How to Prepare for Pregnancy: 6 Steps to Take Before You Conceive

Why Preconception Care Matters More Than Most People Realize

Most organ systems in the fetus form before many women even know they are pregnant. The neural tube closes by day 28 after fertilization. The heart begins beating around day 22. These timelines mean that nutritional deficiencies, uncontrolled thyroid disease, or harmful medication exposures can do significant damage in the first weeks, well before a missed period triggers a pregnancy test.

The CDC estimates that only about 35% of women in the United States receive preconception counseling from a healthcare provider [1]. That gap is a clinical problem with measurable consequences.

The Evidence for Preconception Intervention

A 2021 systematic review published in The Lancet confirmed that preconception care programs reduced rates of neural tube defects, preterm birth, and small-for-gestational-age outcomes across multiple national cohorts [2]. The effect sizes were not trivial. Neural tube defect rates dropped as much as 70% in populations with high folic acid uptake, and gestational diabetes rates fell significantly when glycemic status was addressed before conception rather than after.

What "Preparation" Actually Means Clinically

Preparation is not simply taking a prenatal vitamin for a week and hoping for the best. It means identifying and correcting modifiable risk factors, nutritional, hormonal, infectious, pharmacological, and behavioral, during a window when intervention can actually change outcomes. The American College of Obstetricians and Gynecologists (ACOG) recommends that the preconception period be treated as a distinct healthcare phase, not as an afterthought to obstetric care [3].

Step 1: Schedule a Dedicated Preconception Visit

A preconception visit is a clinical appointment focused entirely on your health before conception, separate from an annual well-woman exam. Your provider will review personal and family medical history, update vaccinations, screen for sexually transmitted infections, assess chronic disease status, and discuss your reproductive goals.

What Happens at This Visit

Your provider will order or review:

• A complete blood count to screen for anemia
• Rubella and varicella immunity titers
• Sexually transmitted infection testing (HIV, syphilis, hepatitis B, chlamydia)
• Thyroid-stimulating hormone (TSH) level
• Fasting glucose or HbA1c if diabetes risk factors are present
• Blood pressure, BMI, and a medication reconciliation

ACOG Practice Bulletin Number 762 states: "Preconception care should be an integral part of primary care for all women of reproductive age." [3] That language is deliberate. It positions preconception care not as optional but as a standard component of routine care.

Timing the Visit Correctly

Ideally, this visit occurs three to twelve months before you plan to start trying. Three months gives enough time to correct a vitamin D deficiency, stabilize thyroid hormone levels, and taper or switch teratogenic medications. Twelve months allows for more significant interventions such as weight management, glycemic control, or treatment of a newly identified autoimmune condition [4].

Step 2: Optimize Your Nutritional Status Before Conception

Nutrition before conception sets the biochemical environment in which implantation and early organogenesis occur. Deficiencies in folate, iodine, iron, vitamin D, and omega-3 fatty acids have all been linked to adverse pregnancy outcomes in prospective cohort data.

Folic Acid: The Non-Negotiable

The MRC Vitamin Study (N=1,817) demonstrated that periconceptional folic acid supplementation reduced neural tube defect recurrence by 72% [5]. For women with no prior neural tube defect history, the U.S. Preventive Services Task Force recommends 400 to 800 mcg of folic acid daily, starting at least one month before conception [6]. Women with a prior affected pregnancy receive 4 mg daily, a tenfold increase, beginning at least one month before trying to conceive and continuing through the first trimester [6].

Folate from food alone is unlikely to meet the threshold required for adequate red blood cell folate concentrations. Supplementation is the standard of care.

Iodine and Thyroid Function

Iodine is required for synthesis of thyroid hormones T3 and T4. Mild-to-moderate iodine deficiency during pregnancy is associated with reduced child IQ scores and increased rates of pregnancy loss [7]. The American Thyroid Association (ATA) recommends that women who are pregnant, planning to become pregnant, or breastfeeding take a supplement containing 150 mcg of iodine daily [8]. Most prenatal vitamins contain iodine, but not all, check the label.

Vitamin D, Iron, and DHA

Vitamin D insufficiency (serum 25-OH-D <30 ng/mL) is present in approximately 40% of reproductive-age women in the United States [9]. Low vitamin D is associated with increased risk of preeclampsia, gestational diabetes, and preterm birth. Testing serum 25-OH-D before conception allows targeted repletion with doses typically ranging from 1,000 to 4,000 IU daily depending on baseline levels [9].

Iron-deficiency anemia affects roughly 10% of women of reproductive age and increases risk of preterm delivery and low birth weight [10]. A baseline CBC and ferritin level guides whether dietary changes alone or supplemental iron (typically 18 to 27 mg daily for prevention, 60 to 120 mg daily for treatment) is needed [10].

