Maternity Care Update: Prenatal Care and Specific Conditions.

Early initiation of prenatal care is associated with improved health outcomes for women and newborns. An essential element of prenatal care is determining the estimated due date, ideally using a first-trimester ultrasound. Laboratory tests should be obtained to screen for conditions that can affect pregnancy. Routine immunizations for all pregnant women include influenza vaccine; tetanus toxoid, reduced diphtheria, acellular pertussis (Tdap) vaccine. All women should be screened for gestational diabetes mellitus in midpregnancy. Women with risk factors also should be screened in the first trimester. Aspirin (ie, 60 to 150 mg/day) starting at 12 to 16 weeks reduces the risk of preeclampsia for women at high risk. Chronic medical conditions should be managed according to guidelines to promote optimal control. Women with such conditions may require testing in the late third trimester. Induction of labor may be offered to these women before 41 weeks, based on the condition and relative risks and benefits of continued pregnancy. Women without maternal or fetal indications should not be offered elective delivery before 39 weeks, but should be offered induction at 41 weeks with a recommendation for delivery before 42 weeks.