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
show all references1. Osterman MJK, Martin JA. Timing and adequacy of prenatal care in the United States, 2016. National vital statistics reports. May 30, 2018. Accessed January 25, 2020. https://www.cdc.gov/nchs/data/nvsr/nvsr67/nvsr67_03.pdf...
2. Institute of Medicine of the National Academies. Weight gain during pregnancy: reexamining the guidelines. Report brief. May 2009. Accessed March 2019. https://bit.ly/34dQKiB
3. Fox NS. Dos and don'ts in pregnancy: truths and myths. Obstet Gynecol. 2018;131(4):713–721.
4. Kilpatrick SJ. Guidelines for Perinatal Care. 8th ed. American Academy of Pediatrics & American College of Obstetricians and Gynecologists; 2017.
5. Johansson S, Villamor E, Altman M, et al. Maternal overweight and obesity in early pregnancy and risk of infant mortality: a population-based cohort study in Sweden. BMJ. 2014;349:g6572.
6. ACOG practice bulletin no. 156: obesity in pregnancy [published correction appears in Obstet Gynecol. 2016;128(6):1450]. Obstet Gynecol. 2015;126(6):e112–e126.
7. Madjunkov M, Chaudhry S, Ito S. Listeriosis during pregnancy. Arch Gynecol Obstet. 2017;296(2):143–152.
8. Centers for Disease Control and Prevention. Prevent infections during pregnancy. Accessed April 2019. https://www.cdc.gov/features/prenatalinfections/index.html
9. Ross AC, Taylor CL, Yaktine AK, et al. Dietary Reference Intakes for Calcium and Vitamin D. National Academies Press; 2011.
10. Mun JG, Legette LL, Ikonte CJ, et al. Choline and DHA in maternal and infant nutrition: synergistic implications in brain and eye health. Nutrients. 2019;11(5):E1125.
11. Carlson SE, Colombo J, Gajewski BJ, et al. DHA supplementation and pregnancy outcomes. Am J Clin Nutr. 2013;97(4):808–815.
12. Piccoli GB, Clari R, Vigotti FN, et al. Vegan-vegetarian diets in pregnancy: danger or panacea? A systematic narrative review. BJOG. 2015;122(5):623–633.
13. Langan RC, Goodbred AJ. Vitamin B12 deficiency: recognition and management. Am Fam Physician. 2017;96(6):384–389. Accessed January 25, 2020. https://www.aafp.org/afp/2017/0915/p384.html
14. U.S. Department of Agriculture. Why take a prenatal supplement? Accessed May 13, 2019. https://www.choosemyplate.gov/moms-pregnancy-prenatal-supplements
15. ACOG committee opinion no. 650: physical activity and exercise during pregnancy and the postpartum period. Obstet Gynecol. 2015;126(6):e135–e142.
16. Mottola MF, Davenport MH, Ruchat SM, et al. 2019 Canadian guideline for physical activity throughout pregnancy. Br J Sports Med. 2018;52(21):1339–1346.
17. American College of Obstetricians and Gynecologists. FAQ119: exercise during pregnancy. July 2019. Accessed January 25, 2020. https://www.acog.org/Patients/FAQs/Exercise-During-Pregnancy
18. Davidson C; Society for Maternal-Fetal Medicine. Patient handout: activity restriction in pregnancy. Accessed January 25, 2020. https://www.contemporaryobgyn.net/sites/default/files/legacy/mm/ContemporayOBGYN/SMFM_Handout0814.pdf
19. Duckitt K. Exercise during pregnancy: eat for one, exercise for two. BMJ. 2011;343:d5710.
20. Holden SC, Manor B, Zhou J, et al. Prenatal yoga for back pain, balance, and maternal wellness: a randomized, controlled pilot study. Glob Adv Health Med. 2019;8:2164956119870984.
21. MacDonald LA, Waters TR, Napolitano PG, et al. Clinical guidelines for occupational lifting in pregnancy: evidence summary and provisional recommendations. Am J Obstet Gynecol. 2013;209(2):80–88.
22. Salas LA, Baker ER, Nieuwenhuijsen MJ, et al. Maternal swimming pool exposure during pregnancy in relation to birth outcomes and cord blood DNA methylation among private well users. Environ Int. 2019;123:459–466.
23. Duong HT, Shahrukh Hashmi S, Ramadhani T, et al.; National Birth Defects Prevention Study. Maternal use of hot tub and major structural birth defects. Birth Defects Res A Clin Mol Teratol. 2011;91(9):836–841.
24. Milunsky A, Ulcickas M, Rothman KJ, et al. Maternal heat exposure and neural tube defects. JAMA. 1992;268(7):882–885.
25. Habecker E, Sciscione A. Activity restriction in pregnancy. Contemporary OB/GYN. 2014;59(8):34–37.
26. Hansen C, Interrante JD, Ailes EC, et al. Assessment of YouTube videos as a source of information on medication use in pregnancy. Pharmacoepidemiol Drug Saf. 2016;25(1):35–44.
