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Date of last update: 10/16/2017.

Forum Name: Fertility

Question: late period

 tara storck - Mon Nov 19, 2007 7:25 am

I am a 19 year old female. My period was due november 16th. I have not gotten it yet and I'm getting a little worried. I took plan b early in October and got my period 2 weeks later ( october 16th). Im not sure if i am late because of the pill i took last month or because im pergnant. With my 31 day cycle i believe i was ovulating on the 3rd & 4th of november which i had unprotect sex but i took an at home pregnancy test the day after my missed period and it was negative. Was it to early to detect pregnancy? And when should i test again?
 Debbie Miller, RN - Mon Nov 19, 2007 11:37 am

User avatar Plan B can definitely affect your cycle so perhaps that is the problem. It is also possible that it is too early to detect pregnancy since people vary in the amount of hormone that shows up. If your period doesn't start, I would repeat the test a week after the first. You could also get a serum test (blood) through a doctor's office. These are a little more sensitive.

You might want to consider a hormonal contraceptive for regular use (the pill, patch or shot). It would certainly be better than wondering each time you have sex. For sexually transmitted disease concerns you could also use condoms, but having the hormonal method would give peace of mind about possible pregnancy for the times you might not choose to use those. It is not perfect (no method is) but it is pretty reliable (98-99% effective when used properly).

Good luck.
 tara storck - Mon Nov 19, 2007 11:38 am

since my last post i've done a little more research. I found 2 things. 1- many women who take plan b find their 2nd period after taking the pill to be late. And 2-you are more fertile BEFORE ovulation then during ( I had unprotected sex DURING). So after reading this I figured that it is most likely to be the pill that is causing my period to be late. But this brings me to a new question which I can't seem to get a straight answer to. Will i still ovulate on schedule as if i had gotten my period or lets just say i get my period a week late will it be around 14 days from then? And I also still need to know best time to retest. Thanks!
 tara storck - Mon Nov 19, 2007 12:04 pm

Opps! I guess i posted that second comment just after you read the first. Sorry. As soon as you have the time if you answer the second post it would be great! My mother is a nurse too. I was to afraid to ask her about these things and im really glad this site along with the doctors and nurses are here to help. Im going to tell her about the site to see if she will join! I see how many questions you have answered and i think its absolutly wonder that you are devoting so much of your time to help people for free! I know you don't get very many thank yous for doing this and as thanksgiving is around the conner i thought i would say THANK YOU! And happy thanks giving!
 Debbie Miller, RN - Mon Nov 19, 2007 2:40 pm

User avatar Thanks for your kind words.

The problem is this - only a small percentage of women actually ovulate on the predicted 14th day. We actually refer to a fertile window that comprises several possible days for conception to occur and since you are fertile a few days prior to the actual ovulation, it is very hard to predict. Also, after taking hormonal contraception, it is impossible to say when your next fertile time will be. It would most likely be related to the period, counting from then, but I must emphasize that this is only a guesstimate.

A large study reported in the British Medical Journal found that only 30% of women actually ovulate during this predictable "fertile window." 70% ovulated either before or after this time frame.

So, we can say day 14 is the expected ovulation day, but that is just for convenience in dating pregnancy should it occur - it has little to do with the actual ovulation. That is the reason they have ovulation predictor kits, etc. We just can't reliably count 14 days and call it good. It's kind of a gamble if you use this date to plan a pregnancy or prevent one. It's no more than a likely time, but based on this study, it's probably wrong more often than it is right. It puts you in the ballpark but that's about it.

Let us know how it goes. We would be interested in hearing from your mom and finding out her area of expertise. Thanks.
 sarah-lou - Fri Nov 14, 2008 4:53 am

hi, i had my period on the 1st of october this lasted around 5 days. that period stopped and then i missed 2 of my contraception pills and came back on my period on the 12th of october for around 2-3 days. i went to the doctors yesterday and i fount out i was pregnant what period do i go by to find out how far gone i am?
 Debbie Miller, RN - Sun Nov 23, 2008 7:58 pm

User avatar Hello,
It is impossible to be sure but if your period seemed normal on the second time (Oct. 12) that will probably be the most accurate date. That would give you an estimated due date of July 19 or 20. Keep in mind the operative word here is "estimated" since we don't know exactly when conception occurred and this is not just in your case. These days almost everyone gets an ultrasound which can confirm gestation and help you determine if this date is the most accurate. Be patient about a date since they are not definitive anyway.

