A healthy pregnancy starts with the choices you make — before conception, throughout each trimester, and in the weeks after delivery. The guidance in this article is grounded in recommendations from the American College of Obstetricians and Gynecologists (ACOG), the World Health Organization (WHO), the CDC, and the NIH. Always confirm specific decisions with your own healthcare provider, as individual circumstances vary.

Before pregnancy: prepare your body

The months before conception are one of the most impactful windows for improving pregnancy outcomes. ACOG recommends that anyone planning a pregnancy take steps to optimize their health before conceiving, including reviewing all current medications with a provider — some common medications (including certain acne treatments, blood pressure drugs, and anticoagulants) are unsafe in pregnancy and require switching to alternatives before conception.

• Review all medications with your doctor — confirm which are safe during pregnancy and arrange alternatives if needed.
• Control blood pressure — chronic hypertension increases the risk of preeclampsia and preterm birth; bring it into a healthy range before conceiving.
• Manage blood sugar — elevated blood glucose before and during early pregnancy is associated with increased risk of birth defects, particularly cardiac and neural tube defects.
• Stop smoking immediately — there is no safe level of tobacco exposure in pregnancy; smoking is linked to preterm birth, placental abruption, low birth weight, and SIDS.
• Stop alcohol and substance use — fetal alcohol spectrum disorders are entirely preventable; there is no established safe level of alcohol during pregnancy.
• Reach a healthy weight — both underweight and overweight status before pregnancy are associated with increased complication rates; gradual, sustainable changes are preferable to rapid weight loss before conception.

Prenatal vitamins and folic acid

Prenatal vitamins are not a supplement to a poor diet — they are a targeted nutritional insurance policy against specific deficiencies that are common even in well-nourished pregnant people, because the demands of fetal development exceed what diet alone typically provides. The most critical window for folic acid supplementation is before the neural tube closes, which occurs by week 6 of pregnancy — often before a person even knows they are pregnant.

Key nutrients in prenatal vitamins and why they matter:

When to start: Begin prenatal vitamins 1–3 months before trying to conceive. If pregnancy is unplanned, start as soon as you know you are pregnant. Continue through breastfeeding.

Exercise during pregnancy

ACOG recommends that pregnant people with uncomplicated pregnancies aim for at least 150 minutes of moderate-intensity aerobic activity per week, spread across most days. This is consistent with the general adult exercise recommendation and is supported by extensive evidence linking regular prenatal exercise to reduced risk of gestational diabetes, preeclampsia, preterm birth, excessive gestational weight gain, and postpartum depression.

Safe and recommended activities:

• Walking, swimming, water aerobics
• Stationary cycling
• Prenatal yoga and Pilates
• Low-impact aerobics and dance
• Strength training with moderate weights (with technique modifications as pregnancy progresses)

Activities to avoid or modify:

• Exercises lying flat on your back after the first trimester — this position compresses the vena cava (a major vein) and can reduce blood flow to the uterus
• Contact sports with risk of abdominal impact (soccer, basketball, martial arts)
• Activities with high fall risk (skiing, horseback riding, gymnastics)
• Scuba diving — fetal tissue cannot filter decompression bubbles
• Hot yoga or exercise in excessive heat — core temperature elevation above 102°F (39°C) poses neural tube risks in early pregnancy

Stop exercising and contact your provider if you experience: chest pain, difficulty breathing before exertion, painful uterine contractions, vaginal bleeding, dizziness, or calf pain and swelling.

Staying hydrated

Blood volume increases by approximately 40–50% during pregnancy to sustain the placenta and deliver oxygen and nutrients to the growing fetus. This dramatically increases fluid requirements. The NIH recommends at least 8–10 cups (64–80 oz) of water daily during pregnancy, with higher needs during hot weather or exercise.

Adequate hydration during pregnancy helps:

• Prevent constipation and hemorrhoids (common in pregnancy due to progesterone slowing digestion)
• Reduce urinary tract infection risk — more common during pregnancy due to hormonal changes
• Alleviate headaches and fatigue, both of which are frequently dehydration-related
• Reduce swelling (edema) — counterintuitively, adequate hydration helps kidneys eliminate excess fluid
• Regulate amniotic fluid levels

Water, milk, and diluted 100% fruit juice count toward daily fluid intake. Limit sugary drinks and caffeinated beverages. Herbal teas should be cleared with your provider, as some have uterine-stimulating effects.

Nutrition: what to eat and what to avoid

The 2020–2025 US Dietary Guidelines for Americans include, for the first time, specific recommendations tailored to pregnant individuals. The core principle is nutrient density — meeting increased caloric and micronutrient needs without excessive weight gain. Starting in the second trimester, an additional 340 calories per day is recommended (increasing to 450 in the third trimester).

