II. Epidemiology
- Risk of Congenital Anomaly if low risk mother: 2-4%
III. Timing:
- All women of childbearing age
- Routine Health Maintenance exams
- Following negative Pregnancy Test
- Treatment for Sexually Transmitted Disease
V. Pathophysiology
VI. History: Obstetrical and Menstrual
- Anovulatory Bleeding (Metrorrhagia)
-
Infertility history
- More than 6 months of actively trying to conceive
- Contraception History
-
Recurrent Pregnancy Loss
- Couples with history of pregnancy loss
- Ultimately 70-80% will have a successful pregnancy
- Evaluation for 2-3 prior Spontaneous Abortions
- Karyotype
- Balanced chromosomal Rearrangements
- Translocations or Inversions
- Lupus Anticoagulant
- Activated Partial Thromboplastin Time (PTT)
- Kaolin Clotting time
- Karyotype
- Couples with history of pregnancy loss
-
Preterm Labor (Pursue correctable factors)
- Cervical incompetence
- Uterine anomalies
- Maternal infections
- Birth defects
- See Pregnancy Risk Assessment for ethnic risks
- Cystic Fibrosis
- Nonsyndromic Hearing Loss
VII. History: Medical
-
Systemic Lupus Erythematosus
- High fetal loss rate, esp. with high SLE activity
- Clowse (2005) Arthritis Rheum 52:514-21 [PubMed]
-
Diabetes Mellitus
- See Diabetes Mellitus Preconception Counseling
- Avoid ACE Inhibitors, Angiotensin Receptor Blocking Agents (ARB), and Statin agents
- Metformin may be continued, but other oral antiantidiabetic medications should be discontinued
- Optimize Blood Glucose control with goal Hemoglobin A1C <7%
- Hyperglycemia is Teratogenic in first 12 weeks
- Start Insulin as indicated
- Monitor for Hypoglycemia (be aware of decreased Hypoglycemia awareness)
- Observe for Diabetic Ketoacidosis
-
Bariatric Surgery
- Avoid pregnancy in the first 18 months after Bariatric Surgery
- Allow for weight loss and nutritional status to stabilize prior to pregnancy
- Increased risk of Internal Hernia following Bariatric Surgery
- Internal Hernia is especially more common in first 18 months following Bariatric Surgery
- Unexpected pregnancy is more common
- Oral Contraceptive absorption is reduced and fertility improves with weight loss
- Nutritional deficiency is common in Bariatric Surgery
- Deficiencies include Vitamins A, B1, B6, B9, B12, C, D, E, K and iron
- Check standard Bariatric Surgery labs at recommended intervals (as for non-pregnant patients)
- Supplements recommended prior to pregnancy and continue throughout pregnancy
- Multivitamin 2 daily
- Iron 65 mg daily (in addition to Multivitamin)
- Folic Acid 400 mcg (600 Dietary Folate Equivalents or DFE) daily
- Vitamin D 400-800 mcg daily
- Vitamin B12 350 mcg daily
- Avoid pregnancy in the first 18 months after Bariatric Surgery
-
Obesity (BMI >27-30 kg/m2)
- Obesity general risks
- Risk for Gestational Diabetes and Hypertension
- Higher risk for Fetal Macrosomia (associated with Shoulder Dystocia, operative delivery)
- Higher risk for Neural Tube Defect, IUGR, congenital anomalies, Spontaneous Abortion and Stillbirth
- Associated Neural Tube Defect (NTD) Risk
- Weight 80-90 kg: NTD Relative Risk 1.9 fold
- Weight over 100 kg: NTD Relative Risk 3 fold
- Obesity general risks
- Underweight (BMI<18.5 kg/m2)
- Associated with nutritional deficiency and infants with Gastroschisis
- Evaluate for Eating Disorders prior to pregnancy
- Evaluate for food insecurity
- Chronic Hypertension
- See Hypertension in Pregnancy
- See Anti-Hypertensive Medications in Pregnancy
- Maternal Hypertension is associated with preterm birth, Placental Abruption, IUGR, PIH and fetal death
- Antihypertensives safe in pregnancy
- Avoid agents associated with congenital defects
- ACE Inhibitors
- Angiotensin Receptor Blocking Agents
- Thiazide Diuretics
- Atenolol (associated with IUGR)
-
Epilepsy
- See Epilepsy in Pregnancy
- Associated with 4-8% risk of congenital anomalies
- Folic Acid supplementation at 1000 to 4000 mcg daily starting 1-3 months before pregnancy
- Avoid Valproate, Phenytoin, Carbamazepine and Phenobarbital in pregnancy due to Teratogenicity risk
- Attempt to decrease antiepileptics to a single safe agent, at the lowest effective dose
- Seizures worsen during pregnancy in as many as one third of patients
-
Deep Vein Thrombosis (DVT) or other Thromboembolism (or Thrombophilia)
- Risk of recurrence in pregnancy 7 to 12%
- Test for Thrombophilia
- Consider Low Molecular Weight Heparin in pregnancy
- Avoid Warfarin (Teratogenic)
- Major Depression
-
Anxiety Disorder
- Avoid Benzodiazepines (associated with Cleft Lip and Palate)
-
Asthma
- See Asthma in Pregnancy
- Inhaled Corticosteroids should be continued
- Optimize Asthma Management to minimize the risk that oral Corticosteroids will be needed
- Oral Corticosteroids are associated with IUGR, Cleft Palate and Preeclampsia risk
- Use oral Corticosteroids when the risk of Severe Asthma to mother and fetus exceeds that of Corticosteroid risk
- Acne Vulgaris
-
Hypothyroidism
- See Hypothyroidism
- See Levothyroxine for dosing protocol
- Complicates 1 to 3 per 1000 pregnancies in U.S.
