Obstetrics / Prenatal Care

• Prenatal care is generally provided to individual women by midwives, obstetrician-gynecologists, or family medicine clinicians. Group prenatal care is an appealing alternative for some women. Referral to a Maternal-Fetal Medicine specialist is appropriate for women with chronic health conditions, women who have experienced pregnancy complications in the past, and women who develop complications during their current pregnancy.
• One goal of prenatal care is identification of women at increased risk of medical complications, pregnancy complications, or fetal abnormalities.
• If the woman has risk factors for ectopic pregnancy (eg, history of ectopic pregnancy or pelvic infection), early identification of the location of the pregnancy is important.
• Routine early (before 20 weeks of gestation) ultrasound examination provides better estimation of gestational age than menstrual dates, resulting in significantly reduced frequency of labor induction for post term pregnancy and use of tocolysis for suspected preterm labor. Early ultrasound examination can lead to earlier detection of clinically unsuspected fetal malformations and multiple pregnancy
• The American College of Obstetricians and Gynecologists (ACOG) recommends offering all women aneuploidy screening before 20 weeks of gestation and giving all women the option of having a diagnostic invasive procedure (genetic studies on samples obtained by chorionic villus biopsy or amniocentesis) instead of screening, regardless of maternal age. Screening tests fall into two categories: (1) assessment of maternal serum levels of specific biochemical markers associated with Down syndrome, with or without assessment of specific ultrasound markers and (2) assessment of cell-free DNA in the maternal circulation. Either approach is acceptable as long as the patient receives appropriate pretest genetic counseling to make an informed choice. The cost to the patient can differ substantially depending on the approach and is another factor for the patient to consider.

• ACOG considers ethnic-specific, panethnic, and expanded carrier screening acceptable strategies for offering prenatal carrier screening. For all women, they recommend offering carrier screening for cystic fibrosis and spinal muscular atrophy, and a complete blood count (CBC) for screening for thalassemias and hemoglobinopathies.

Fragile X premutation carrier screening is recommended for women with personal or family risk factors for the disease. Consanguineous couples should be offered genetic counseling to discuss the increased risk of recessive conditions in their offspring.

 

The following tests are performed on all pregnant women:

• Rhesus type and red cell antibody screen
• Hematocrit/hemoglobin and mean corpuscular volume
• Documentation of immunity to rubella and varicella
• Qualitative assessment of urine protein
• Assessment for asymptomatic bacteriuria. We suggest urine culture.
• Cervical cancer screening according to standard guidelines
• Testing for syphilis, hepatitis B antigen, and chlamydia
• Opt-out approach to human immunodeficiency virus testing