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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144
I am 35 years old and i have a menstrual cycle of 26, 27, 28 and once in a while, 29 days, but this mouth i had a 30-day cycle. Throughout this year i only had sex in February, but my fear is that i now had unprotected sex on the third day of my menstruation, after which i still bleed. can i get pregnan ? and if yes please do advise me on a pill to take because i have no plan for any baby yet.
- floxybeauti
143
okay so i had unprotected sex and i took PLAN B 16 hours later, and six days later i got my period. i thought that since i still got my period right on time there is no chance of being pregnant, but i'm not sure, s, what are the possibilities that i could be pregnant?
- anon52190
141
Hi I want to know if it is possible to get pregnant? My menstruation is so irregular I don't have my period for about six months and my friend give me a trust pill and I take it for only 9 pcs of pills and I stop to take after two days I have my period and after seven days of my menstruation I have unprotected sex with may husband. is it possible for me to get pregnant? please advise. Thanks!
- anon51446
140
i had sex with my boyfriend, using a condom than we had unprotected sex twice that day but neither one of us knew i had just started my period till we saw blood. he never came in me but i was wondering, what's the possibility of me being pregnant?
- anon51331
139
me and my wife had unprotected sex but it was her 20th day in her cycle. will she become pergnant? please tell me.
- anon50877
138
i had unprotected sex with my boyfriend on the third day of my menstration. after our sexual intercourse i was bleeding. is there any way possible that i can get pregnant? thank you.
- anon50691
137
what is the answer to the question? can I get pregnant if I had sex with my husband during the second day of my period?
- anon50459
136
my last period was late September. (bleeding) and i had unprotected sex in mid october. i have a 31 day cycle usually. any chance of pregnancy?
- anon49984
135
which is 100 percent? safe sex before menstruation or sex after menstruation?
- anon49366
134
I had unprotected sex about 2/3 weeks ago. i was about a week late for my period then i bled a little bit two days ago whilst having sex with my boyfriend, so i thought i had come on. But the next day there wasn't any bleeding and i haven't bled today. What does this mean? Am i likely to be pregnant?
- anon49286
131
i had sex with my boyfriend and i had my period right after. on the same day it was heavy and later on it became light. the next day is also light. when i pee the blood doesn't normally come out like it used to. only when i wipe. what's wrong with me? is this normal?
- anon48951
130
I'm having an ultrasound, Is it possible to know the weeks of the fetus, to determine the father.
- anon48913
129
Anon48862: Odds are, the pregnancy is by the second guy, but the only way to know for certain is to have a DNA test done on the baby after it is born. Both potential fathers will contribute a sample and the test should rule one out.
- anon48865
128
if the girl has sex on the first day of menstruation is it possible to get pregnant? the menstruation ends on the third day and after 11 days she has sex with the other man. it's possible to be pregnant. now the girl is pregnant. how she will know which one of the two men is the father of her baby?
- anon48862
127
hai my last period was on in late september. my husband and i had sex in early october. now is 10 days after unsafe sex. can i get pregnant? please advise. i have to know.
- anon48613
126
I had unprotected sex with my boyfriend on the first day of my period. What are the chances that I am pregnant?
- anon48279
125
i had sex the first day of my period. after that i was just spotting. could i be pregnant?
- anon47992
124
i had sex with my girlfriend on her first day after menstruation. my girlfriend is pregnant, It isn't possible for her to be pregnant or is she playing games with me?
- anon47433
122
I had unprotected sex during my second day of menstruation. The blood flow is very light. What are the chances of me becoming pregnant?
- anon45461
121
i had unprotected sex with my hubby within two days of my period. can i be pregnant?
- anon45460
120
hi i don't have my period yet but i have done menstruation. can i get pregnant?
- anon45411
119
I had unprotected sex 89 hours before I took a pregnancy test that came up positive and I am definitely pregnant. Is that possible that enough hcg would show up in my urine to cause a positive in a home test so early?
- anon44318
118
is it true that having sex increases the size of ones breasts and that it is even possible for someone who is of age, let's say 20 years and above and doesn't have her period for over a month not from any reason (sex) whatsoever but just a break to have sex whenever she likes? Even after a check up it seems there is nothing wrong.
- bmshatlin
117
is it really true that having sex can increase the size of one's breasts and you can get pregnant no matter what and even after the pills?
- anon43773
116
Could I get pregnant on my fourth day of my period? Should I take Plan B to be safe?
- anon43666
115
i had sex on the second day of my period. is there any possibility of being pregnant? should i take any contraceptive pill by 72 hours?
- anon43555
114
Me and my boyfriend had sex and the next day I started my period We also had unprotected sex a couple of days later. I usually bleed for five days but I only bled for three days and then I stopped, but started spotting the next day for a few hours. Could i be pregnant? i have been sick since about a week after my period and haven't been able to keep anything down.
- anon43129
113
I just had unprotected sex with my boyfriend. it's my fourth day on my period -- can I get pregnant? and then after that day i took injectable contraceptive. what will happen?
- pom08
112
Hello! I had sex with my husband a day before my period, any chances to be pregnant?
- anon42488
111
my fiance and i had unprotected sex the night before my period and the day of my period. Could i get pregnant? We are trying to conceive!
- anon42135
110
hello. if we had sex during the second day of the period. what is the possibility of pregnancy? thank you.
- ab123456
109
i had sex with my girlfriend on the fourth day of her periods. is there a risk of her getting pregnant?
- anon41585
108
Hello,

I had unprotected sex with my boyfriend on the forth day of my period he came inside twice. can i get pregnant? when will i know or when could i check myself if this happened a week ago?

