An OB/GYN explains the risks.

Former 'N Sync member Joey Fatone and wife Kelly's daughter Kloey Alexandra Fatone arrived Monday evening. During her pregnancy, Kelly was diagnosed with a rare genetic condition called Methylene-Tetra-Hydro-Folate-Reductase (MTHFR). Doctors also found blood clots in her lungs.

What is Methylene-Tetra-Hydro-Folate-Reductase? To find out, we asked momlogic's OB/GYN Dr. Suzanne Gilberg-Lenz.

Here's what she had to say:

• MTHFR is an enzyme that is involved in amino acid metabolism in the body. 
• People with MTHFR gene mutations can have a decreased ability to metabolize folic acid and other B vitamins.
• There is no consensus about whether or not MTHFR gene mutations contribute to recurrent miscarriages, but we do know that MTHFR mutations can cause elevated homocysteine, which increases the risk of blood clots.
• MTHFR does NOT increase the baby's chances of being born with Down syndrome. Down syndrome is a SPONTANEOUS genetic mutation that is not "caused" by any medical conditions and is not inherited. It is a random occurrence whose probability is increased by maternal age, as are many other spontaneous genetic mutations.
• MTHFR gene mutations are fairly common; nearly half the population of the United States may be at least heterozygous (carrying one copy) for an MTHFR gene mutation, which probably does NOT increase their risk for anything.
• Those with 2 copies of the mutation are considered to have a "rare" disease, as they number less than 200,000 in the U.S. Very few of these people actually have a severe disease, however.
• The great news is that the mutation may be overridden by consuming higher than average quantities of folic acid and B-complex vitamins.

"An important issue to raise here is that pregnancy itself, due to hormonal changes, raises the risk of blood clots forming from the average person's baseline risk by 20 times or more," explains Dr. Gilberg-Lenz. "Travel, dehydration, and a myriad of other conditions that increase risk further can lead to potentially life-threatening conditions such as deep vein thrombosis (blood clots) or pulmonary embolus (clots which break off and travel to the lungs)."

We're happy that Kelly is recovering nicely, and that Baby Kloey is happy and healthy.

Dr. Suzanne Gilberg-Lenz completed her undergraduate education at Wesleyan University and post-baccalaureate pre-med studies at Mills College. She earned her medical degree from the USC School of Medicine and has been in private practice for 9 years. She is the co-founder of Cedar Sinai Medical Center's Green Committee and lives in Los Angeles with her husband and two children.