Can Women Get Pregnant During Menstruation?

health wellness

A woman can become pregnant from having sexual intercourse during menstruation. In fact, recent research conducted by the United States National Institutes of Health (NIH) suggests that women have the potential to become pregnant at virtually any time during their cycle. While the chance of pregnancy is greater on certain days of a woman's cycle, it is never completely absent.

While the rhythm method may be appropriate for couples trying to become pregnant, it often fails when used to avoid pregnancy. Dr. Allen J. Wilcox of the National Institute of Environmental Health Sciences even goes so far as to say that the rhythm method does not offer a significant advantage to couples trying to conceive. According to Dr. Wilcox, couples who simply have unprotected sex on a regular basis have as much of a chance of conceiving as those who wait for fertile windows.

A woman's cycle begins on the first day of menstruation, which is counted as day one. Traditionally, days 10 to 17 are said to be a woman's most fertile period. However, this is based on the idea of a very regular cycle, lasting 28 days, with ovulation occurring on day 14. In reality, few women are this regular; only 30% of women fit this model. In addition, even women with regular cycles do not always ovulate at the same time each cycle.

A woman's fertile period lasts for about a week each month. Sperm can survive in the cervix for up to a week, and the egg is viable for 24 to 48 hours after ovulation. The problem is that ovulation is highly unpredictable. Teenagers as well as women nearing menopause - two groups that are less likely to desire pregnancy - have the most irregular menstruation cycles. Thyroid disease also contributes to irregular cycles.

In the 2005 NIH study, Wilcox and his colleagues studied the menstruation cycles of 213 women, most between the ages of 25 and 35, when a woman's cycles are most likely to be regular. They found that a woman's fertile period can extend to the day when menstruation is predicted to begin. In addition, they found that a woman can become fertile as early as day 4 of her cycle, and that 17% are fertile by day 7. Therefore, menstruation is no guarantee that a woman will not become pregnant when engaging in sexual intercourse.

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I was just hospitalized with 'endometriosis'. I'm a 29 year old female who's never had children because of the endometriosis. I under went surgery to attempt to cure and get rid of the endometriosis, however, the surgery wasn't successful. The doctor did manage to clear out the right ovary, though the left one still doesn't work due to the endometriosis. I'm currently on an 'injection' to stop the production of estrogen in attempt's to starve out the endometriosis in hope's that it will die, and new cells can produce. Although, the doctor advised me to stop my birth control pills so the injection will be more effective. In the process, my boyfriend and I, began using protection on a regular basis, just in case I can still get pregnant. Even though, the doctor told me that he's never heard of anyone getting pregnant on the injection, yet he advised to still use a method of birth control while I'm off of the pills, and am strictly on the injection. The injection is taken once a month, for 4 month's. What is my percentage of getting pregnant while I'm going through chemically induced menopause? I'm curious so I can continue taking the proper precautions to keep me from getting pregnant during the process of me trying to get rid of the Endo.
- anon34753
i had unprotected sex with my boyfriend on the 5th day of my menstrual flow and i also took the emergency pill after 50 hours, and after 6 days, i had some bleeding. now i am 11 days late from my expected period. does this mean i am pregnant? i have had my period late by almost 15 days earlier too as i am always irregular.
- angell
the fact is..if you had unprotected sex any day of the month, there is a chance you can get pregnant. no one online can tell you if you are pregnant or not, the only way of knowing is taking a test. good luck.
- anon33170
I just want to ask..I am so worried now. I have taken pills for almost 7 months now, i don't want to get pregnant again. I just want to hear your advice for me please!

I had my menstruation first week of April but then i stopped taking my pills in the last week of that month and had my period that week also. So i am taken back my pills because i am having sexual intercourse with my husband. I want to stop taking pills this week. I can feel its like tender or sore i don't know. Then now i'm back taking the pills..Can i get pregnant? *Please help me.* I don't want to get pregnant again.

- rezzl
i had unprotected sex with my husband on day 3 of my period and this month i have not had my period. i got a checkup and test and test it's coming back negative, but my belly is looking big. what are the chances i can be pregnant?
- anon32701
I just had unprotected sex with my boyfriend, it's my fifth day on my period can I get pregnant?