Best of luck to you.
 qtpiej2006 - Sun Jan 18, 2009 4:31 am

Ok my menstrual cycle was on the 21st of December and i had sex on the 2nd of January. I also ovulated on the 2nd of January....i took an ovulation test so i'm certain. I have a 20 day menstrual cycle and so far my period hasnt come on yet...could i be pregnant? My period according to the ovulation test is suppose to come on the 10th of January and it hasnt so far....please help.
 happykid71 - Tue Jan 20, 2009 10:12 am

hi i am 17. my last menstrual cycle was in august last year. what's wrong with me? im not under much stress, nor do i have any problems at home or with anyone. please help.
 Debbie Miller, RN - Fri Jan 23, 2009 6:56 pm

User avatar Hello (qtpiej2006),
You could definitely be pregnant so if I were you I would take a home pregnancy test which should be quite accurate now. Good luck.
 Debbie Miller, RN - Fri Jan 23, 2009 6:57 pm

User avatar To happykid71 -

It often takes several years for periods to become regular, if they do at all. You can be very normal and not ever have regular, predictable cycles. If you are sexually active, you should be concerned about the possibility of pregnancy. If not, this is definitely within the normal limits. You may not yet be ovulating every month. When the time comes that you wish to conceive, you can have this evaluated. Otherwise try not to stress over it since that alone can delay your period. But, your health does not depend on having a regular menstrual cycle.

Best wishes.
 lilly2000 - Tue Nov 10, 2009 8:10 pm

My period is late ??? Always normal good periods. Age 35 one 8 yr old child. Healthy too. 7/9/09 period~~7/30/09 period~8/25/09 period~~9/20/09 period 10/09/09 very early period..but very normal! Now its 11/10/09 and no period. Took a 3.00 test its neg. (today) My calculations show 4 days late. I have all period symptoms, sore breast, cramps, lower back aches..just right). 2 weeks ago bad cramps also (i think i was ovulating that day :) Is it possible since i had never had one come 2 weeks early like the one 10/9/09 that was a 19 day cycle, could this one for November be runing behind.
Or could i be pregnant ?
Thanks :)
 Debbie Miller, RN - Sat Nov 21, 2009 3:16 am

User avatar Hello,
Irregular periods are considered quite normal for most women. Nothing you have reported here is alarming and there is not enough information to guess at whether or not you are pregnant. But, why guess when home pregnancy tests are easy to obtain?

Many women begin to have period irregularity as they age, particularly in the peri-menopause which can occur years before menopause. You are not that old but the cycle alterations can happen at any time. It really isn't important for you to completely predict your cycles unless you are trying to conceive or using natural family planning.

Continue to chart your periods and when you see your doctor for your annual exam, having this history will be helpful. Of course there ia always the possibility of an underlying hormone or other problem so if this continues to be erratic your doctor might be able to help.

Best wishes.
 dopeypink16 - Thu Jun 17, 2010 1:36 pm

Hi, I'm 15 years old and i'll be 16 in July. I have ?had my period for almost 2 years now and all of the sudden it has become late by 7 days. I was supposed to start on the 11th and now it is the 17th. I don;t know what could be going on because i have not had sex so i couldn't possibly be pregnant. What could be wrong with me and what should I do about it?
 katherine1985 - Mon Jul 19, 2010 8:20 am


I have been taking the pill for years now and the last couple of days of my last packet i kept missing and now i am over a week late for my period!

could i be pregnant oh is this an affect from taking my pills like i did. i havent from what i can remeber have had sex where my partner as let his sperm go up me he as always pulled out before this. could i possibly be pregnant???

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