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The Menstrual Cycle Yeovil Fertility Unit The Menstrual Cycle Yeovil Fertility Unit Yeovil District Hospital NHS Foundation Trust Higher Kingston Yeovil Somerset BA21 4AT Ref: 14-16-153 01935 475 122 Review date: 06/18 yeovilhospital.nhs.uk The menstrual cycle is the process Ovulation controlled by hormones, during which Oestrogen levels that have been gradually an egg develops and is released from increasing, peak. The LH levels increase the ovaries and the lining of the uterus rapidly (day 12 onwards) triggering the Follicle Ovulation Corpus (endometrium) thickens in preparation development luteum release of the egg from the ripened follicle, for a possible pregnancy. which usually occurs 36 hours after the onset of the LH surge. A female is born with thousands of egg cells (follicles) which lie dormant in the The luteal phase ovaries until puberty when rising The levels of FSH and LH decrease. The hormones lead to the maturation of Endometrium ruptured follicle closes (after releasing the several follicles a month. egg) and forms a corpus luteum, which produces progesterone. This prepares the The menstrual cycle is under the endometrium even further, ensuring it is control of three sets of hormones: spongy, thick and full of nutrients so that a fertilised egg can implant into it. If the egg Gonadotrophin releasing hormones is not fertilised the corpus luteum starts to Flow Follicular phase Luteal phase Gonadotrophins - luteinising hormone phase degenerate and progesterone and (LH) and follicle stimulating hormone 1 5 14 28 oestrogen levels start to fall. (FSH) from the pituitary gland Ovarian hormones - oestrogen and Ovulatory phase The endometrial blood vessels constrict progesterone and the endometrium breaks down and is shed as a period (menstruation). The menstrual cycle can be divided into The Menstrual Cycle three phases: The length of the follicular phase can vary between women. However, the duration of The follicular phase the luteal phase is fairly constant, being 14 FSH stimulates the development of several days in most women. The first day of the follicles in the ovary, usually only one of period is counted as day one of the cycle. these follicles matures. This dominant The cycle runs from the first day of follicle produces oestrogen, which causes menstruation to the next first day. the endometrium to start to thicken. It also causes the mucus in the cervix to become thinner and more stretchy, allowing sperm to reach the egg more easily. The menstrual cycle is the process Ovulation controlled by hormones, during which Oestrogen levels that have been gradually an egg develops and is released from increasing, peak. The LH levels increase the ovaries and the lining of the uterus rapidly (day 12 onwards) triggering the Follicle Ovulation Corpus (endometrium) thickens in preparation development luteum release of the egg from the ripened follicle, for a possible pregnancy. which usually occurs 36 hours after the onset of the LH surge. A female is born with thousands of egg cells (follicles) which lie dormant in the The luteal phase ovaries until puberty when rising The levels of FSH and LH decrease. The hormones lead to the maturation of Endometrium ruptured follicle closes (after releasing the several follicles a month. egg) and forms a corpus luteum, which produces progesterone. This prepares the The menstrual cycle is under the endometrium even further, ensuring it is control of three sets of hormones: spongy, thick and full of nutrients so that a fertilised egg can implant into it. If the egg Gonadotrophin releasing hormones is not fertilised the corpus luteum starts to Flow Follicular phase Luteal phase Gonadotrophins - luteinising hormone phase degenerate and progesterone and (LH) and follicle stimulating hormone 1 5 14 28 oestrogen levels start to fall. (FSH) from the pituitary gland Ovarian hormones - oestrogen and Ovulatory phase The endometrial blood vessels constrict progesterone and the endometrium breaks down and is shed as a period (menstruation). The menstrual cycle can be divided into The Menstrual Cycle three phases: The length of the follicular phase can vary between women. However, the duration of The follicular phase the luteal phase is fairly constant, being 14 FSH stimulates the development of several days in most women. The first day of the follicles in the ovary, usually only one of period is counted as day one of the cycle. these follicles matures. This dominant The cycle runs from the first day of follicle produces oestrogen, which causes menstruation to the next first day. the endometrium to start to thicken. It also causes the mucus in the cervix to become thinner and more stretchy, allowing sperm to reach the egg more easily. The menstrual cycle is the process Ovulation controlled by hormones, during which Oestrogen levels that have been gradually an egg develops and is released from increasing, peak. The LH levels increase the ovaries and the lining of the uterus rapidly (day 12 onwards) triggering the Follicle Ovulation Corpus (endometrium) thickens in preparation development luteum release of the egg from the ripened follicle, for a possible pregnancy. which usually occurs 36 hours after the onset of the LH surge. A female is born with thousands of egg cells (follicles) which lie dormant in the The luteal phase ovaries until puberty when rising The levels of FSH and LH decrease. The hormones lead to the maturation of Endometrium ruptured follicle closes (after releasing the several follicles a month. egg) and forms a corpus luteum, which produces progesterone. This prepares the The menstrual cycle is under the endometrium even further, ensuring it is control of three sets of hormones: spongy, thick and full of nutrients so that a fertilised egg can implant into it. If the egg Gonadotrophin releasing hormones is not fertilised the corpus luteum starts to Flow Follicular phase Luteal phase Gonadotrophins - luteinising hormone phase degenerate and progesterone and (LH) and follicle stimulating hormone 1 5 14 28 oestrogen levels start to fall. (FSH) from the pituitary gland Ovarian hormones - oestrogen and Ovulatory phase The endometrial blood vessels constrict progesterone and the endometrium breaks down and is shed as a period (menstruation). The menstrual cycle can be divided into The Menstrual Cycle three phases: The length of the follicular phase can vary between women. However, the duration of The follicular phase the luteal phase is fairly constant, being 14 FSH stimulates the development of several days in most women. The first day of the follicles in the ovary, usually only one of period is counted as day one of the cycle. these follicles matures. This dominant The cycle runs from the first day of follicle produces oestrogen, which causes menstruation to the next first day. the endometrium to start to thicken. It also causes the mucus in the cervix to become thinner and more stretchy, allowing sperm to reach the egg more easily. The Menstrual Cycle Yeovil Fertility Unit Yeovil District Hospital NHS Foundation Trust Higher Kingston Yeovil Somerset BA21 4AT Ref: 14-16-153 01935 475 122 Review date: 06/18 yeovilhospital.nhs.uk.
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