Jennifer Knudtson

, MD, college of Texas wellness Science center at mountain Antonio;

Jessica E. McLaughlin

, MD, medical University of southern Carolina





Menstruation is the shedding that the lining the the uterus (endometrium) attach by bleeding. It occurs in about monthly cycles throughout a woman"s reproductive life, except throughout pregnancy. Menstruation starts during puberty Puberty in girls Puberty is a succession of events in i m sorry physical transforms occur, causing adult physics characteristics and also capacity to reproduce. This physical transforms are regulated by transforms in the... read more (at menarche) and also stops permanently in ~ menopause Menopause Menopause is the permanent end of menstrual periods and also thus of fertility. For up to numerous years before and also just after menopause, estrogen levels fluctuate widely, periods come to be irregular... read much more


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By definition, the term cycle starts with the an initial day of bleeding, which is counted as day 1. The cycle ends just prior to the following menstrual period. Expression cycles normally variety from around 25 come 36 days. Only 10 come 15% the women have actually cycles the are specifically 28 days. Also, in at least 20% the women, cycles are irregular. The is, castle are longer or much shorter than the typical range. Usually, the cycles differ the most and the intervals between periods are longest in the years instantly after menstruation beginning (menarche) and also before menopause.

Menstrual bleeding big 3 to 7 days, averaging 5 days. Blood loss throughout a bike usually varieties from 1/2 to 2 1/2 ounces. A restroom pad or tampon, depending on the type, can hold up to an oz of blood. Menstrual blood, unequal blood result from an injury, typically does not clot uneven the bleeding is an extremely heavy.

The menstrual bicycle is regulation by hormones. Luteinizing hormone and also follicle-stimulating hormone, i beg your pardon are produced by the pituitary gland, encourage ovulation and stimulate the ovaries to create estrogen and also progesterone. Estrogen and also progesterone stimulate the uterus and breasts come prepare for feasible fertilization.


The menstrual bike is regulated by the complex interaction the hormones: luteinizing hormone, follicle-stimulating hormone, and also the female sex hormones estrogen and also progesterone.

The menstrual cycle begins with expression bleeding (menstruation), which marks the first day of the follicular phase.

When the follicular phase begins, level of estrogen and progesterone room low. Together a result, the top layers of the thickened lining the the uterus (endometrium) breakdown and are shed, and menstrual bleeding occurs. About this time, the follicle-stimulating hormone level rises slightly, stimulating the advancement of number of follicles in the ovaries. Every follicle includes an egg. Later in this phase, together the follicle-stimulating hormone level decreases, just one follicle continues to develop. This follicle produce estrogen.

The ovulatory phase begins with a surging in luteinizing hormone and also follicle-stimulating hormone levels. Luteinizing hormone stimulates egg relax (ovulation), which commonly occurs 16 to 32 hrs after the surge begins. The estrogen level decreases throughout the surge, and the progesterone level starts come increase.

During the luteal phase, luteinizing hormone and follicle-stimulating hormone level decrease. The ruptured follicle closes after releasing the egg and also forms a body luteum, i beg your pardon produces progesterone. Throughout most of this phase, the estrogen level is high. Progesterone and estrogen reason the lining that the uterus to thicken more, come prepare for possible fertilization.

If the egg is no fertilized, the body luteum degenerates and also no longer produces progesterone, the estrogen level decreases, the top layers of the lining failure and room shed, and also menstrual bleeding occurs (the begin of a brand-new menstrual cycle).

If the egg is fertilized, the body luteum proceeds to duty during early on pregnancy. That helps preserve the pregnancy.

The follicular phase starts on the an initial day of expression bleeding (day 1). But the main occasion in this step is the breakthrough of follicles in the ovaries.

At the start of the follicular phase, the lining of the uterus (endometrium) is thick with fluids and also nutrients designed to nourish an embryo. If no egg has been fertilized, estrogen and progesterone levels are low. Together a result, the peak layers the the endometrium space shed, and menstrual bleeding occurs.

About this time, the pituitary gland slightly rises its production of follicle-stimulating hormone. This hormone then stimulates the development of 3 come 30 follicles. Each follicle includes an egg. Later on in the phase, as the level of this hormone decreases, only among these follicles (called the leading follicle) proceeds to grow. The soon begins to create estrogen, and also the other stimulated follicles begin to break down. The increasing estrogen additionally begins come prepare the uterus and also stimulates the luteinizing hormone surge.

On average, the follicular phase lasts about 13 or 14 days. The the 3 phases, this step varies the most in length. It often tends to become shorter near menopause. This phase ends as soon as the level the luteinizing hormone increases substantially (surges). The surge outcomes in relax of the egg (ovulation) and marks the start of the next phase.

The ovulatory phase begins when the level that luteinizing hormone surges. Luteinizing hormone stimulates the leading follicle to bulge indigenous the surface ar of the ovary and finally rupture, release the egg. The level of follicle-stimulating hormone increases to a lesser degree. The function of the rise in follicle-stimulating hormone is no understood.

The ovulatory phase commonly lasts 16 come 32 hours. The ends when the egg is released, about 10 to 12 hrs after the surging in the level of luteinizing hormone. The egg deserve to be fertilized for only up to around 12 hours after the release.

The surging in luteinizing hormone deserve to be detect by measure up the level the this hormone in urine. This measurement have the right to be supplied to identify when women room fertile. Fertilization is an ext likely when sperm are present in the reproductive tract prior to the egg is released. Many pregnancies occur when intercourse occurs in ~ 3 days prior to ovulation.

Around the moment of ovulation, some ladies feel a dull ache on one side of the reduced abdomen. This pain is recognized as mittelschmerz (literally, middle pain). The pain might last for a couple of minutes come a couple of hours. The pain is generally felt top top the same side as the ovary that released the egg, however the specific cause of the pains is unknown. The pain may precede or follow the rupture of the follicle and also may not happen in every cycles.

Egg relax does not alternative between the two ovaries and also appears to be random. If one ovary is removed, the remaining ovary publication an egg every month.

The luteal phase begins after ovulation. The lasts around 14 days (unless fertilization occurs) and ends just prior to a term period.

In this phase, the ruptured follicle close the door after releasing the egg and forms a structure called a corpus luteum, i beg your pardon produces raising quantities that progesterone. The progesterone developed by the body luteum walk the following:

throughout most of the luteal phase, the estrogen level is high. Estrogen additionally stimulates the endometrium to thicken.

The increase in estrogen and also progesterone levels causes milk ducts in the breasts come widen (dilate). Together a result, the breasts might swell and also become tender.

If the egg is not fertilized or if the fertilized egg does no implant, the body luteum degenerates after ~ 14 days, level of estrogen and also progesterone decrease, and a new menstrual cycle begins.

If the embryo is implanted, the cells around the occurring embryo start to create a hormone dubbed human chorionic gonadotropin. This hormone maintains the corpus luteum, which proceeds to produce progesterone, until the farming fetus can create its own hormones. Pregnant tests are based upon detecting an increase in the person chorionic gonadotropin level.

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A breast lump (mass) is a thickening or bump the feels different from bordering breast tissue. I beg your pardon of the adhering to statements about breast lumps is no correct?
chest lumps space usually cancer breast lumps may be attach by nipple discharge chest lumps might be fluid-filled bag (cysts) or solid masses chest lumps may be painless or ache

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