Pregnancy Myths and Practical Tips
Am Fam Physician. 2020 Oct 1;102(7):420-426.
Patient information: Handouts on this topic are available at https://familydoctor.org/eating-healthy-during-pregnancy and https://familydoctor.org/exercise-during-pregnancy-what-you-can-do-for-a-healthy-pregnancy.
Author disclosure: No relevant financial affiliations.
For many patients, pregnancy is a highly anticipated and exciting phase of life, but it can also be anxiety provoking. Family physicians can resolve some of this anxiety and promote maternal and fetal health by making specific recommendations at prenatal visits. A daily prenatal vitamin with at least 400 mcg of folic acid and 30 mg of elemental iron should be recommended to promote neurologic and musculoskeletal fetal development. Weight gain in pregnancy should be guided by preconception body mass index. People who are underweight should gain 28 to 40 lb, those who have a normal weight should gain 25 to 35 lb, and those who are overweight or obese should gain 15 to 25 lb or 11 to 20 lb, respectively. A well-balanced diet including omega-3 fatty acids should be encouraged. Unpasteurized foods should be avoided during pregnancy because of the risk of listeriosis. Caffeine intake should be limited to 200 mg per day (about two small cups of coffee), and artificial sweeteners should be avoided. Pregnant patients should be encouraged to engage in regular cardiovascular activity for at least 150 minutes per week. Bed rest is not recommended. Sex can be continued throughout an uncomplicated pregnancy. Avoidance of alcohol and marijuana is recommended. The effects of hair dye or hair straightening products on fetal development or neonatal outcomes are unclear.
In 2016, prenatal care was initiated in the first trimester in more than 75% of pregnancies,1 providing a multitude of opportunities for family physicians to counsel these patients on the basics of a healthy pregnancy. During prenatal visits, physicians can dispel many myths about pregnancy. This article will discuss physical activity, provide recommendations for weight gain during pregnancy, review components of a well-balanced diet, discuss supplement and medication use, and dispel myths related to topics that have traditionally been taboo: sex and the use of marijuana and alcohol during pregnancy. Communicating this information in an individualized manner will promote maternal and fetal health.
SORT: KEY RECOMMENDATIONS FOR PRACTICE
| Clinical recommendation | Evidence rating | Comments |
|---|---|---|
Weight gain during pregnancy should be individualized based on prepregnancy body mass index.2–6 | C | Systematic review, cohort study, and guidelines showing that early weight gain and maternal obesity are associated with higher infant mortality |
Unpasteurized foods should not be consumed during pregnancy.7,8 | C | Practice recommendations and analysis showing poor neonatal outcomes in patients with listeriosis |
A prenatal vitamin with folic acid, vitamin D, calcium, and iron should be recommended for pregnant patients.1,3,4,9 | A | Meta-analyses and systematic reviews showing decreased fetal neural tube defects and promotion of musculoskeletal development |
Instead of routinely being given a fish oil supplement, pregnant patients should be encouraged to consume two or three servings per week of fish that contains low levels of mercury.3,11 | B | Randomized controlled trials showing that high fish consumption decreases preterm birth, observational studies showing increased neurodevelopment in children, and expert opinion/usual practice |
Pregnant patients should be encouraged to engage in moderate-intensity exercise for at least 150 minutes per week.15,16,19,20 | B | Systematic review and meta-analyses showing fewer newborn complications and maternal health benefits |
C | Case-control study showing risk of fetal alcohol spectrum disorder and lower birth weight | |
Caffeine intake should be limited to 200 mg per day during pregnancy.41,42 | A | Meta-analyses showing increased early pregnancy loss with high doses of caffeine |
A = consistent, good-quality patient-oriented evidence; B = inconsistent or limited-quality patient-oriented evidence; C = consensus, disease-oriented evidence, usual practice, expert opinion, or case series. For information about the SORT evidence rating system, go to https://www.aafp.org/afpsort.
SORT: KEY RECOMMENDATIONS FOR PRACTICE
| Clinical recommendation | Evidence rating | Comments |
|---|---|---|
Weight gain during pregnancy should be individualized based on prepregnancy body mass index.2–6 | C | Systematic review, cohort study, and guidelines showing that early weight gain and maternal obesity are associated with higher infant mortality |
Unpasteurized foods should not be consumed during pregnancy.7,8 | C | Practice recommendations and analysis showing poor neonatal outcomes in patients with listeriosis |
A prenatal vitamin with folic acid, vitamin D, calcium, and iron should be recommended for pregnant patients.1,3,4,9 | A | Meta-analyses and systematic reviews showing decreased fetal neural tube defects and promotion of musculoskeletal development |
References
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