Menstrual Cycle Oral Contraceptives

gentlemen welcome back to another chapter in physiology I'm your host al-assad and today we have an interesting subject of the female menstrual cycle now this is somewhat complicated amongst medical students but we're here to uncomplicate things okay let's start with some basics now the manners to cycle basically it's a cycle so has to have this start point and going on to an end point ok so what is the first event in the miniature cycle well since it's called the menstrual cycle so clearly enough menses or bleeding so starts with menses keeps on going until it also ends with menses where the other cycle starts now during this cycle there's a very important event happening and we all need to know this which is ovulation that's when the ovum leaves it leaves the ovary and waits for the sperm so I can get fertilized ok on the side between you know before the ovulation after ovulation there are two phases the first phase over here what we call the follicular phase why is it called follicular phase because it's when the follicle which contains the oocyte develops and then when once the follicle bursts it will give us the oocyte the remnant of the follicle will give us something called the corpus luteum so this will give us here the luteal phase ok all these details I don't need to know I just need to know that the folic follicular phase and luteal phase okay let's talk time duration the luteal phase takes about approximately 14 days okay this is fixed all female huh all females have a 14-day luteal phase what about the follicular phase well approximately it takes about well know knows how much it takes but somewhat in the range of 14 days that's why you have females with a 28-day cycle some of them have a 30-day cycle some of them have a 32 they cycle why because they differ and the follicular phase okay now what we said is the important part to know is ovulation when does ovulation happen well let's say we have a female with a 30-day cycle 30-day thirtieth day will be approximately over here now if you want to know when's ovulation which is over here we do what we do we just subtract 14 so 30 minus 14 equals 16 over here okay so it's kind of ugly she will happen on the 16th day then the female knows when the ovulation will happen and therefore can schedule times of sexual intercourse so fertilization can happen since we said do we have follicular phase and a luteal phase let's talk in to hormones now the follicular phase has a hormone which is dominant which is the estrogen however the luteal phase has progesterone now what do these hormones do well since we just had menses okay so big chunk of the endometrium just fell off just let exit the body so we need that chunk to grow back again we need the endometrium of the uterus to grow back again so estrogen will give us proliferation of cells in the endometrium okay so it will make the endometrium grow bigger very important however the progesterone or what will it do well what happened before producer we had ovulation so let's say we had fertilization and we want pregnancy to happen this will go to the uterus but it needs to have a good atmosphere an atmosphere of an endometrium full of secretions so progesterone will start the secretions or make the endometrium all more secretory so a lot of secretions will happen other in other words they'll make the endometrium more juicy okay so let's just revise what we just said here so we have the first number-one thing you need to know first event of the menstrual cycle is menses okay we have two phases follicular phase and luteal phase the follicular phase is the phase variable okay which phase variable on the killer phase very good to know how do we know when's ovulation we take the number the days of the cycle we just subtract 14 which is the days of the luteal phase and that will give us a diesel cycle follicular phase has estrogen which gives us proliferation of cells and the luteal phase has progesterone which will give us secretion will give us a juicy endometrium okay let's jump to the next slide now follicular phase first about first two weeks you know most women have it about 14 days or said it's variable okay we said it has estrogen and estrogen gives us endometrial proliferation okay after that we're going to have up ovulation approximately day 14 because usually women have a 28-day cycle that's what you'll read in books mostly before ovulation we'll have something called LH surge we'll explain that later after that we have luteal phase which is 14 days this is what we said this is fixed can't change won't change okay and in dilute your face the dominant hormone is progesterone will give us a secretory endometrium because we need a good atmosphere for pregnancy to happen and then we're gonna have menses which will start the next cycle okay here's oh here's a note we mentioned before total cycle length minus 14 which is the luteal phase nowadays give us a view Latian okay so let's get into full ocular phase what's exactly going on in follicular phase okay well as you see here we have a lot of primary follicles primary follicles a lot of them over here okay we want one of them to grow and give us a site okay well one of them to keep on growing so it's growing over here going over here and here and here until it grows big enough where the O site bursts out this is ovulation over here this one this phase over here is ovulation okay so what stimulates a follicle to grow well what better thing to stimulate it then a follicular stimulating hormone so FSH you remember that hormone from the pituitary it will come in start and do sink growth okay so you see here we have three follicles actually we can have a lot of follicles but what all of them are going to die except for one this big one is going to grow why does this happen and how does this happen nobody knows which is good news for us so here in a kind of follicle we have two main cells granulosa cells and fika cells