WHAT TO EAT WHEN TRYING TO CONCEIVE

A growing body of evidence suggests what women eat influences conception and pregnancy outcomes. While women become pregnant on a variety of diets, nutri­ent-rich, plant-based eating patterns are associated with a greater likelihood for conception. In the Nurses’ Health Study II, women who ate more of certain foods and sup­plements experienced a lower rate of ovulatory disorder infertility, one of the leading causes of infertility in wom­en. Regardless of weight, age, and parity, consuming more of these items seemed beneficial: vegetable protein sourc­es, monounsaturated fats rather than trans fats, low gly­cemic carbohydrates, full-fat dairy foods, multivitamins, iron from plant foods, and from dietary supplements that contain iron.¹

It is possible that in addition to providing nutrients nec­essary for well-being, plant-based diets with adequate calories help promote a healthier weight. Obesity (body mass index of 30.0 and above) has been associated with reduced female fertility, and time to conception appears to increase with increasing body weight.² Maternal obesity also increases the risk for gestational hypertension and diabetes, cesarean delivery, and heart and neural tube defects (NTDs).³

Must-Have Preconception Nutrients

Folate/folic acid

Adequate folate helps reduce the risk for NTDs during the first month of pregnancy, often when a woman does not realize she is pregnant. Women of childbearing age are advised to consume 400mcg daily of folic acid from dietary supplements and/or enriched grains, and to include folate-rich foods, such as edamame and spinach.⁴

Iron

About 10% of non-pregnant women ages 15–49 years living in the U.S. have iron deficiency.⁵ Lower iron stores at conception are associated with increased risk for iron-deficiency anemia in pregnancy, which increases chances for preterm delivery and low-birthweight infants. Women should regularly consume sources of iron, such as meat, tofu, and fortified grains, and take an iron sup­plement if necessary, to get the suggested 18mg/day prior to pregnancy.⁶

A daily multivitamin/multimineral supplement with 100% of the Daily Value for folic acid, iron, and other nutrients help to bridge nutrient gaps. A statistical analysis of 41 studies suggests a link between multivitamin use and reduced risk of NTD, heart and limb defects, and cleft palate.⁷ Research also suggests multivitamin use may decrease risk for preterm delivery.⁸

What to Limit and Avoid Prior to Pregnancy

Caffeine

Observational studies have linked caffeine, found in beverages and certain food and medications, with mis­carriage. Currently there is insufficient evidence from randomized controlled trials to recommend completely avoiding caffeine before, and during, pregnancy. Women trying to conceive should limit caffeine consumption to 200mg per day, about the amount in 12oz of coffee and four 12-oz servings of sugary or diet soda, such as cola and soft drinks with added caffeine.⁹

Alcohol

Experts suggest abstaining from alcohol when trying to conceive as women may become pregnant and not know they are expecting for up to 6 weeks. Alcohol can cause irreversible damage to the central nervous system and may result in miscarriage.¹⁰ 

References

1. Chavarro, JE, Rich-Edwards, JW, Rosner, BA, Willett WC. Diet and lifestyle in the prevention of ovulatory disorder infertility. Obstet Gynecol. 2007; 110: 1050–1058.
2. Stang, J, Huffman, L. Position of the Academy of Nutrition and Dietetics: Obesity, Reproduction, and Pregnancy Outcomes. J Acad Nutr Diet. 2016;116(4): 677–691.
3. U.S. Department of Health & Human Services. Office on Women’s Health. Weight, fertility, and pregnancy. December 27, 2018. https://www.womenshealth.gov/healthy-weight/weight-fertility-and-pregnancy
4. Centers for Disease Control and Prevention. Folic acid. April 11, 2018. https://www.cdc.gov/ncbddd/folicacid/about.html
5. Gupta, PM, Hamner, HC, Suchdev, PS, Flores-Ayala, R, Mei, Z. Iron Status of Toddlers, Nonpregnant Females, and Pregnant Females in the United States. Am J Clin Nutr. 2017;106(Suppl):1640S–1646S
6. U.S. Department of Health & Human Services. Iron fact sheet for health professionals. October 16, 2019. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional
7. Goh, IG, Bollano, E, Einarson, TR, Koren, G. Prenatal multivitamin supplementation and rates of congenital anomalies: a meta-analysis. J Obstet Gynaecol Can. 2006;28(8):680-689.
8. Vahratian, A, Siega-Riz, AM, Savitz, DA, Thorp, JM. Multivitamin use and the risk of preterm birth. AJE. 2004;160:9(1):886–892.
9. American College of Obstetrics and Gynecology. ACOG Committee opinion no. 462: Moderate caffeine consumption during pregnancy. Obstet Gynecol. 2010;116:467–468.

Centers for Disease Control and Prevention. Fetal alcohol syndrome disorders (FASDs). March 29, 2019.  https://www.cdc.gov/ncbddd/fasd/faqs.html