Foods to prioritize

• Folate-rich foods: dark leafy greens (spinach, kale), asparagus, lentils, beans, fortified cereals and bread, oranges and orange juice, broccoli, strawberries
• Calcium-rich foods: dairy products, fortified plant milks, tofu made with calcium sulfate, sardines and canned salmon (with bones), kale, bok choy
• Iron-rich foods: lean red meat, poultry, fish, beans, lentils, fortified cereals, tofu — pair with vitamin C to enhance absorption
• High-fiber foods: whole-grain bread, oatmeal, brown rice, vegetables, fruits, beans — reduce constipation risk
• Low-mercury seafood: salmon, sardines, trout, shrimp, catfish, tilapia — excellent sources of DHA for fetal brain development. Aim for 8–12 oz per week
• Protein sources: lean meats, eggs, beans, lentils, nuts, seeds, and low-mercury fish

Foods and substances to avoid during pregnancy

• High-mercury fish: swordfish, shark, king mackerel, tilefish, bigeye tuna — limit all fish to 12 oz per week
• Raw or undercooked meat, poultry, eggs, and seafood — risk of Salmonella, E. coli, Listeria, and Toxoplasma
• Unpasteurized soft cheeses (Brie, Camembert, feta, queso fresco) — Listeria risk
• Raw sprouts — Salmonella and E. coli risk
• Deli meats and hot dogs unless heated to steaming — Listeria risk
• Unpasteurized juices and dairy
• Caffeine above 200mg/day (roughly 12oz of coffee) — linked to increased miscarriage risk at higher levels
• Alcohol — no safe level established; fetal alcohol spectrum disorders are entirely preventable

Substances and chemicals to avoid

Beyond food, several environmental exposures carry documented fetal risks:

• Tobacco in all forms — cigarettes, vaping, smokeless tobacco, and secondhand smoke are all harmful; smoking is associated with placental abruption, preterm birth, SIDS, and developmental delays
• Alcohol — causes fetal alcohol spectrum disorder (FASD), a leading preventable cause of intellectual disability
• Illicit drugs and marijuana — associated with low birth weight, developmental issues, and SIDS risk; discuss all substance use with your provider honestly and without judgment
• Organic solvents — paint thinners, nail polish remover, and certain cleaning agents; minimize exposure when painting a nursery by ensuring strong ventilation and limiting time in freshly painted rooms
• Pesticides — wash all produce thoroughly; avoid applying pesticides or herbicides yourself during pregnancy
• X-rays and certain medical tests — always inform healthcare providers of your pregnancy or potential pregnancy before diagnostic imaging or procedures

Physical tasks to reassign during pregnancy: heavy lifting, climbing ladders or step stools, prolonged standing, and changing cat litter (risk of Toxoplasma gondii transmission).

Sleep and stress management

Pregnancy significantly disrupts sleep — especially in the third trimester when physical discomfort, frequent urination, and anxiety about birth combine to reduce sleep quality. ACOG and sleep medicine guidelines recommend aiming for 8–10 hours of sleep per night during pregnancy, supplemented by daytime naps when nighttime sleep is poor.

Sleep positions: sleeping on your left side is recommended from mid-pregnancy onward — it optimizes blood flow to the placenta and kidneys by avoiding compression of the inferior vena cava. A pregnancy pillow supporting the belly, back, and between the knees significantly improves comfort in the third trimester.

Evidence-based stress reduction strategies:

• Prenatal yoga — well-studied for reducing cortisol levels, improving sleep, and reducing labor anxiety; look for classes specifically designed for pregnancy
• Mindfulness meditation — apps such as Headspace and Calm have pregnancy-specific programs; even 10 minutes daily shows measurable stress hormone reduction in research settings
• Deep breathing exercises — diaphragmatic breathing activates the parasympathetic nervous system and is also useful as a labor coping tool
• Prenatal massage — seek certified prenatal massage therapists; regular massage has been shown to reduce cortisol, improve sleep, and decrease labor complications in some studies
• Social support — strong social support networks are independently associated with better pregnancy and postpartum outcomes in research literature

Warning signs: when to call your doctor

It can be difficult to distinguish normal pregnancy discomfort from warning signs that require prompt medical attention — especially for first-time parents. When in doubt, contact your provider. The following symptoms always warrant a call:

Postpartum care

The postpartum period — sometimes called the "fourth trimester" — carries its own significant health risks that are frequently underestimated. Medical complications including postpartum preeclampsia, infection, blood clots, and hemorrhage can occur days to weeks after delivery, even after an apparently uncomplicated birth. The traditional six-week postpartum visit is a minimum, not the ceiling; anyone who experienced pregnancy complications, high blood pressure, or preterm labor should follow up much sooner.

Postpartum physical health

• Postpartum preeclampsia — high blood pressure can develop or worsen after delivery; seek immediate care for severe headache, vision changes, or swelling in the days to weeks after birth
• Wound care — cesarean incisions and perineal tears require monitoring for signs of infection (redness, warmth, discharge, fever)
• Blood clots — pregnancy and the postpartum period dramatically increase clot risk; seek immediate care for leg pain, swelling, or difficulty breathing
• Continue prenatal vitamins through breastfeeding — nutritional demands remain elevated while nursing

Postpartum mental health

Up to 20% of new mothers experience postpartum depression (PPD) — a clinical condition, not a character flaw or sign of inadequate parenting. PPD goes well beyond the "baby blues" (mild mood changes in the first 2 weeks) and can develop at any point in the first year after birth. Risk factors include prior depression history, insufficient social support, birth complications, and breastfeeding difficulties.

Contact your provider if you experience persistent (more than 2 weeks) feelings of sadness, hopelessness, inability to bond with your baby, intrusive thoughts, inability to sleep when the baby sleeps, extreme anxiety, or thoughts of harming yourself or your baby. Effective treatments include therapy, medication, and peer support groups — and most are compatible with breastfeeding.