Docosahexaenoic acid (DHA), an omega-3 fatty acid, is incorporated into fetal brain and retinal tissue beginning in the second trimester. A Cochrane review of 70 trials found that omega-3 supplementation in pregnancy reduced preterm birth before 37 weeks by 11% [11].

Step 3: Screen and Treat Thyroid Disease Before You Conceive

Thyroid disease affects approximately 5 to 10% of women of reproductive age, and a large proportion of cases are undiagnosed [12]. Both hypothyroidism and hyperthyroidism carry specific risks in pregnancy that are substantially reduced when the condition is identified and controlled before conception.

Hypothyroidism and Pregnancy Risk

Overt hypothyroidism (elevated TSH with low free T4) in pregnancy is associated with miscarriage, placental abruption, preeclampsia, impaired fetal neurological development, and stillbirth [13]. Subclinical hypothyroidism, defined as TSH above the trimester-specific reference range with normal free T4, is associated with increased miscarriage rates in several prospective studies, though the evidence for treatment benefit in this group is more nuanced [13].

The ATA 2017 guidelines on thyroid disease in pregnancy recommend a TSH target of 0.5 to 2.5 mIU/L before conception for women with known hypothyroidism [8]. Women on levothyroxine should have their dose confirmed as appropriate at a preconception visit, since thyroid hormone requirements increase by approximately 25 to 30% during pregnancy [8].

Hyperthyroidism and Antithyroid Medications

Uncontrolled hyperthyroidism in pregnancy raises risk of fetal growth restriction, preterm labor, and thyroid storm [14]. Propylthiouracil (PTU) is generally preferred over methimazole in the first trimester due to methimazole's association with embryopathy, including aplasia cutis and choanal atresia [14]. Women with Graves disease who are planning pregnancy should discuss timing of conception relative to treatment with their endocrinologist, since definitive treatment (radioactive iodine or surgery) before conception may be preferable to managing active disease during the first trimester [14].

Thyroid Antibodies and Euthyroid Women

Women who are euthyroid but positive for thyroid peroxidase antibodies (TPO-Ab) have a miscarriage rate approximately two to three times higher than TPO-Ab-negative women [15]. A 2019 randomized controlled trial published in NEJM (N=952) found that levothyroxine therapy in euthyroid women with recurrent miscarriage and positive TPO antibodies did not significantly reduce miscarriage rates compared with placebo, with miscarriage rates of 28.2% versus 29.1%, respectively [16]. Routine levothyroxine in euthyroid TPO-Ab-positive women is therefore not currently recommended by major guidelines, though monitoring TSH throughout pregnancy remains appropriate [8].

Step 4: Review Every Medication for Teratogenic Risk

Not every medication is safe in pregnancy. Medication reconciliation before conception, not after a positive pregnancy test, gives time to switch to safer alternatives, taper drugs that require gradual discontinuation, or make informed decisions about risk-benefit ratios.

High-Priority Medications to Discuss

Several drug classes carry well-documented teratogenic risk:

• Isotretinoin (Accutane): Causes severe birth defects in nearly 25% of exposed fetuses. The FDA iPLEDGE program mandates two forms of contraception and monthly pregnancy tests during use. Women must discontinue and wait one month before attempting conception [17].
• Valproic acid (Depakote): Associated with neural tube defects in 1 to 2% of exposed fetuses and significant cognitive impairment. The FDA added a black box warning in 2013 specifically for use in women of childbearing potential [18].
• Warfarin (Coumadin): Causes warfarin embryopathy (nasal hypoplasia, stippled epiphyses) with first-trimester exposure. Low-molecular-weight heparin is typically substituted before conception in women who require anticoagulation [19].
• ACE inhibitors and ARBs: Contraindicated in pregnancy due to fetal renal toxicity and oligohydramnios. Women with hypertension should transition to pregnancy-compatible agents such as labetalol, nifedipine, or methyldopa before conception [20].
• Methotrexate: Used for rheumatoid arthritis, psoriasis, and ectopic pregnancy; causes fetal loss and major malformations. Discontinue at least three months before attempting conception [21].

Medications That Should Continue

Some medications must not be stopped abruptly. Anti-epileptic drugs, antidepressants, antihypertensives, and thyroid hormone replacement all have discontinuation risks that may outweigh embryonic exposure risks. The preconception visit is where these trade-offs are evaluated with a clinician, not where blanket discontinuation is advised [3].

Step 5: Modify Lifestyle Factors With Documented Reproductive Impact

Lifestyle modification before conception changes the reproductive outcomes data in ways that are measurable and reproducible across large trials.

