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    How effective is Plan B emergency contraceptive in preventing pregnancy?

Posted on Tue, 24 May 2016 in Pregnancy
Question: I had unprotected sex and my boyfriend did not ejaculate in me so to be cautious I took the Plan B 17 hrs later because I was worried about my uterine fibroids. I am 46 yrs old and weigh 165lbs. I am 5/6. My last period was Feb 20th and I am due between march 16-18. I have been experiencing lower abdominal cramps, bloating and gassy. I burp a lot more than normal with flatulence. The cramps feel like my period wants to come especially on the 16. The cramps are not severe but enough to notice. I took a pregnancy test on March 16 but it was negative. I had sex on March 7th and took the pill later that evening. Do you think I might be pregnant and will my period come much later? Also is that the side effects I am experiencing from the Plan B pill?
Thanks for your help.
Answered by Dr. Zenab Tambawala 27 minutes later
Brief Answer:
Very unlikely that you are pregnant.

Detailed Answer:
Hi there,
Welcome to HCM,

Do not worry.

It very very unlikely that you are pregnant. At 46 years the chances of pregnancy are very low, moreover you have taken plan B which is 99% effective if taken within 24 hours of unprotected intercourse.

After taking plan B it is common for the next period to be delayed by a week or so. Do not worry.

Just repeat the home pregnancy test 21 days after you took the pills, that is on March 28 if you have not got your period by then.

Plan B does not have any other side effects apart from the occasional delay in periods. The symptoms you are experiencing are probably due to the fact you may be getting your period soon and these are pre-period cramps and uneasiness.

Hope this helps.
Above answer was peer-reviewed by : Dr. Sonia Raina
Follow up: Dr. Zenab Tambawala 32 minutes later
I was curious about the bloating and gassiness. It started 4 days after I took the pill. Is that a side effect of the Plan B pill?
Answered by Dr. Zenab Tambawala 57 minutes later
Brief Answer:

Detailed Answer:
No, it's very unlikely that its due to the pill. If it was due to the pill you would have felt symptoms the same day rather than after 4 days.

These symptoms could be because you will be getting your period soon and this could be premenstrual symptoms.

Hope this helps.
Above answer was peer-reviewed by : Dr. Deepak
Follow up: Dr. Zenab Tambawala 6 hours later
Ok. Thanks but I did some research and bloating and cramping are some minor side effects of the morning after pill. Apparently many women have experienced the same issue. I guess it will go away in time? Also how long will it take for my menses to get back to its normal cycle?
Answered by Dr. Zenab Tambawala 2 minutes later
Brief Answer:
the next cycle will be normal.

Detailed Answer:
Your next period will be on time. Only the first period after taking the morning after pill is affected.
The bloating and other symptoms of cramping will go away as soon as you get your period.
Hope this helps.
Above answer was peer-reviewed by : Dr. Yogesh D
Answered by
Dr. Zenab Tambawala


Practicing since :2005

Answered : 837 Questions


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