27. Centers for Disease Control and Prevention. Research on medicines and pregnancy. Accessed April 2019. http://www.cdc.gov/pregnancy/meds/treatingfortwo/research.html
28. Haas DM, Marsh DJ, Dang DT, et al. Prescription and other medication use in pregnancy. Obstet Gynecol. 2018;131(5):789–798.
29. Servey J, Chang J. Over-the-counter medications in pregnancy [published correction appears in Am Fam Physician. 2015;92(5):332]. Am Fam Physician. 2014;90(8):548–555. Accessed January 25, 2020. https://www.aafp.org/afp/2014/1015/p548.html
30. Thorpe PG, Gilboa SM, Hernandez-Diaz S, et al.; National Birth Defects Prevention Study. Medications in the first trimester of pregnancy: most common exposures and critical gaps in understanding fetal risk. Pharmacoepidemiol Drug Saf. 2013;22(9):1013–1018.
31. U.S. Food and Drug Administration; Center for Drug Evaluation and Research; Small Business and Industry Assistance. Drugs in pregnancy and lactation: improved benefit-risk information. January 22, 2015. Accessed May 13, 2019. http://www.fda.gov/downloads/Drugs/DevelopmentApprovalProcess/SmallBusinessAssistance/UCM431132.pdf
32. U.S. Food and Drug Administration. Pregnant? Breastfeeding? Better drug information is coming. Updated December 17, 2014. Accessed May 13, 2019. https://www.drugs.com/fda-consumer/pregnant-breastfeeding-better-drug-information-is-coming-334.html
33. Kong L, Li T, Li L. The impact of sexual intercourse during pregnancy on obstetric and neonatal outcomes: a cohort study in China. J Obstet Gynaecol. 2019;39(4):455–460.
34. Oei JL. Alcohol use in pregnancy and its impact on the mother and child [published online March 9, 2020]. Addiction. Accessed March 11, 2020. https://onlinelibrary.wiley.com/doi/abs/10.1111/add.15036
35. Sebastiani G, Borrás-Novell C, Casanova MA, et al. The effects of alcohol and drugs of abuse on maternal nutritional profile during pregnancy. Nutrients. 2018;10(8):E1008.
36. Sundelin-Wahlsten V, Hallberg G, Helander A. Higher alcohol consumption in early pregnancy or low-to-moderate drinking during pregnancy may affect children's behaviour and development at one year and six months. Acta Paediatr. 2017;106(3):446–453.
37. Pruett D, Waterman EH, Caughey AB. Fetal alcohol exposure: consequences, diagnosis, and treatment. Obstet Gynecol Surv. 2013;68(1):62–69.
38. Metz TD, Borgelt LM. Marijuana use in pregnancy and while breastfeeding. Obstet Gynecol. 2018;132(5):1198–1210.
39. Metz TD, Stickrath EH. Marijuana use in pregnancy and lactation: a review of the evidence. Am J Obstet Gynecol. 2015;213(6):761–778.
40. Bailey BA, Wood DL, Shah D. Impact of pregnancy marijuana use on birth outcomes: results from two matched population-based cohorts [published online March 5, 2020]. J Perinatol. Accessed March 11, 2020. https://www.nature.com/articles/s41372-020-0643-z
41. Li J, Zhao H, Song JM, et al. A meta-analysis of risk of pregnancy loss and caffeine and coffee consumption during pregnancy. Int J Gynaecol Obstet. 2015;130(2):116–122.
42. Chen LW, Wu Y, Neelakantan N, et al. Maternal caffeine intake during pregnancy and risk of pregnancy loss: a categorical and dose-response meta-analysis of prospective studies. Public Health Nutr. 2016;19(7):1233–1244.
43. Zhu Y, Olsen SF, Mendola P, et al. Maternal consumption of artificially sweetened beverages during pregnancy, and offspring growth through 7 years of age: a prospective cohort study. Int J Epidemiol. 2017;46(5):1499–1508.
44. Araújo JR, Martel F, Keating E. Exposure to non-nutritive sweeteners during pregnancy and lactation: impact in programming of metabolic diseases in the progeny later in life. Reprod Toxicol. 2014;49:196–201.
45. Couto AC, Ferreira JD, Rosa AC, et al.; Brazilian Collaborative Study Group of Infant Acute Leukemia. Pregnancy, maternal exposure to hair dyes and hair straightening cosmetics, and early age leukemia. Chem Biol Interact. 2013;205(1):46–52.
Copyright © 2020 by the American Academy of Family Physicians.
This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP. Contact
afpserv@aafp.org for copyright questions and/or permission requests.
Want to use this article elsewhere? Get Permissions
CME Quiz
More in AFP
Editor's Collections
Related Content
More in Pubmed
MOST RECENT ISSUE
Email Alerts
Don't miss a single issue. Sign up for the free AFP email table of contents.