okay these are important we're going to take let's take a closer look about what's going on over there but before we go there okay just give you a point but after here when you see ovulation happens what happens to the follicle it becomes a corpus luteum okay put that in red because it's important corpus luteum this is when the luteal phase starts right over here in red okay these are this is the luteal phase over here so let's now let's just go and let's zoom in to this to this section so you can see what's going on okay so as you see here we have FSH we said we have granulosa cells and we have theca cells and you have here over your LH okay so what's going to happen election FSH are going to work together LH will give us androgens will stimulate the theca cells to give us androgens and as we said in previous chapters and per chapter of adrenal gland the androgens are the precursor for testosterone estrogen and whatnot so here Sika cells will give us androgens this will move to the granulosa cells and will give us a sturgeon okay now what will estrogen do basically what estrogen will do will give a negative feedback to FSH and LH okay negative feedback let's repeat again what's what's going on okay it's just a little bit revision before we go to the next slide LH and FSH are going to work LH will work on fika cells give us androgens okay androgens are gonna go to the granulosa cells and that green load cells are going to turn androids into estrogen why because it has a very important enzyme which is aroma taste okay aroma taste will give us to using this enzyme will give us estrogen Astral have a negative feedback on FSH and LH so follicular follicular phase we said menses is the first day of the cycle we said we had high FSH okay high FSH will give us more estrogen secretion that's when we said the full the follicles give us estrogen Zika cells make androgens granulosa cells make estrogen using which enzyme aroma taste aroma tea is very important to know this enzyme okay that estrogen has what's function of estrogen we said before and remission proliferation okay we have secondary sexual characteristics as you can see here and of course cervical mucus becomes thin and watery why do we need this so sperm can swim even easier okay we need those we need Sprint swim more easier so I can go and fertilize the Oh site so we said here that we're going to have estrogen as estrogen and orange juice if you have estrogen and blue we have our LH and then purple have FSH so as you can see here we said that FSH will first grow up go up and stimulate estrogen to go estrogen will have a negative feedback that's why FSH is going down as you can see here negative feedback but however it will reach a point over here when it's high enough what you can see something something's going wrong because LH and FSH are supposed to go down but wait a second they're going up that's not supposed to happen what's what's going on okay well this is one of the complicated things in the minister cycle which we don't know why it happens but it happens this is the same picture as last time however there's two things that that changed no longer negative feedback suddenly it turned into positive feedback how did that happen we don't know it's just that at a certain point when estrogen becomes high enough in the body it turns the negative feedback into positive feedback so we're going to have more estrogen so more estrogen means more FSH more LH that will give us more antigens and more estrogen and it's cycle keeps on going on keeps on going on until ovulation happens so so I'll go back a couple slide over here so once estrogen goes up to a certain level as we said here it's high enough to give us positive feedback okay it will keep on going high keep on going high and keep on going high until it Peaks once it Peaks and begins to go down then we have something over here in the LH what we call the LH surge once you have LH surge we have ovulation that's a very important exam question okay what's the vent that happens before ovulation or what's the event that induces ovulation LH surge okay however there is a very important rule for LX surge to happen we need the estrogen to peak and start to go down if it doesn't peak and keeps on going up no LH surge no allege surge no ovulation okay so when estrogen rises to a certain level they begin to stimulate the secretion of LH and FSH we have positive feedback negative feedback becomes positive feedback okay then we have LH surge which will give us a violation okay it happens when estrogen Peaks so it has to start to go down because it peaked and starts to go down if he keeps on going up no ovulation okay so LH removes the restraint upon meiosis completion of first meiotic division and release of the first polar body so before or exam question usually one does the first meiotic division finishes at the point of ovulation you know before ovulation just before the oocyte leaves the follicle that's when the first meiotic division happens and we release the first body so these two things we need to you need to know because it might come in an exam question as when does the first meiotic division happen in the female matter cycle or when does the first polar body gets released okay so now we have the luteal phase okay after the alleged surge the follicle turns into a corpus luteum as we said last time which will give us what's the main hormone progesterone a little bit of estrogen but mostly most important is progesterone okay so we have high LH right which gives us what your school stimulate the corpus luteum to function and give us progesterone producer will have a negative feedback on LH just like estrogen hat in the follicular phase at the beginning of the follicular phase okay so what will progesterone do we said it will give us a juicy endometrium it will give give us basic cervical mucus and the body temperature will increase why the why the body temperature increase I have no idea or