although i applaud your motives, childbirth is NOT the way to bond with your children. since this is your first delivery (i'm assuming) you have no idea what will happen. contrary to what we wish to believe, childbirth (other than a scheduled c-section, to some degree) is not able to be planned, staged nor predicted. also, there is no way that you can predict what your children will or will not see--the whole "they'll stay at the head of the bed",is not an absolute. this might end up being more confusing and traumatizing to them than any bonding you anticipate. especially if you begin vocalizing in pain.
although i am not an adoptee, i must defer (and agree) with the response by linny--witnessing you give birth might trigger feelings of insecurity over their adoption.
delivery rooms can be scary for children. there is lots of equipment, unfamiliar sounds, people "barking orders", and *maybe* screaming. they'll be lots of medical staff running around, procedures; and blood and misc. bodily fluids (yes, it is very possible that you will vomit, defecate, or urinate during delivery).
unlike the "birth shows" there is no editing and "modesty shots." you will most likely be fully exposed from the chest down, and the staff will not make extra accommodations to protect your children from seeing "unsightly things" other than requesting that they leave.
also, labor can be very LONG and painful for a first mom. you never mentioned if you tend to labor naturally or with anesthesia? there's a difference. many women become sedate after anesthesia, or vomit, loss control of their bladder, et al. in contrast, women who labor naturally usually vocalize more, and the sounds can really scare your children.
hence, your children might get bored, tired and cranky and scared. there is nothing worse than to tend to cranky, scared kids while one is in labor.
as such, i strongly believe that there are many other ways to help your children bond. perhaps they can decorate the room, or pick out the going home outfit. or help change diapers (after the cord has fallen off). but, having them witness your birth is probably not the best way.
to be fair, my son did attend my daughter's birth. he was with me during most of my labor. but left the room when i went into transition; and did not return until after she was delivered. my son was also 14 YEARS OLD, was a bit more mature, and my labor was relatively uneventful. yet he vowed NEVER AGAIN until his partner is having a baby.
i sincerely wish all the kiddos and new bebe lots of love and smooches. and i hope you have a wonderful pregnancy and delivery.
delivered 3 children, had my 14 yo attend my labor, and do NOT believe childbirth is appropriate for a mother's young children to witness.