You're going to hear alot of different answers to this question... Some will say 1 week, some will say one month.. And others will say 3 months.. I'm on marvelon and started not using protection after one week (if I started my pills on day one of my period)... Only because this is what the marvelon website said the time was for it to be effective, however i've read that just to be on the safe side, use protection for the first month... And during this first month you have to remember to take your pills 100% right. Any mistake could cause an unwanted surprise!

Thanks - I didn't even think to try to look it up online. The yasmin website says its effective after one week.

Birth control becomes effective after whatever the specific brand says. However, no b/c becomes fully effective until after three consecutive months of taking the pill faithfully each day at the same time. I cannot believe how many doctors do not explain this to their patients. Some people do not use back up at all and do not conceive. When others wait the week or two weeks or month that everyone mistakenly thinks it the correct time and then they do become pregnant. Bottom line, if you do not want a little one, use condoms. B/c is only 98% effective anyway. People get pregnant on the pill everyday.

If you are saying that it takes 3 months for the birth control to become effective - why would the manufacturer's website say it becomes effective after one week if that isn't true?

Yea, I don't know why specific bc websites say that their pill is effective after a certain amount of time if it actually isn't.. I don't think that they want us to be getting pregnant!! But like I said, im on marvelon and the website said that if I started my pills on the sunday after my period, that I would have to use protection for a full month before it would be effective. However if I started my pills on the first day of my period that after one full week they would be effective.. I started the first day of af and took it for granted that the next week I could go without a condom and anything else.. I have had no problems since then (however I did have some spotting throughout the first month, but I think that was just my body getting used to it, it hasn't happened since).

I am on day 9 of my period. I'm on day 7 of my birth control. My periods normally last 4 or 5 days. Is it ever going to stop? Is this normal? This totally sucks. This is one of the reasons I didn't want to go on it in the first place.

Check back with your doctor.. The pill he/she gave you might not be strong enough or there might be something else wrong.

This is what I don't understand. These companies advertise that their pill (or patch or whatever) becomes effective after one week. You're either fertile in a month, or your not! You ovulate once a month so if it's not safe the first week, than its not safe the first month. I think different companies claim their pill is effective after one week for two reasons.... Marketing - have to stay competitive.. Who wants a pill thats effective after three months if theres another pill available thats effective in the first month, and 2, to cover their ass.. If someone did get pregnant during their first month, they have that first week where the pill "might not have been effective" to blame.

Birth control companies cannot be held responsible anyway, because there is no way to prove if the woman took the pill every day at the same time everyday. So, if their was a lawsuit, it would just be he said she said and charges would have to be dropped. I am sticking to what my doctor says, I don't care what the b/c companies say.

I didn't say anything about lawsuit. It's all marketing.

I am sorry. When you said that they would have that it may not have been effective in the first week, that is what I thought you meant.
But anyway, I was not really directing my last post at you. I agree with you on the marketing thing 100% I am just trying to make people understand that the b/c company can say it is effective after the first pill, or first week, because they cannot be held liable if it is not. That is why I choose to listen to my doctor instead of them. That is all.

I would have a hard time believing my doctor over the manufacturing company. My docter is not involved with the development or testing of a particular drug so why would he/she know more about it than the company that manufactures it? Granted those companies want to push their drug and make their money but they would be extremely liable if a bunch of women had unprotected sex after a week on birth control and got pregnant after following the drug's directions. If it only happened to a few women it would be a fluke. But if it started happening to hundreds or thousands of women, the company would be liable for making a faulty drug or making false claims about the drug. There are lawyers everywhere who have gotten rich off of these kinds of lawsuits.

This is true, there are. But, the fact of the matter is that it cannot be proved.
Like I said, you all can believe whatever you want and more power to you. But, I love my doctor and she has never steered my wrong, so I personally listen to her. That is my perogative and that is what I choose to do. That is just me.

I just got BC again, I am about to start taking Ortho Tri Cylcen Lo... (have any of you had experice with it?) And I am going to start my period in a few days.. I am wondering if i should wait to take it with 24 hour of my period (manufactuer says it would be effective immediatly if taken with 24 hours of 1st day of your period) or just take it today and wait the week like it says for it to be effective. Thoughts?

i've been on yasmin for nearly a month, and my period has been going for the whole duration but extreemly light. my dr. didn't even tell me when it's effective but the majority of people say one full month.

I was on the depo shot for a total of 6 months...and for everyday of those 6 months i bled. SO I'M TELLING ALL OF YOU, DO NOT USE THE DEPO SHOT!! It's been about 3 years since the maddness happened and the only thing that saved me was God and the Pill. My doc kept telling me to give the depo one more month (hell she wasn't the one bleeding) but I told her, Hell no. She then gave me the pill and told me in a 1-3 days the bleeding should end. THANK GOD IT DID!!

I said that to say this, Long Period, if you've been bleeding too long then tell your doc you need something else. The hormones could be too high or too low for you. I was placed on the pill Levlen and it worked. You may ask about that.

As for everyone else, the effective date of pills vary from site to site. Blame it on the pills, marketing, or on the alcohol, but the bottom line is if you want to ensure that you're not gonna end up preg...you may want to consider a back up method.

Best Wishes 2 you All!!