What Are The Chances Of Pregnancy After Taking Plan B?
Plan B alone will cut your pregnancy risk by 90 percent
Detailed Answer:
Hello, and I hope I can help you today.
In a healthy, normal ovulating woman, Plan B alone when taken within 72 hours of unprotected sex, reduces your risk of pregnancy to less than 10%.
In your case, with your history of fibroids, abnormal bleeding, and also having taken the hormone progesterone for 14 days prior to your active unprotected sex, the likelihood of having ovulated, let alone having conceived, is extraordinarily unlikely. In addition, you and your partner use the withdrawal method which is not as effective as hormonal contraception, but stillis successful in preventing pregnancy about 85% of the time.
So I really do not think that you need to be concerned about pregnancy at this time before your hysterectomy. As routine, the operating room will most likely check a blood pregnancy test within 2 to 3 days of the procedure as part of their standard preoperative evaluation. You will find out at that time if there are any problems, however the likelihood I really do believe is negligible.
I hope that I was able to adequately answer your question today, and that my advice was helpful. If I could be of any further assistance, please do not hesitate to contact me again.
Best wishes,
Dr. Brown
Oh, and I had read that Plan B wouldn't really be effective after ovulation. But you think there is a high chance I didn't ovulate, correct?
Yes much lower doses of progesterone are used for contraception
Detailed Answer:
Hello again,
There have been no studies on the effectiveness of Norethrindrone Acetate alone as a contraceptive, but Plan B only has 1.5 mg of Levonorgeastrel, which is another kind of progesterone, which is a much lower dose than the Aygestin you were taking. There are many types of synthetic progesterone used in contraceptives, and they all work at similar doses. So it is not recommended to take progesterone (not designed to be a birth control pill) to prevent pregnancy, but it makes biologic sense why it would work that way.
So it is logical that you likely did not ovulate while you were taking the progesterone, and the Plan B added additional protection. It is true that emergency contraception cannot stop an egg that has already ovulated from being fertilized, but the egg only is viable for about 48 hours. So if that 48 hours has already passed, you are no longer at risk for pregnancy and therefore would have no additional benefit to taking Plan B. Your thyroid disease would not necessarily affect your fertility one way or another if it is under good control.
So again, I really do not think you have to worry about having conceived in your situation.
I hope this information clarifies your question.
Best of luck with your surgery,
Dr. Brown