control of the autonomic nervous system as well as hormonal factors like oxytocin and this is most muscle layer is what contracts and forces the fetus out during labor outside of the uterus we find the pairing medium which is a thick connective tissue that is involved with protecting the uterus itself if we zoom in into the endometrium we see that the endometrium is composed of a simple columnar epithelium with underlying functional layer and then a basal layer as well as uterine glands that open up to the uterus lumen the basal layer of the endometrium is the deeper layer that's adjacent to the myometrium or the smooth muscle of the uterus the basal layer doesn't really change much during a normal uterine cycle and when we talk about how the endometrium grows and sheds over the course of a uterine cycle we are actually talking about the functional layer of the endometrium the functional layer of the endometrium is the one that grows and sheds with normal uterine cycles so this functional layer is what lines the lumen of the uterus and it changes in thickness during normal uterine cycle it will shed during the menstruation frays and regrow later on the significance of menstruation is to shed off the functional layer of the endometrium and then it regrows so basically the tissue is always fresh with new blood vessels in new epithelium and that's more hospitable for the implantation of a fertilized egg for the implantation of an embryo so then the medium and sheds we think every 28-day cycle in this continues throughout the female reproductive years now the shedding of the endometrium actually happens because the blood vessels that grow they constrict and they're vasoconstriction prevents nutrients and oxygen from getting into the endometrial tissue and if you're not giving oxygen in nutrients to a tissue the tissue dies and that's what actually happens to the functional layer of the endometrium it dies and it begins to shed off and as it sheds it leaves behind broken blood vessels and those broken blood vessels begin to bleed in thats called having a period so that's called menstruation so the uterine cycle is a description of the repeating series of change in the endometrium and it starts at the menarche which is the very first period until the menopause which is the last period now the uterine or menstrual cycle has three main phases the menstrual phase the proliferative phase and the secretory phase now as you can see the uterine cycle is also called menstrual cycle and the reason for that is because the first phase is the menstrual phase so keep that in mind now all these phases are influenced by hormonal factors they are under the influence of estrogen and progesterone secreted by the ovary so changing hormone concentrations that correlate with the development of the ovarian follicle is what actually influence the menstrual phase the proliferative phase and the secretory phase so the uterine cycle begins with the menstrual phase in this phase is characterized by the menses or menstruation and menstruation is the actual process of bleeding menstruation lasts from 1 to 7 days and during this period a woman can lose anywhere between 1.2 to 1.7 ounces of blood now the pain that associated with menstruation is because the uterus is contracting so the myometrium of the uterus contracts and these contractions is the uterus attempt to remove all the extra tissue and blood that's not needed so the contractions help to lose the blood and tissue more efficiently now after menstruation so after all the blood is lost then we have what's called the proliferative phase and that is when the rebuild of the endometrium begins so the functional layer of the endometrium is starts to proliferate hence the name proliferative phase after the proliferative phase there is the secretory phase and this is the phase where the endometrium is added stickers and there is lots of blood vessels and lots of mucus being secreted by the uterine glands hence the name secretory phase so during this phase then the medium is being prepared to receive a fertilized egg the endometrium is getting ready for implantation so when the uterus is going through menstruation the lumen of the uterus is pretty empty the endometrium is very thin because it is shedding as soon as menstruation is over then the proliferative phase begins and that marks the rebuild of the endometrial tissue the secretory phase is when the endometrium grows even thicker and that's all in preparation for pregnancy and when the secretory phase is over if the woman did not get pregnant then the cycle starts again with the woman having a period menstruation here we have a parallel of what happens in the ovarian cycle and what happens in the uterine cycle so the ovarian cycle is far today zero with the spike of the follicular stimulating hormone in this hormone is released by the pituitary gland into the bloodstream when the follicular stimulating hormone FSH reads the ovaries that stimulates the primordial follicle to start to grow and the growing of the primordial follicle leads to the release of estrogen into the bloodstream now what's very interesting is that as the primordial follicle as the follicle develops the follicle gets larger and larger and larger and the larger the follicle is the more estrogen it releases into the bloodstream and when the estrogen levels reach a certain amount a certain concentration in the bloodstream that stimulates the proliferative phase of the endometrium so when the estrogen in the bloodstream reaches the uterus the endometrium of the uterus starts to regrow due to the estrogen that is being released by the follicles that are being developed in the ovary now when the estrogen levels are very high that is stimulates the pituitary gland to release another hormone called luteinizing hormone and I spiked off the luteinizing hormone leads to the ovulation so the egg is released is popped out of the ovary the ovulation happens at day 14 of the ovarian cycle and at the same time the ovulation happens that when the secretory phase of the uterine cycle starts because now there is an egg that can possibly get fertilized and in case there gets fertilized and the medium needs to be ready to handle an implantation so the secretory phase of the uterine cycle starts when ovulation happens in the over and the secretory phase is marked by the growth the thickening of the endometrium the growth of blood vessels and the growth of uterine glands that secretes lots of mucus into the lumen of the uterus now once the inter seen is that when ovulation happens the follicular cells that were left behind we think the ovary they become they turn into corpus luteum and when this cells torn into corpus luteum when they are stimulated by the luteinizing hormone LH hormone they secrete lots of progesterone and some estrogen but the point is that these cells they secrete progesterone and progesterone is the hormone that as the name says it prepares the body for pregnancy so prou is something that comes before ingestion you have the root jest which means gestation in gestation is pregnancy so progesterone is the hormone that prepares the body for pregnancy and progesterone released by the corpus luteum is what goes to the endometrium and it stimulates the endometrium to grow even further to grow very thick and with lots of blood vessels and lots of mucus to receive the possible fertilized