Preconception Care

September 23, 2011

Preconception care is the promotion of the health and well-being of a woman and her partner before pregnancy. The optimal time to identify, manage, and treat many potential pregnancy conditions and complications is before pregnancy occurs. The goal of a preconception office visit with a primary care doctor is to identify and assess those medical and social conditions that may put the mother and her baby at risk. The benefits of intentionally preparing for a pregnancy relate to the important and critical period of fetal organ development that occurs in the first 10 weeks after fertilization. The traditional first prenatal visit is too late to impact on pregnancy complications impacted by prescription and nonprescription drugs, alcohol, and poor diet.

THE PRECONCEPTION HISTORY

The primary care physician will want to approach the preconception evaluation systematically. A woman should come to a preconception office visit prepared to discuss the following aspects of their health history:

  • Medications
  • Exposure to possible toxins
  • Age, family history, and genetic disorders
  • Infections and immunizations
  • Social habits
  • Diet and exercise
  • Any chronic illnesses

Medications

A key challenge is to identify those medications and chemicals that are potentially harmful to the fetus before conception and discourage their use during the preconception and early pregnancy periods. All current prescription and nonprescription medications as well as herbal supplements must be reviewed.

Work, Home, and Hobby—Exposure to Toxins

Many toxic exposures are teratogenic (damaging to the fetus), including occupational exposure to organic solvents, anesthetic gases, and antineoplastic agents. Women planning a pregnancy should minimize use of common household products such as paint and paint removal products, bleaches, lye, and oven cleaners. There is no convincing evidence of adverse pregnancy outcomes for women exposed to common sources of electromagnetic field radiation, such as office and home computer use, electric blankets, and heated waterbeds.

Age, Family History, and Genetic Disorders

Many women are postponing pregnancy because of educational and career goals, therefore advanced maternal age is becoming more common. The older woman is more likely to have concerns about chromosomal abnormalities and infertility as well as an increased likelihood of chronic medical illness. Advanced maternal age contributes to the risk of chromosomal abnormalities, as does advanced paternal age over 60. The preconception period is the perfect opportunity to educate parents about a woman’s fertility “biologic time clock” (particularly after the age of 35 years), and the purposes and techniques of prenatal diagnosis. A detailed review of the woman’s family history and ethnicity for genetic disorders (for such disorders as cystic fibrosis, sickle-cell anemia, and Tay-Sachs disease) and malformations (such as neural tube defects) is important during a preconception office visit. A genetic counselor or maternal-fetal specialist may need to be seen if there is a personal or family history of a child with a potential genetic disorder, or advanced maternal age.

Infections and Immunizations

Hepatitis B is the most common type of hepatitis in the United States. Risk factors for hepatitis B include multiple sexual partners, sexually transmitted diseases, blood transfusions, and intravenous drug abuse in both the patient and her sexual partner. All women should be screened for hepatitis B, and those patients at high risk should have more detailed testing. Most women who might transmit the HIV infection to their fetus are asymptomatic. Vertical transmission (from mother to baby) results in approximately a 25% chance of fetal infection from an untreated HIV-positive mother, a risk that can be significantly reduced with preconception or early pregnancy treatment. During the preconception period, women should be educated about high-risk behavior as well as given advice on contraception. All sexually active women should be offered HIV testing.

Toxoplasma gondii is a parasite that can cause fetal growth retardation and congenital anomalies. Approximately 30% of adults in the United States have serologic evidence of prior exposure. Screening is controversial because evidence that treatment prevents congenital disease is lacking. Patients can reduce their risk by avoiding the high-risk practices of eating raw or uncooked meat, changing cat litter, and failing to wash kitchen knives after preparing raw meat products.

Congenital cytomegalovirus (CMV) infection occurs in 1% of all live births in United States, and causes major neonatal illness in 5-10% of these cases. Most congenital CMV is a result of a primary (first time) infection during pregnancy. No specific recommendations for health care and day care workers have emerged, other than universal precautions—thorough hand washing and use of protective gloves and garments. However, day care workers caring for children in the 12to 36-month age group have the highest risk of occupational CMV infection and, if seronegative (no blood evidence of antibodies as protection), may want to consider shifting their job to care for either infants or older children to reduce their exposure.

The preconception visit should include an evaluation and update of standard adult immunizations. These would include tetanus, rubella, hepatitis, and varicella (chicken pox). Finally, pregnancy is considered a highrisk condition for influenza. Women expected to be at least 3 months pregnant during the influenza season (November to April) should be vaccinated.

Social Habits

A woman’s psychosocial and mental health can have a significant impact on a pregnancy. Ongoing use of alcohol, tobacco, and illicit drugs should end due to the risks to the woman and her future baby. Unfortunately, approximately a third of women in the United States drink alcohol during their pregnancy. However, even modest amounts of alcohol consumption during pregnancy can cause persistent neurobehavioral deficits in children. Approximately 18% of pregnant women report smoking tobacco and will be at risk for such complications as abruptio placentae (placental abruption and bleeding), preeclampsia (toxemia), and preterm labor.

Diet and Exercise

A balanced diet, along with the achievement or maintenance of an ideal body weight improves pregnancy outcomes. Women with eating disorders should be evaluated and treated prior to pregnancy. Most general diets, including vegetarianism, will be safe during pregnancy. More restrictive diets, such as lactovegetarians (who eat no eggs) and vegans (who eat only plants), will require supplementary calcium, zinc, iron, and vitamins B and D. High-dose vitamin supplements should be avoided. Daily folic acid intake of 0.4 mg should begin at least 1 month prior to pregnancy and continued through the first trimester. For women who have had a child with a neural tube defect, a higher dose of folic acid (4.0 mg) is recommended and has been shown to decrease the recurrence rate of neural tube defects. The Food and Drug Administration has recently warned that women who may become pregnant, and those pregnant and lactating, should avoid certain fish (such as shark, swordfish, and king mackerel) because of methyl mercury. This form of mercury can cause harm to the developing fetal nervous system.

The current evidence continues to demonstrate marked benefit to both the mother and fetus for women who exercise during pregnancy. The current recommendation is for women to continue their prepregnancy activity level when they become pregnant. Specific guidelines for maximum heart rate ranges during pregnancy should be discussed.

Chronic Illnesses

The woman contemplating a pregnancy who has a chronic illness should seek the advice of her physician. Examples of such illnesses include asthma, high blood pressure, and heart and kidney disease. The physician’s goal will be to optimize the health status for the existing illness prior to pregnancy, and alert the woman to any additional risks.

SEE ALSO: Diet, Exercise, Immunization, Pregnancy, Prenatal care, Toxoplasmosis

Suggested Reading

  • Frey, K. A. (2002). Preconception care by the nonobstetrical provider. Mayo Clinic Proceedings, 77(5), 469—473.
  • Frey, K. A. (2002). Preconception care. Primary Care Reports, 5(25), 222-227.

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