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menstrual cycle change from 28 to 21 days

A 41-year-old female asked:
Dr. Philip Miller
46 years experience Family Medicine
Cycle changes: vary with age,hormonal levles, infection, stress, tension anxiety and metabolic illness. Get checked by your GYN.
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A 38-year-old member asked:
Dr. William Brown
43 years experience Gynecology
Not to worry: If your cycles are regular, even as far apart as 40 days, i would not be concerned unless you are attempting pregnancy. Since menses represents prior ... Read More
A 29-year-old female asked:
Dr. Dennis Higginbotham
29 years experience Obstetrics and Gynecology
Probably not: Most women have cycles that remain about the same, but the cycles can change over time. The normal cycle length varies from about 21 to about 36 days ... Read More
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A female asked:
Dr. Audrey Lance
13 years experience Gynecology
Normal: Not every month has the same number of days, and not every period has th exact same number of days in between. To calculate when you will get your nex ... Read More
A 47-year-old member asked:
Dr. Karen Jones
36 years experience Obstetrics and Gynecology
Hormone changes: Hormones become less regular causing cycle to be more irregular. This can be related to stress, eating too much soy, gaining or losing weight, having ... Read More
A 23-year-old female asked:
Dr. Vahe Yetimyan
50 years experience General Practice
Yes.: Although the average cycle is 28 days, it is normal to have a cycle that is shorter or longer.
A 41-year-old female asked:
Dr. Jeff Livingston
21 years experience Obstetrics and Gynecology
Ovulation: Slight changes in the cycle do not matter. You will need to determine if you are ovulating or not. Regular cycles like this usually indicate ovulation ... Read More
A 44-year-old female asked:
Dr. Robert Killian
27 years experience General Practice
Not the way it works: Nope. Ovulation occurs just shy of half way through your cycle. Day 21 would not give the body time to prepare and slough off the uterine lining if n ... Read More
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A 36-year-old female asked:
Dr. Dennis Higginbotham
29 years experience Obstetrics and Gynecology
Yes: If you do not ovulate regularly, then you can frequently skip periods. Sometimes the result is that you will begin to have dysfunctional (frequent ep ... Read More
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A 36-year-old female asked:
Dr. Gurmukh Singh
48 years experience Pathology
Normal variation: What you described falls within the usual variation in cycles. If you had unprotected sex, it would be prudent to repeat the pregnancy test in 4-5 day ... Read More
A 51-year-old female asked:
Dr. Robert Kwok
32 years experience Pediatrics
~June 13 to ~June 23: Approximately june 13-23 would be the fertile days for sex.
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A 42-year-old female asked:
Dr. Walter Evans II
41 years experience Obstetrics and Gynecology
Ask your doctor: fertility drugs frequently affect your menstrual cycle. You may be ovulating earlier. Or you may not be ovulating and just leaving. Your doctor will h ... Read More
A 29-year-old female asked:
Dr. Felecia Sumner
9 years experience Family Medicine
Yes: Yes, depending on your activities, food, stress level, etc, your cycle can change by 2-3 days.
A 24-year-old female asked:
Dr. Robert Killian
27 years experience General Practice
Not enough info: You have not shared enough specific information in your question to give you a valid answer. But, that does not matter. You can verify almost everyth ... Read More
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A 55-year-old member asked:
Dr. Mirela Cernaianu
29 years experience Obstetrics and Gynecology
Perimenopause: When hormones start declining with age the first hormone to decline is progesterone. The periods become shorter and can occur 21days or less from each ... Read More
A 37-year-old member asked:
Dr. Dennis Higginbotham
29 years experience Obstetrics and Gynecology
Natural variation: The nature of the cycle can change with time. What you describe is within normal limits.
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A 27-year-old female asked:
Dr. Anne Phelan-adams
Specializes in Family Medicine
This is a normal &: inevitable. Breast feeding increases prolactin (the hormone that stimulates breast milk production) & suppresses reproductive hormones. As your ba ... Read More
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A 29-year-old female asked:
Dr. Gerard Honore
28 years experience Fertility Medicine
Ovulatory problems: Several possibilities, but most likely an ovulatory problem; i.e. Irregular or skipped ovulations. Thsi can happen with polycistic ovaries, among othe ... Read More
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A 37-year-old female asked:
Dr. Dennis Higginbotham
29 years experience Obstetrics and Gynecology
Normal: 28 to 30 day cycles are the average. The cycles can vary in that range for the same woman from month to month and still be perfectly normal.
A 37-year-old female asked:
Dr. Milton Alvis, jr
40 years experience Preventive Medicine
Longer cycles assoc.: with both metabolic syndrome (both pre & clear Diabetes Mellitus), & polycystic ovarian syndrome, both driven by LFHC foods, eased/relieved by ... Read More
A 26-year-old female asked:
Dr. Douglas Lawson
27 years experience Obstetrics and Gynecology
Bleeding: Not all bleeding is your period. If some of the pregnancy tissue was not extracted during your termination, you may experience prolonged bleeding.
A 46-year-old female asked:
Dr. Joseph Warren
39 years experience Obstetrics and Gynecology
You're ovulating: The regularity of your menses tells me that you are likely ovulating on a regular basis. The amount, and number of days of the menses can vary, even ... Read More
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A 33-year-old female asked:
Dr. Bryan Kurtz
33 years experience Obstetrics and Gynecology
Probably nothing: It's not uncommon for you period to vary if flow on occasion. As long as it was at the right time, you should be ok. If you are concerned about pregna ... Read More
A 46-year-old female asked:
Dr. Charles Whiting
26 years experience Obstetrics and Gynecology
Yes, still possible: A day 21 Progesterone level of 8.7 may mean you didn't ovulate. It is usually over 10 if you ovulated. However, this doesn't always mean you can't g ... Read More

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