Condoms are designed and tested to be worh through an entire act of intercourse, so if that is what you are asking, yes. Withdrawal is no more effective as an attempt at birth control with a condom than it is without one.
using a latex-safe lubricant does a couple of things. One, it helps keep your condom and vaginal canal from getting dry, which causes extra friction and can contribute to tearing a condom. As well, intercourse with lubricant when wearing a condom just plain feels better.
If you ever have a condom rip or tear on you (though honestly using good quality condoms with lubricant keeps that from happening nearly all the time), during intercourse, before ejcaulation, simply have your partner withdraw carefully, remove it slowly and use a new one. While there is going to be a higher pregnancy risk than there would have been without a condom, it's actually pretty slight more times than not. If you ever, after your partner has ejcaulated, discover your condom had ripped without your noticing, the smartest thing to do is treat it like an incident of unprotected sex. In other words, you will have had a high pregnancy risk, and if you do NOT wish to become pregnant, seek out emergency contraception.
In general, what I say about JUST using condoms as birth control is this: you've got to understand that while the protection it provides is very good when used properly, there is still room for a risk. To make that next to nothing, if you simply CANNOT or do not wish to become pregnant, couple your condom use with a reliable backup method of birth control such as oral contraceptives.
In terms of your last question, neither of those things has any impact on birth control or pregnancy.
Editor and Founder, Scarleteen
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