- Associated with fetal loss, Stillbirth, Preeclampsia, and IUGR
- Avoidance of uncorrected Hypothyroidism in Pregnancy is critical
- Obtain endocrinology Consultation
- Check Thyroid Stimulating Hormone (TSH) at earliest pregnancy diagnosis
- Increased dose required from earliest diagnosis of pregnancy until delivery
- Anticipate increasing dose by 30% as early as 4-6 weeks Gestational age
- Decrease dose to baseline immediately after delivery, and recheck TSH in 6-8 weeks
- Recheck TSH every trimester at minimum
-
Hyperthyroidism
- Complicates 2 in 1000 pregnancies
- Associated with Miscarriage, preterm delivery, Preeclampsia, IUGR, CHF and Thyroid Storm
- First trimester: Propylthiouracil (PTU)
- Switch to Methimazole after first trimester due to hepatotoxicity risk with PTU after first trimester
- Methimazole should be avoided in first timester due to possible Teratogenicity during that trimester
- Second trimester: Methimazole (Tapazole)
- Third trimester: Methimazole (Tapazole)
- Miscellaneous conditions with an impact on pregnancy
- Phenylketonuria (PKU)
- Congenital Heart Disease (and other cardiac disease)
- Chronic Kidney Disease
- Hemoglobinopathies
- Cancer
- Intimate Partner Violence (physical abuse)
VIII. History: Medications
- See Medications in Pregnancy
- Switch chronic medications with risk (Class D or X) to safer medications prior to conception
- Reduce medications to the lowest dosages and continue only the ones with significant benefit
IX. History: Advanced Maternal Age-Related Risks
- Chromosomal Abnormalities
- Trisomy 13
- Trisomy 18
- Trisomy 21
- Age associated risk
- Age 35 year old Risk: 1 per 200 pregnancies
- Age 45 year old Risk: 1 per 20 pregnancies
- Diagnostic options
- Chorionic Villus Sampling: 9-11 weeks
- Early Amniocentesis: 12-14 weeks
- Traditional Amniocentesis: 15-16 weeks
- Fetal Blood Sampling: 2nd-3rd trimester
- Advanced Paternal Age
- Maternal age risk doubled if father's age >55 years
X. History: Family related risk (consider genetic counselor if positive history)
- Cystic Fibrosis
- Congenital Heart Disease
- Hemophilia
- Fragile X Syndrome
- Phenylketonuria (PKU)
- Dwarfism
- Spina bifida
- Limb abnormalities
- Duchenne Muscular Dystrophy
- Myotonic Dystrophy
XI. History: Ethnicity (screen parents for carrier status)
-
Sickle Cell Trait (screen with sickle cell smear)
- Black
- Indian
- Middle Eastern Descent
- Alpha or beta-Thalassemia (Screen for MCV<70)
- Southeast Asian (Laotian, Cambodian, Hmong, Thai)
- Mediterranean
- Black
- Indian
- Middle Eastern
- Ashkenazi Jewish Descent (East European)
- Recommended by ACMG and ACOG
- Tay-Sachs Disease (1/31 carrier rate, also seen in French Canadians)
- Canavan Disease (1/40 carrier rate)
- Recommended by ACMG (American College of Medical Genetics Genomics)
- Gaucher Disease (1/18 carrier rate)
- Niemann-Pick Disease Type A (1/90 carrier rate)
- Mucolipidosis IV (1/127 carrier rate)
- Additional conditions to consider screening per ACOG (American College of Obstetricians Gynecologists)
- Familial Hyperinsulinism (1/52 carrier rate)
- Glycogen Storage Disease Type 1 (1/71 carrier rate)
- Maple Syrup Urine Disease (1/81 carrier rate)
- References
- Recommended by ACMG and ACOG
XII. History: Teratogen Exposure
- See Teratogen Exposure
- Includes Occupational Exposures in Pregnancy
- Includes Herbal Teratogens
- See Nutrition in Pregnancy
- Includes food Teratogens
- See Mercury Content in Fish
- See Radiation Exposure in Pregnancy
- See Medications in Pregnancy
- See Substance Abuse in Pregnancy
XIII. References
- Wilkins in Ryan (1999) Kistner's Gynecology, p. 451
- Brundage (2002) Am Fam Physician 65(12):2507-14 [PubMed]
- Farahi (2013) Am Fam Physician 88(8): 499-506 [PubMed]
- Johnson (2006) MMWR Recomm Rep 55(RR-6): 1-23 [PubMed]
- Kruszka (2019) Am Fam Physician 99(1): 25-32 [PubMed]
- Leuzzi (1996) Med Clin North Am 80:337-74 [PubMed]
- Morrison (2000) Prim Care 27(1):1-12 [PubMed]
- Ramirez (2023) Am Fam Physician 108(2): 139-50 [PubMed]