Alcohol: No Safe Threshold

The CDC's position is unambiguous: there is no known safe amount of alcohol during pregnancy, and that recommendation extends to the period when a woman is trying to conceive, since conception timing cannot always be precisely predicted [22]. Fetal alcohol spectrum disorders (FASD) affect an estimated 1 in 20 school-age children in the United States according to a 2018 CDC study [22]. Abstinence before conception removes any exposure during the critical first weeks of organ formation.

Smoking and Tobacco

Smoking reduces fertility in both men and women and is independently associated with miscarriage, placenta previa, preterm birth, and sudden infant death syndrome (SIDS) [23]. Women who smoke 10 or more cigarettes per day have a miscarriage rate approximately 1.8 times higher than non-smokers in prospective cohort data [23]. Varenicline (Chantix) and bupropion (Wellbutrin) are the most effective pharmacological aids for cessation; both should be discontinued before conception, making the preconception period the right time to complete a cessation course [24].

Weight and Metabolic Status

A BMI of 30 or above at conception is associated with a three-fold increase in gestational diabetes risk, higher rates of cesarean delivery, and increased risk of neural tube defects independent of folate intake [25]. The HAPO study (N=23,316) demonstrated a continuous, graded relationship between maternal glucose levels and adverse perinatal outcomes, reinforcing that even modest improvements in glycemic control before pregnancy reduce risk [26].

Intentional weight loss before conception, achieved through caloric deficit and physical activity, improves both fertility and pregnancy outcomes. GLP-1 receptor agonists such as semaglutide (Ozempic, Wegovy) are currently contraindicated in pregnancy; women using these agents should discontinue at least two months before attempting conception based on the FDA label and limited human safety data [27].

Physical Activity

The American Heart Association recommends 150 minutes per week of moderate-intensity aerobic activity as a baseline for cardiovascular health [28]. This same threshold applies in the preconception period. Regular exercise before conception is associated with reduced gestational diabetes risk, better mood regulation, and easier maintenance of healthy gestational weight gain [28].

Caffeine

The CARE study (N=1,207) found that caffeine intake above 200 mg per day during pregnancy was associated with fetal growth restriction [29]. The American College of Obstetricians and Gynecologists advises limiting caffeine to less than 200 mg per day during pregnancy, and many clinicians apply the same threshold before conception as a precautionary measure [30].

Step 6: Address Mental Health Before Conception

Anxiety and depression are the most common medical complications of the perinatal period, affecting an estimated 15 to 20% of pregnant and postpartum women [31]. Starting care before conception rather than after delivery produces better outcomes for both mother and child.

Depression, Anxiety, and Pregnancy Outcomes

Untreated major depressive disorder during pregnancy is associated with preterm birth, low birth weight, reduced prenatal care utilization, and higher rates of postpartum depression [32]. A 2020 meta-analysis in JAMA Psychiatry (N=19,685) found that antenatal depression was associated with a 37% increased risk of preterm birth compared with non-depressed controls [32].

Medication Decisions for Mental Health

Selective serotonin reuptake inhibitors (SSRIs) are the most widely used class of antidepressants in pregnancy. Sertraline and escitalopram have the most reassuring reproductive safety data and are generally considered compatible with pregnancy when the clinical benefit outweighs risk [33]. Paroxetine carries a class D designation due to a small absolute increase in cardiac septal defects observed in some, though not all, epidemiological studies [33].

The preconception period is the right time to stabilize a psychiatric condition, not to abruptly discontinue medications that have been working. Uncontrolled psychiatric illness during pregnancy carries its own fetal risks [31].

Stress and Cortisol

Chronic psychological stress elevates cortisol and is associated with longer time to conception, irregular ovulatory cycles, and higher rates of early pregnancy loss [34]. Cognitive behavioral therapy (CBT), mindfulness-based stress reduction (MBSR), and structured social support have all demonstrated measurable reductions in perceived stress in preconception populations in randomized trial data [34].

The 3-Month Preconception Timeline: A Practical Framework

Most of the six steps above do not require months of effort individually, but coordinating them takes planning. Here is a practical sequencing guide:

12 months before: Achieve or approach goal weight if BMI is above 30. Complete a smoking cessation program. Stabilize any chronic condition (autoimmune disease, diabetes, thyroid disease). Review psychiatric medications with a prescriber.

3 to 6 months before: Schedule the formal preconception visit. Order labs (TSH, HbA1c, 25-OH-D, CBC, ferritin, rubella/varicella titers, STI panel). Begin 400 to 800 mcg of folic acid and a prenatal vitamin containing 150 mcg iodine and DHA. Switch teratogenic medications to safer alternatives. Discontinue GLP-1 agonists if applicable.

1 to 3 months before: Confirm rubella and varicella immunity (vaccinate if needed; wait one month after MMR before conceiving). Recheck TSH if on levothyroxine. Finalize alcohol cessation. Limit caffeine to <200 mg daily. Begin tracking the menstrual cycle to estimate ovulation timing.