UMMM...Birth control question.

So a friend of mine got into a debate with some class mates and I'm confused by their logic as is my friend. So, riddle me this; birth control STOPS ovulation, correct? The argument is that the egg builds a shield around it thus preventing fertilization. Was my high school health teachers and doctors wrong all of this time?? The egg forming some unknown force field due to birth control doesn't seem right.

I was always told that birth control (the pill, mostly) stops ovulation all together.
TIA

Quoting Suckafish:" So a friend of mine got into a debate with some class mates and I'm confused by their logic as is my ... [snip!] ... birth control doesn't seem right. I was always told that birth control (the pill, mostly) stops ovulation all together. TIA"

i've never heard of it building a 'shield' i've always heard the same as you...that it stops ovulation.
the egg does have a 'sac' thing around it before it bursts out of the ovary...maybe they're getting that confused?
can't remember what it was called...ugh..and it was the last thing we studied in a &p 2..i should look that up.

Bear with me, I'm hella tired.
Certain birth controls do stop you from ovulating I believe, some make the lining of your uterus too thin for implantation, etc. There's a lot of methods, but I've never heard of a magical anti-sperm force field.

Most birth control works in three ways, one of which is preventing ovulation, yes. It also thickens cervical secretions, making it more difficult for sperm to get through, and thins the uterine lining to make implantation more difficult in the event that a woman does ovulate.

Non-hormonal birth controls (like certain IUDs) and the mini-pill do not prevent ovulation, however. The mini-pill does sometimes, but not always.

Birth control tricks your body into thinking you are pregnant. When you are pregnant you don't ovulate. Eggs don't create a force field I think some of those students are watching to many sci-fi movies

most birth controls work 2 ways. They change the acidity of the cervical mucus to kill sperm, and stop ovulation. that way, if you do ovulate, sperm should be killed off.

I was on birth control for years, getting 2 periods a month. My doctor when she found out told me the first step was all that kept me from getting pregnant because I shoudln't be having extra periods. IT showed I was still ovulating... which the pill should prevent. she upped my dose so I wouldn't ovulate in addition to the pill changing my mucus.

They could be thinking about Plan B. When I took it at Planned Parenthood, that's how the nurse explained to me how it worked -- if you did happen to ovulate, it would harden your egg or something so the sperm can't get through. But as far as I know, most methods trick your body into thinking it's pregnant.

Okay, thank you ladies!
Her whole class (even her professor) were agreeing that birth control does not stop ovulation and the eggs in fact, create a shield (similar to the amniotic sac) when on birth control. I DON"T UNDERSTAND THEIR LOGIC.