I don;t know much about it, but I'd imagine that during pregnancy, your body's protein goes a great deal into the developmentof your baby, and if you cut your hair, it will react differently without as much support (regarding protein and vitamines) from your body.

My understanding is that some people might say to hold off on cutting your hair because the shape of your face might change during pregnancy as you carry some extra weight. People might also say that because of some chemicals used in treating hair (dyes and the like) that might be risky for an unborn kid. I seem to remember my sisters finding that their hair was thicker during pregnancy because of all the hormone wackiness. I'm not sure what - if anything - that means for your question.

It doesn't matter when you cut your hair. The hair is dead and has nothing to do with the body. However hair normaly cycles from growing actively for years and then will rest for a few months. At the time of rest the shaft will be weak and will break off and this is why we loose a certain amount of hair each day. During pregnancy many more of your hairs will go into the resting phase so you may not need to be cut. But after you deliver and those hairs start growing again they will have a weak spot and break off in much larger numbers than normal. That is why pregnant women seem to loose so much hair after having a baby. It will return to normal no matter what you do.

I was a hair stylist for 12 years and I can tell you from experience most women cut their hair when they are pregnant. It does not, in any way, change your hair other than to make it shorter. Pregnancy, on the other hand greatly affects your hair. It usually makes it shinier, healthier, and grow faster. This is not always the case, however.

"Pregnancy Hair: Don't go drastic. At the moment when your body is in a constant state of flux, you may be tempted to exercise control over some part of your life. For example: getting a major haircut. Bumble and Bumble stylist Nikki An notes that many pregnant women come to Bumble and Bumble to get a new, easy look, and often want to cut their hair off. An recommends that they keep their locks longer, softer, and never make a drastic change — as they'll most likely regret it later. Keep in mind that having shorter hair doesn't always mean that it will be easy or less time-consuming to style. It's a good idea to stay within a range of length and shape that you're already comfortable with. Pregnancy Hair: Consider your new face shape. Many women find that their faces get fuller during pregnancy and should consider that when getting a new cut. Stylist Barry suggests, "It's best to avoid blunt bangs and lots of layers because they only accentuate a heavier face." Nikki explains, "Wearing hair straight, at shoulder length or a little longer, can help create the illusion of a slender face." Pregnancy Hair: Conquer curls without chemicals. If your hair isn't naturally straight and you have the time and energy for heat styling, go for it. Prep damp hair by combing through a dollop of straightening balm. Then blow dry with a round, natural-bristle brush, being careful to point the nozzle down the hair shaft, to ensure a smooth finish. If you prefer to keep your curls intact, just run a light-hold gel through towel-dried hair to keep frizzies in check. Pregnancy Hair: Go low-maintenance. Once you've given birth you probably won't have much free time, let alone 15 minutes to wash your hair and primp. This is reason enough to get a cut that you don't have to style every day. Stylist Shirley Ching notes that few women have the time to come in for regular cuts when they're toting a baby, so she recommends longer styles as being easier to maintain. Hair that can be pulled back is best, advises stylist Ramona. This is especially true when your baby is grabbing anything she can get her hands on. Good news — ponytails are chic and practical. Slick hair back into a low ponytail with a leather cord or ribbon wrapped around the elastic for an updated look." Source and further information: http://health.discovery.com/centers/pregnancy/americanbaby/hair.html Further information: "Cutting hair while pregnant": http://www.bubhub.com.au/community/forums/showthread.php?t=13338&page=2 "Hair care during pregnancy" http://www.askbaby.com/hair-care-during-pregnancy.htm "16 wks - Can I colour my hair" http://www.pregnancy-info.net/QA/answers-16_wks__Can_I_colour_my_hair__/

It's ok to do anything to your hair when you are pg as long as you are safe. I have heard though that sometimes perms don't take because of hormones, personally mine took better. After you have a baby you will lose a lot of hair from hormones so maybe now is a good time;)