egg and then is the secretory phase of the uterine cycle so as you can see here at day 14 ovulation happens and then for the next two weeks for the following 14 days we have the endometrium the functional layer of the endometrium growing even thicker and that's the secretory phase now what happens is that if the egg does not get fertilized the corpus luteum turns into corpus albicans in the turning of the corpus luteum into corpus albicans each one marks the end of the ovarian cycle and then if the corpus albicans is basically scar tissue that we mentioned before so it's dead corpus luteum cells dead cells cannot secrete lots of hormones and consequently projects levels will drop dramatically now if progesterone levels drop there is no a stimulus for the endometrium functional layer to keep growing and with that the secretory phase ends and then the menstrual phase begins in the menstrual phase starts because of the draw of the hormone levels in the bloodstream because there was nothing is stimulating the endometrium to keep growing so if we do not have any stimulation we have the endometrium that was prepared for pregnancy being shared out and then all that extra tissue is removed because there is no need for it now under the cervix we see the vaginal canal in these edges of the cervix that is in contact with the vaginal canal and goes a little up that's what I call vaginal fornix the vagina is an elastic muscular tube that connects the uterus in the outside of the body the vaginas major functions are passageway for elimination of menstruation fluid receiving the penis during sexual intercourse and forming the inferior portion of the birth canal now the vagina has its normal population of bacteria in the cervical mucus is what provides the nutrients that keep this bacteria alive this bacteria has a protective role because the bacterial metabolism creates an acidic environment in the acidity reduces the growth of pathogens but it also reduces the mobility of this firm and if you recall when we talked about the semen we said that the semen the seminal fluid that the sperm is kept was basic and that helped to neutralize the acidity of the male urethra and it also helped neutralize the acidity of the vagina and here it is now the law of the vagina is made of non-keratinized stratified squamous epithelium we to make sense because it stratified means it has several layers of cells so it is thick it is tough and it's highly resistant to abrasion when this stratified squamous tissue is relaxed the vagina has these wrinkles that we name roogie now they are opening of the vagina is the vaginal orifice and in girls there is this thin layer of tissue that completely or partially covers the vaginal orifice and this thin layer of tissue is called hymen the first time the hymen is broken there is a little bit of bleeding in a little bit of pain now the breaking of the hymen can occur with the first sexual intercourse or it's possible that the hymen is broken because of physical activity before the first sexual intercourse the female genital area is called vulva involving is basically all these things that we are seeing here combined so it includes the vestibule the lobby majora lobby a menorah and the clitoris the labia majora is this thing skin with hair and as I mentioned before the lobby majora is homologous to the male scrotum and it's effectively the same kind of tissue it is thin skin with her now medial to the lobby of majora we find the lobby menorah in the lobby Emine hora is thick skin and it doesn't have hair in it the space between the labia minora is called the vestibule and within the vestibule we find the vaginal orifice in the urethral opening just to the vaginal orifice now on each side of the vaginal entrance we find the bulb of the vestibule and what you need to remember is that the bulb of the vestibule is homologous to the Mayo corpus spongiosum and posterior to the bulb of the vestibule which is equivalent to the Mayo corpus spongiosum we find the greater vestibular gland which is homologous to their Bobo you literal glance in males in like the Bobo redraw glands in males the greater vestibular glands produce a new cassava lubricant during sexual excitement the clitoris is equivalent the corpus cavernosum in males in like the corpus cavernosum emails the clitoris is essentially the female erectile tissue that gets engorged with blood during sexual excitement basically the clitoris is the female version of the penis in like the penis the clitoris has a cap called glands and also like in males the clitoris has a prepuce around it the clitoris prepuce is found where the Chula BIA menorah meet anteriorly in forms like a hood covering the clitoris just like the prepuce on the penis now in terms of structure of the breasts we see the nipple and surrounding the nipple we find the areola this pinkish Brown pigmented ring surrounding the nipple around the areola we do find hair so there is hairy skin and also we find glands that are associated with body odor glands that are associated with zero mono communication within the breasts we find mammary glands and mammary glands are responsible for producing milk that serves as nutrition for infants the mammary gland is divided into lobes which are divided into lobbyists the lobbyists produce milk under hormonal stimulus when milk is produced milk drains into the lactiferous ducts and as the lactiferous ducts approach the nipple it becomes like tea for sinus so a little wider right so the nipple is actually the exit point of these lactiferous sinus one of the hormones that can stimulate production of milk is prolactin but a different hormone stimulates the secret of milk from the nipple and that hormone is oxytocin oxytocin is the same hormone that stimulates uterine contractions so while you're breastfeeding the uterus is also contracting because the hormone that stimulates the secretion of milk from the nipple is the same hormone that stimulates uterine contractions breast milk is mostly water some proteins sugar and fats and it is involved in nourishment right and there is some evidence that suggests is that women who breastfeed are less likely to develop breast cancer and what's very interesting is that woman that breastfed with only one breast only one of the two breasts they are more likely to develop breast cancer in the breast that was not used to breastfeed now the whole breast is supported by suspensory ligaments which are broad bands of connective tissue and as you can see here most of the breast structure is actually adipose tissue in adipose tissue doesn't have much of a structure so what kind of shapes and positions the entire breast is this suspensory ligament basically the suspensory ligaments incurred the mammary glands to the underlying pectoralis major muscle and with that the suspensory ligaments hold the breasts in place now the last thing you need to talk about is the parasympathetic stimulation during female sexual arousal and it's very similar to what happen in males but in females the parasympathetic stimulation causes clitoral erection it causes the vagina to get moist and and it causes engorgement of blood vessels in the breasts and these can actually cause what some people refer to as sex flush which is the reddening of the chest and with these we finished the female reproductive system please let me know if you have any questions see you in class I