I have been doing a little research...
I am not FOR or AGAINST this Lifestyle - I am trying to present just factual info here
Everyone can form their OWN opinions
For everyone who has questions Google QuiverFull or Quiver Full or QuiverFull Nation There is a growing movement - soldiers for Christ kinda thing. Mary Pride and Rick and Jan Hess (and others) have written "manuals" containing Biblical based arguments for the lifestyle and the belief that only God can open and close the womb - the "high holy temple" of marriage.
The Duggar's embrace de-facto Quiverfull "leader" Bill Gothard who has no children and has never been married. His organization is where the Duggars get their home-schooling materials and there are even college degrees available. They call it "Training" their children.Home Schooling is encouraged with Quiverfull families - as is social isolation from those who do not embrace their beliefs. Family "compounds" are popular with male children building homes near their parents.The Duggars have 20 acres for that reason.
Women are encouraged to be "modest" in their dress, make-up is allowed so long as it's tasteful and women are to grow their hair long as the Bible teaches. The Mother/Wife rules the home (and "trains the children") and the Husband /Father brings in money and rules the family - often they are self employed (as the Jim Bob Duggar is). Many are "Contractors", "Missionaries" and involved in Real Estate or Politics. Women are allowed to be midwives - a vocation at least two of the Duggar daughters are professing to strive for. They do attend their Mother in births as those attending the birth are supposed to only say POSITIVE things about the womb, birth etc. Quiverfulls believe that the attitude of the parents and those of the family, friends, Drs and attendants before birth and at the birth MUST embrace only the positive.
Quiverfull families are Patriarchal (husband ruled) and conservative. Men, and ONLY men, are considered the proper "rulers" of the earth/world. They are LITERAL interpreters of the Bible and believe in both the old and new testaments as fact - obviously they embrace creationism. They believe in courtship - a sort of arranged marriage between the parents of the two young people - and there is no physical intimacy before marriage - the 1st kiss is to be on their Wedding day. No dating, no kissing, no intimacy - period. Both are to abstain from EVERY form of intimacy with the opposite sex and any time alone together comes ONLY after marriage. Ultra-Virgins - pure in every way. And BTW, they believe your children can be affected by what your ANCESTORS did and believed. They do NOT believe in divorce and after a divorce you cannot re-marry.There is NEVER any birth control and sex is indeed encouraged as a covenant of marriage - always "fruitful" sex, of course.
You have to dig a bit to find this but they do not adopt because they believe that heredity can affect the child - the sins of the father (and mother) literally are laid upon the child. If the mother and father did not want the child then the child will "be cursed" with that - may not be "trainable", may be barren, may have other issues. It comes up a lot - if they want so many kids why not adopt? You'll note Quiverfull families are always born - never adopted. They only have the children God gives them - be it 1 or 20.
Very interesting reading, to say the least.
Some Links To Get You Started
http://www.quiverfull.com/index.php
http://www.therevealer.org/archives/timeless_002709.php
http://www.hslda.org/docs/nche/000000/00000069.asp