(CBS) -- It is the first question people ask new parents. But as WBBM's Steve Miller reports, for one birth in 4,500, there is no clear answer: Is it a boy or a girl?
When Dr. Earl Cheng of Lurie Children's Hospital enters the picture, it's usually after parents have heard the news in the delivery room.
"When they're told, 'We don't know whether you have a boy or a girl.' And they want an immediate answer."
In the past, parents and surgeons have made a quick decision.
"Once you make that decision, the surgeon comes in and acts very quickly to take out all the tissue that's discordant with what the decision was, and they reconstruct and make it consistent with the gender of choice.
"Well, you've done some things that are essentially irreversible. And what we've found is that, if you made the wrong decision - with what the person perceives as later in life - then you potentially have a problem."
But Dr. Cheng says parents have been pressured to decide: boy or girl, to do the surgery - and don't look back to avoid the shame of telling people they have an intersex child.
"If you were born and only had one leg - now that's probably a pretty rare event - but you'd have no problem telling anyone, saying, 'Oh my child was born without one leg.'
"...But you'd have a really problem saying, 'My child was born with both a vagina and a penis.'
Coming up in the next parts of this series, we'll hear four stories: two families of newborns and two adults not male or female.
Lurie Children's Hospital is one of the medical centers in the Chicago area that treats patients with a variety of disorders of sexual development.
The DSD clinic estimates that 1 in every 4,500 children has a disorder of sexual development, although other estimates range from 1 in 1,500 to 1 in 5,000.
Lurie's DSD clinic currently treats 72 patients.
For more information on Lurie's DSD Clinic, click here.
Parents we spoke with for this series recommended the website www.dsdfamilies.org.
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