most likely no one has no idea the cervical mucus becomes thick just to prevent any more sperm to come in or any kind of organisms to come in because at this point in the luteal phase ovulation already happened so as another way sperm you already had your chance you lost it okay so here this is the luteal phase as you can see the this section over here the post ovulation after ovulation we have blue to your face okay now as you can see here we have the LH is high over here the LH is high so it will give us the corpus luteum will start giving us four just thrown and as you said a little bit of estrogen will give us a negative feedback on the LH so now the corpus luteum will start to survive over here as you can see here the corpus luteum okay until what happens it dies it expires just like milk in the fridge okay it's going to expire at some point and once it expires no more progesterone progesterone will fall down okay and then a surgeon will fall down what's Wow so why do we need to know this because once progesterone and estrogen fall down what will happen whole endometrium which is cue big and thick and juicy will all collapse so exam question what do we need for to preserve the endometrial wall progesterone estrogen why do they fall because we lost these hormones we said that in the first slide but we think even much attention because I was going to explain right here so for just Iran and estrogen are the ones that maintain the endometrial wall once they fall down because of the corpuscle team just expired we have menses once you have menses we start another cycle and you however let's say fertilization happened okay let's just say we had a fertilization first of all where does that fertilization happen very important very poor this is a definitely exam question over here where does fertilizing happen this is you can guarantee it on your exam okay now what happens if fertilization goes on let's just let's just take a look so once you have an O site in the fallopian tube which is in the ampulla waiting it gets fertilized by sperm okay once you get fertilized it will start to swim to the endometrium okay as you can see here day fourteen to day fifteen is ovulation day fifteen fertilization day fifteen to twenty it will be swimming and swimming and swimming until it implants and it plants in the endometrium after that it will at day 25 well look what will give us give us a very important hormone beta HCG beta HCG what will this do this will act like what LH it will act like a ll H it will pretend it's LH so what did you say LH does it gives us high progesterone and estrogen so once we have high progesterone high as usual well what are we preventing we are preventing the endometrial wall of collapsing basically so that pregnancy will go on okay pregnancy keep on going on okay so that's that's basically a fertilization another important point we have to mention the second meiotic division happens in fertilization what when did we said the first one finishes the first one finishes during before right at a Latian before before the o'the site leaves the corp the fault of the follicle that's when the first mark division happens exam question might come in when does the second meiotic division happen well that will happen during at fertilization okay oral contraceptives this is a very important drug you need to know okay so oral contraceptives the most common are a combination of estrogen and progestin s' or position adjust a synthetic word for progesterone okay so progestins they suppress the mid-cycle LH surge if we don't have a lesser jewel we don't have we don't have ovulated oral contraceptives are made so you don't have pregnancies okay so if we have progestin or progesterone this will suppress the mid cycle LH surge what about estrogen estrogen will suppress FSH if you don't have FSH no follicle will grow if no follicle will grow no sight okay plus helps us with some of the side effects of the progestins okay now decrease effectiveness and matter with mic antimicrobial and enzyme inducers so some antimicrobial drugs and enzyme inducers decrease the effectiveness of oral contraceptives there's important part I need to explain here which is anti epileptic drugs anti peptic drugs most of them are enzyme inducers antiepileptic drugs okay so except now if we have for example a question twenty thirty year old female who's taking oral contraceptives and has epilepsy you want to prescribe an antiepileptic drug tumor which drug is most applicable for this patient the answer is a pro acid okay a pro acid it's the one that does not does not affect the oral contraceptives okay so what are the functions of the oral contraceptives it regulates the medicine cycle okay they said regulate sometimes he actually uses it's used to regulate events like what females have have a disturbed minister cycle some of them use it for regulation of that's just like okay and of course we it's oral contraceptives so it prevents pregnancies okay it also has a lot of benefits decreased risk of endometrial and ovarian cancer and also decrease osteoporosis okay but these are not not as important as the number the most to uses or the most to functions of oral contraceptives is one to prevent pregnancy and to what regulate cycle okay side-effects this lobe just won't take much time okay weight gain high LDL in the ones you see in red is the reasons why someone might stop oral contraceptives if you increases blood pressure you might stop it deep vein thrombosis could cause clots abnormal liver biochem migraines depression these are the things that people come in and say hey doctor I'm having one of these symptoms and my cause might be the gall conscience is you might have to stop the core concepts because of these symptoms okay it caused liver adenoma a good thing about liver adenoma is that once you stop the oral contraceptives it will go away will start to reduce and go away okay and that's all the time I have and thank you everyone