- anon41383
106
Hello, I just had a period this past week. And while bleeding i had unprotected sex with my boyfriend. Could i possibly be pregnant? And if so when will i know for sure that i am pregnant?
- shantel12
105
Hi: I had unprotected sex with my boyfriend 4 days after my period. it usually is a 27-day cycle. i got my period on the 11th and finished on the 16th. At the time i had a little sharp pain on my left lower side of my ovary. i kind of think i was ovulating at the time. after sex the discomfort went away, i being feeling a little different. i feel bloated and my breasts feel funny but they dont hurt. i feel over tired, gassy, my stomach feels heavy and i had cramps here and there then they go away, i am not due for my period for another week or so. i took a urine pregnancy test in a clinic but it was only 6 days after the fact and the result was negative. i was told it might be too soon for hcg to show. can i get some help on this topic or advice?
- supersexy
103
My last period started on 28th of June. I had intercouse on 20th of July by using the condom. Unfortunately it got torn off. I had lognyon contraceptive medicine as per the doctor's advice. Normally my period cycle will come in 28 - 30 days. I yet to get my period this month.

I am little bit worried whether i am pregnant? Please advise.

- anon38878
102
i had sex with my girlfriend during her menstrual cycle. after sex she took a contraceptive pill. could she become pregnant as her menstrual cycle is still going on.
- anon38609
101
would it be possible for a woman to get pregnant when she has intercourse 1 or 2 days before her menstruation?
- anon37993
100
hi, have never been late for my periods, they always came every 28 days, and they always lasted 4-5 days, only heavy on the first 2 days. Three months ago I had unprotected sex, and I took the "morning after pill", the following month I got my period on time for 3-4 days, the next month, my period was late 10 days and it only lasted 2 days, now this month (the third month) my period was late 2 days and it only lasted 2 days also (I have had no sex since 3 months ago, and the pregnancy tests are negative).

Is this secondary effects from the "pill" or can I be pregnant? or is something else wrong? why is my period lasting only 2 days??

- anon37247
99
Well I had my last period on May 22, 2009 and it lasted for 9 days. Well I had unprotected sex the day after my period Sunday 31, 2009 and then 6 days later Saturday June 6, 2009 when I was certain I was ovulating. I spotted that following week Friday June 12, 2009. Well I took several different kinds of home pregnancy tests, but the tests came back negative.I hadn't had my period in June at all. I showed several signs of pregnancy. But then I started bleeding in July on the 7, 2009 but this was shorter and lighter(my peroid hs been regular for 2 years now). I had sex again uprotected on my sixth day of my period and my seventh day and I noticed my period had stopped on my 5th day that has never happned and two more pregnancy tests and still all are negative. I will wait for my next period but I'm so confused I still feel as though I am pregnant.
- anon37015
98
my period is irregular...i have taken all the nesessery tests according to my doctor's suggetion.. i am 19 years old..my period scale is like-one month regular,one month irregular.my doctor told me that my period will become regular after marrige..but i am afraid if i dont become pregnant,if my period dont get normal after marrige then what will happen?? Please answer me....
- anon36410
97
Hi i Just have some few questions.... me and my boyfriend had unprotected sex in February 2009. after that we stop making love. i got my period march and april. but in june and july i still don't have my period. is it possible that i am pregnant?? but i got a 2 months period... and now i am delayed of menstruation for 1 and half months...
- ganda
95
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
94
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
93
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
92
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
91
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
90
I just had unprotected sex with my boyfriend, it's my fifth day on my period can I get pregnant?

- kk1234567
89
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
87
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
86
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
85
i had unprotected sex with my hubby 3 days on my period, can i get pregnant?
- kmjpk
84
I had unprotected sex with my girlfriend, 3 days after my period, can I be pregnant?
- anon31789
83
Is it possible for a woman to get pregnant if she had intercourse 4 days before her menstruation?
- wondering1
81
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
80
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
79
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
78
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
77
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
76
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
75
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
74
If I have unprotected sex during my period and he finishes inside of me, could I get pregnant?
- shoms
72
I had sex on the 5th day of menstruation and my husband finished inside of me. Can I get pregnant?
- creep123
71
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
70
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
68
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
67
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
66
i had unprotected sex with my hubby 2 days before my period. can i be pregnant?
- anon28746
65
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
63
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
62
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
61
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
60
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
59
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
58
hi, i was wondering if a woman can get pregnant five days before and after her cycle.
- babydust
57
I had unprotected sex with my partner. I started my menstrual cycle five days later, is it possible that i could get pregnant?
- anon25961
54
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
51
Hello, I have been taking my pills and having my periods. Is there any possibility that I am pregnant?
- tatis211
48
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
46
it is possible for a woman who is pregnant to have menstruation?
- pleasant
38
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
35
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
34
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
32
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
31
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
24
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
23
Hi! I had unprotected intercourse on May 10, then my menstruation came on May 23, are there possibilities of getting pregnant?
- madeinchina
18
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
17
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
13
would it be possible for a woman to get pregnant when she has intercourse a day after her menstruation?

- plandi
7
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
4
would it be possible for a woman to get pregnant when she have intercourse a day after her menstruation?
- gracey
3
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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Written by Niki Foster
Last Modified: 20 November 2009

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