They just had a Watchtower magazine on this…
**1. **The couple can choose to have a JP perform the wedding with or w/o a Kingdom Hall (KH from now on) ceremony. They can do it in front of the JP or in the KH in front of an elder.
If they do it w/a JP, the couple has to decide whether or not they want a “ceremony” or speech done at the KH, but the ceremony has to be held w/in a few days of the civil marriage, preferably w/in 1-2 days.
Just remember one thing, if one is not a JW, then they cannot have a KH ceremony. Also, if they have had premarital sex, they cannot have a KH ceremony. If one is disfellowshipped, they cannot have a KH ceremony.
Since at least one would be a JW, then they cannot marry through any church. The JW is only allowed to have a civil marriage. But they always discourage you from marrying anyone outside of the faith.
http://www.watchtower.org/library/g/2002/2/8/article_02.htm
**2. **They are not reprimanded if they have too many children, however, they do encourage you have the least that you can. They enocurage contraception so the couple won’t have “too many” children. They say just have as many as you can afford to support. They rather have you spend your time going door to door to “spread the good news”.
They also get procedures done after they’ve had as the children they wanted to have.
Oh, and the contaception form has to be like a hormone based one, not one that induces abortion.