- kk1234567
Please help! I usually have heavy periods. This month, my period came probably on time, maybe a little early, and it was lighter than usual. It was like this for about 2 days then I had unprotected sex with my fiance in the shower and now (the next day) *it is gone* 100%. My period usually lasts at least 7-8 days. It has *never* stopped early or gotten light early. I *rarely* get cramps or any discomfort during my period and this time around I have had such terrible stomach and abdominal pains, discomfort, gas and cramps. My breasts are enlarged and sore (which happens most times with my period, so not worried there too much). I'm not on Birth Control. Also when the bleeding stopped, i started having symptoms of UTI (out of nowhere). Is there *any chance I could be pregnant?* Or is it UTI or just stress?? *Please help!* I do *not* want a baby right now!
- lofa1210
I have been trying to get pregnant for the past one year after my last miscarriage but i couldn't, last month on the 8 day after my menstruation i slept with my ex-boyfriend just that day only, because i found out my husband is cheating on me, then two days after which was 10 days after my period, we got back together with my Husband and i slept with him on the 10 day and continuously, there after this month i found out i'm pregnant, i'm worried that the pregnancy is for my boyfriend or my Husband?
- anon32162
I had unprotected sex with my boyfriend twice and I didn't take my birth control for about 5 days or so, I'm not sure. Anyways, can I be pregnant?
- anon31975
i had unprotected sex with my hubby 3 days on my period, can i get pregnant?
- kmjpk
I had unprotected sex with my girlfriend, 3 days after my period, can I be pregnant?
- anon31789
Is it possible for a woman to get pregnant if she had intercourse 4 days before her menstruation?
- wondering1
Ok wait...I have read the article and all of the posts done by the girls here, I'm a guy, I had sex with my gf last night and it was her second day on her period, which she has been bleeding heavily compared to what she usually does during her regular periods, but the question here is, from 1-10 what are the chances that she will get pregnant from last night?
- darkshinobi
I had unprotected sex with my boyfriend, but the day after I got my period. Is there a chance I could still be pregnant? If so, what are my chances?
- whhsxc30
Hello,

I had unprotected sex. I was on my second day of menstruation. I don't usually bleed much during my period. I have my period every month and not exactly every 28 days. I did a pregnancy test two weeks after that sex and it was negative. I tested late at night after a long day of work. I am concerned because two weeks after the intercourse I started to feel strange. I started to feel bloated and always hungry. I find myself nauseating at times during the day and I have been sleeping a lot too because I am always tired, at least more tired than usual. Could I still be pregnant?

- pregnancy
I had unprotected sex with my boyfriend (stupid me I know), on the 10th day of my period. I have always been very regular with my periods except for the past year. I would like to know what is the possibility that I am pregnant or if there is a way of knowing before my next period?

Thanks

- nana1
I am 21 years old. I had sex with my boyfriend on the 2nd day of my period and on the morning of the 3rd day I was bleeding a little. I had sex on that day too and mid 3rd day I stopped bleeding. Now it's been 3 days after I last had sex, but I still haven't had my period. Please tell me if this means that I could be pregnant?
- Ange
I was on the last day of my period and I unprotected sex with my boyfriend. I have really irregular periods. Sometimes it takes even 4 months for my period and I was wondering what is the chance of me being pregnant?
- chaparra
I'm on birth control and it was the last day of my period (so tomorrow I would start a new pack of pills) and my boyfriend and I had unprotected sex. Is it likely that I will get pregnant?

- anon29863
If I have unprotected sex during my period and he finishes inside of me, could I get pregnant?
- shoms
I had sex on the 5th day of menstruation and my husband finished inside of me. Can I get pregnant?
- creep123
I was wondering what the chances of are of myself getting pregnant. One early morning, around 1:30 a.m., my spouse and I had sex and that same day around lunch I started my period. This is the first time we were not safe so I was curious. I'm currently on my period for the next couple more days, when should I do a test to see?

Thanks for your time.

- Curious09
Since this is just an information site, and each of you and your situations is different, I'd say the obvious answer to your questions is to ask your doctors.
- anon29379
I'm 15 years old and I had unprotected sex with my boyfriend a week before my period was due and I had my period after a week. Can I be pregnant?
- anon29015
i just wanted to ask if i can get pregnant? my period last month started around 21 feb 2009 and i had sex with my husband last mar 20 mar 2009 and i had my period 21 mar 2009. i really need your immediate response..thank you very much.
- sks2010
i had unprotected sex with my hubby 2 days before my period. can i be pregnant?
- anon28746
i had intercourse a week before i got my period, i took the plan B, but a week after that we had intercourse again, but he just put it in once then stopped and the same day i got my period, but now i'm only bleeding dots... could i be pregnant?
- br1188
My name is Rose. I am one month pregnant, but am still seeing my menstruation. I did my urine test and it was confirmed positive, then i asked the person in charge the course of the menstruation. She said maybe i have an infection and that is true. So what can i take to cure the infection, because i was having stomach pains and i cannot work? Thanks

Rose Jacob

- anon27763
Hi,

I had sex with my boyf when I had my period (on two separate days), and after the second time (so two days after the first time), my period stopped really abruptly.

Could I be pregnant, or is it just a coincidence?

Please Help!

