More tips for a healthy pregnancy.

In addition to good nutrition, here are some other ways you can help ensure a healthy pregnancy.

* Exercise

Obstetricians encourage regular, mild aerobic exercise 15 minutes per day and at least three days a week during pregnancy. The type and amount of exercise your body is accustomed to before you conceive is generally acceptable during pregnancy. So you'll want to start now with the exercise program you intend to continue after conception.

Hormonal changes during pregnancy will result in lax connective tissue and looser joints, making you more susceptible to strains and sprains. High-impact exercise, therefore, is not recommended. Because of a growing uterus, your sense of balance may be altered. These body changes need to be considered when choosing a preconception exercise program. Walking and swimming are two excellent forms of exercise during pregnancy. Bicycling is also good if your sense of balance remains trustworthy.

* Pre-physical

Establish a relationship with a physician and/or certified nurse-midwife before conception. Schedule an appointment for a physical, including a Pap smear. Your physician may want to check your rubella titer to determine if you need a rubella vaccination. (Rubella exposure during pregnancy has resulted in serious birth defects.) You'll want to explore your health and genetic history, as well as your spouse's. Describe your working conditions to your health-care professional to uncover any hazards.

* Environment

Of all birth defects, 10 percent are caused by known environmental factors, 25 percent are from genetically related causes, and 65 percent are from unknown causes. Environmental hazards have increased the incidence of miscarriages, stillbirth, and deformities in infants. Most susceptible are mothers who are exposed to a hazard in large amounts for a long time or during the most vulnerable time in the developing infant's life (14 to 56 days after conception). While we must continue to eat, breathe, and work, an examination of your workplace, your spouse's workplace, and your home for the red flag offenders may make the difference between health and unhealthy development of your baby.

Three types of environmental hazards threaten reproduction: physical, biological, and chemical, with chemicals resulting in the most severe defects. Approximately 50,000 chemicals are used in today's industry, and 500 of them are known to affect reproduction. Examples include pesticides, herbicides, factory fumes of all kinds, anesthetic gases, lead, solvents, and cigarette smoke. These chemicals harm not only women but also men by mutating the DNA makeup of sperm. Employers are required by law to provide information to employees about the hazards in their workplace and recommend safety measures. Obtain a copy of this information from your employer, if applicable, and share it with your physician. An occupational nurse may also have valuable information.

Physical hazards include strenuous lifting, long periods of standing, hot environments, radiation, and high levels of noise. X-ray exposure should be avoided during childbearing years, and a lead apron should be worn if a nonpregnant woman requires an X-ray. Plan a dental checkup well before conception.

The radiation from computers and other video display terminals is currently under great debate. Some studies indicate that low and very low electromagnetic frequencies alter hormonal secretions, interfere with intracellular activities, adversely affect the immune system, and cause a higher risk of miscarriage. If your job requires you to be in front of a computer, sit an arm's length away from the monitor screen and take frequent breaks.

Biological hazards include toxoplasmosis, genital herpes and other venereal diseases, viruses, hepatitis, and bacteria. If you have had any type of sexually transmitted disease, let your physician know. Toxo-plasmosis is contracted by eating raw or partially raw meat, or through exposure to cat droppings. If you have a litter box in your house, make arrangements for someone else to empty it before you begin trying to conceive.

* Personal habits

Years of research have resulted in appropriate warnings about the effects of alcohol, recreational drugs, and cigarette smoking on the unborn in terms of miscarriage, stillbirth, deformities, low birth weight, premature birth, addiction and withdrawal symptoms, and mental retardation. More recent studies have shown that drugs such as cocaine are more harmful to babies than initially reported. The infant receives greater exposure to harmful substances than the mother because of the infant's small size and immature system that takes much longer to excrete the substance(s). One ounce of liquor, for example, affects a one-fourth-pound body much more than a 140-pound body. Seek help for any habit that would threaten your pregnancy.

Many over-the-counter and prescription drugs can be harmful to the unborn, including some medications for the common cold. The safest rule of thumb is to avoid all medication while trying to conceive and afterward. If medication is a necessity, consult your physician.

* Plan for a healthy lifestyle

All chemicals, hormones, and substances that pass through the placental barrier may affect the unborn, whether those substances entered from an external source or were manufactured within the body. Stress triggers the release of hormones, such as adrenaline, which increase your heart rate, alter gastric secretions, and influence other body functions. The full effect of maternal stress on the unborn is still unknown, but we do know that the infant experiences similar hormonal responses to some degree.

If possible, assign a degree of predictability now to the months ahead to decrease the stress felt by you, your family, and your unborn.

Avoid changing residences if at all possible during pregnancy. Moving is not only a physical strain but an emotional one as well, since those maternal instincts of "nesting" are strong.

In pregnancy you assume responsibility not only for your health but also the health of your child, which may determine your child's ability to achieve a state of well-being throughout his or her lifetime. God created the woman's body to give the very best to her unborn. As you live in harmony with His design and prepare now for pregnancy, a great reward will fill your arms as you gaze into the eyes of a brand-new person to whom you gave the gift of life and health.