Q. I'm 22 and want to get pregnant later this year. Are there things I should be doing now for my baby's health?

A. You're an akamai young lady! There are things you can do to create the best possible situation for having a healthy baby.

Folic acid: It turns out that brain and spinal-cord growth (so-called neural tube development) in early pregnancy requires folic acid (a B vitamin). A great deal of growth is already complete four weeks after your first missed period. This is eight weeks after conception, often before you even know you're pregnant. If during these first eight weeks you don't get enough folic acid, then permanent neural tube defects such as stunted brain growth, mental retardation and the spinal-cord defect called spina bifida can result.

And because so many pregnancies are unplanned, all women, even if not pregnant, should be taking vitamins containing at least 0.4 mg (400 micrograms) of folic acid daily throughout their childbearing years. This would reduce the chance of neural-tube birth defects by two-thirds. But because the effects of high folate doses are not well known and complicates diagnosing vitamin B12 deficiency, do not take more than 1 mg a day. A 2002 survey showed that only 20 percent of women knew that folic acid could prevent birth defects. Even fewer knew they had to start taking folic acid before getting pregnant.

Curbing disease: Sexually transmitted diseases can lead to developmental disabilities, mental retardation and blindness in your baby, and chronic pelvic pain or infertility in you, so get screened for STDs and HIV.

If you're overweight, get tested for diabetes, because infants of diabetics have three times the chance of birth defects, and reducing blood sugars before and during pregnancy by losing weight, exercising and perhaps taking insulin will substantially reduce birth defects.

Maintain weight: Getting to a healthy weight before pregnancy reduces neural-tube defects, premature delivery, diabetes, C-sections, high blood pressure and dangerous blood clots.

Get immunized: See if you need a rubella shot to prevent birth defects and deafness. All women under age 19 and women over 18 who are at high risk of contracting hepatitis B should make sure they've been immunized against hepatitis B to prevent liver failure, cancer or cirrhosis in themselves or their children. And if you're on daily medication, see your doctor, as some medications may be changed to safer alternatives that don't cause birth defects.

Quit smoking: Stopping smoking before pregnancy prevents premature birth, low birth weight and other problems. And curtailing alcohol consumption will prevent fetal alcohol syndrome and other birth defects.

You may have saved many keiki from brain damage by your query. And doctors need to ask every woman whether she intends to become pregnant in the next year to tell them the information in this column.

Dr. Landis Lum is a family-practice physician for Kaiser Permanente and an associate clinical professor at the University of Hawai'i's John A. Burns School of Medicine. Send your questions to Prescriptions, Island Life, The Advertiser, P.O. Box 3110, Hono-lulu, HI 96802; fax 535-8170; or write islandlife@honoluluadvertiser.com. This column is not intended to provide medical advice.