- anon27530
hi! jz want to ask my last menstruation started february 24, lasted feb 28, then had intercourse march 1, is there any possibility that i'm pregnant? this is "K"
- anon27514
i just finished my menstruation and started taking my pills, but i had stopped my pills for 2 days and on the 3rd day i had unprotected intercourse with my partner, i didn't continue my pills anymore, but after 4 days, i had my menstruation again, is it possible for me to get pregnant? i'm just wondering cuz i am taking diet pills not suitable for pregnant women..looking forward for your answer..thanks a lot!
- anon27508
hi..just want to ask, my last menstruation started Jan 28, lasted Feb 2, then had intercourse Feb 5. regularly having menstruation every 28 of the month.. now Feb 28, i'm expecting to have menstruation. is there any possibility that i'm pregnant at this time??
- najnell
hi, i was wondering if a woman can get pregnant five days before and after her cycle.
- babydust
I had unprotected sex with my partner. I started my menstrual cycle five days later, is it possible that i could get pregnant?
- anon25961
is there a possibility that two eggs are present during ovulation and one gets fertilized and the other doesn't resulting in a period, and your pregnant at the same time?
- anon21410
Hello, I have been taking my pills and having my periods. Is there any possibility that I am pregnant?
- tatis211
hi there..i just want to ask if it is possible to get pregnant in the last day of my menstruation without any protection?
- anon18314
it is possible for a woman who is pregnant to have menstruation?
- pleasant
hi there,i just want to ask if i get pregnant. my period last month starts around july 2,2008 and i have sex with my bf last july 29,2008 and i have my period august 1,2008 i want to know when will i can have a pregnancy test for me to know if i am pregnant. i really need your immediate response..thank you very much.
- jialo
Hello, i'm using contraceptive pills i had sexual intercourse during the free pill week. Did not get my menstrual period until 7 days after the expected day. It was an abnormal menstruation and received really painful cramps. Is there a possibility of getting pregnant?
- pmedellin
Gracey, Lxrmusic, Plandi, Rokdemsox - As the article states, you can get pregnant before your period starts, while you're on your period, on the last day of your period, and after your period. Whether you have a regular or irregular cycle does not matter -- you can still get pregnant. While it is less likely that you'll get pregnant after you've started your period (because ovulation typically occurs in the middle of your cycle), it is still possible to get pregnant at any time. If you are not prepared for pregnancy, always use birth control.

Gmbn - The percent chance that you will get pregnant depending on when you had sex in relation to your period can only be determined if you track your own ovulation.

Madeinchina - While it is uncommon, you can be pregnant and still have your period. If you think you might be pregnant, consult your health care professional. If you are not prepared for pregnancy, use birth control.

Toogi & Stewy84 - If you are properly taking your birth control pills, as instructed by your health care professional, you will not be more likely to get pregnant if you have sex during the week that you are taking the placebo pills.

Dop3y137 - Changes in your menstruation can be normal or it can be a sign of something amiss. The only way to know for sure is to contact your health care professional.

If you are trying to determine the best times to get pregnant, you'll have to chart your ovulation. If you don't know how to chart your ovulation, contact your health care professional, or Anon3641 suggests you can read about the Billings ovulation method.

- habura
I have been taking the birth control pill religiously for the past 10 years. I recently engaged in unprotected intercourse on the third and fourth days of my menstrual cycle. Is there a chance that I can become pregnant during the week of inactive pills? I started a new pack the Sunday after my period began. Any comments would be helpful
- stewy84
hi, i usually have a very heavy period lasting up to 7 days recently my period lasted 2 days and was extremely light.. what can this mean??
- dop3y137
What are the chances of pregnancy if my partner and I had unprotected vaginal intercourse Day 1 and Day 2 AFTER her period was over? Very low probability? Thank you.

- gmbn
Hi! I had unprotected intercourse on May 10, then my menstruation came on May 23, are there possibilities of getting pregnant?
- madeinchina
I had unprotected sex (purposely) with my partner the day after I had stopped bleeding. And also the three days following.

This was about two and a half weeks ago. I know nothing about pregnancy, as I am only 17 and was just wondering, is there any way that I could be pregnant. I still have about 10 days until I start my period. And I am looking up different things about early pregnancy. I didn't even know that someone could get pregnant before the 7-10 days after their period. I was just wanting anyone's advice on how I could approach this situation. and for those of you who have gone through pregnancy, are there any other signs or symptoms that I should expect this early on if I am pregnant?

Thank you!! :)

- rokdemsox
hello., im using contraceptive pills. and it has 7 free-pills day. during this 7 days my cycle had came and we had intercourse. Is it possible to get pregnant?
- toogii
would it be possible for a woman to get pregnant when she has intercourse a day after her menstruation?

- plandi
Hello,

I had unprotected sex during my second day of menstruation. The blood flow is very light. What are the chances of becoming pregnant?

Thanks

- lxrmusic
would it be possible for a woman to get pregnant when she have intercourse a day after her menstruation?
- gracey
You can know exactly when you ovulate. Read about the Billings ovulation method. Everyone is different, that is why you should know yourself.
- anon3641

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