What substances and activities should a pregnant individual avoid to minimize complications and ensure a healthy pregnancy?

What to Avoid During Pregnancy

Pregnant individuals must completely avoid alcohol, tobacco, illicit drugs, certain medications (especially NSAIDs after 20 weeks), specific teratogenic agents, high-risk physical activities, excessive heat exposure, and scuba diving to prevent maternal and fetal complications.

Substances to Completely Avoid

Alcohol and Illicit Drugs

• Alcohol consumption must be completely avoided throughout pregnancy and during breastfeeding, as it increases the risk of SIDS and causes fetal harm 1.
• All illicit drugs including marijuana and methamphetamine must be discontinued immediately upon pregnancy recognition 2.
• The combination of alcohol or illicit drug use with any activity (including bed-sharing with infants postpartum) places infants at particularly high risk 1.

Tobacco

• Smoking must be stopped immediately using the "five A's" approach (Ask, Advise, Assess, Assist, Arrange) for smoking cessation 1.
• Both prenatal and postnatal tobacco exposure increase SIDS risk 1.
• Psychosocial and behavioral interventions should be utilized, with pharmacotherapy considered when benefits outweigh risks 2.

Medications Requiring Avoidance or Extreme Caution

NSAIDs (including ibuprofen):

• Avoid NSAIDs completely after 30 weeks gestation due to risk of premature closure of the fetal ductus arteriosus 3.
• Limit use between 20-30 weeks gestation to lowest effective dose and shortest duration (ideally <48 hours) due to risk of oligohydramnios and neonatal renal impairment 3.
• If treatment extends beyond 48 hours after 20 weeks, ultrasound monitoring for oligohydramnios is required 3.

Category X and Most Category D Medications:

• Avoid FDA pregnancy category X medications entirely (e.g., isotretinoin/Accutane) 1.
• Avoid most category D medications unless potential maternal benefits clearly outweigh fetal risks 1.
• Specific teratogens to avoid include warfarin (Coumadin) and certain antiseizure medications 1.

Over-the-Counter Products:

• Review all over-the-counter medications, herbs, and supplements with an obstetric provider 1.
• Avoid hibiscus tea and consider beverages with established safety profiles instead 4.

Physical Activities and Environmental Exposures to Avoid

High-Risk Physical Activities

• Never scuba dive during pregnancy, as the fetus is not protected from decompression sickness and gas embolism 1.
• Avoid activities involving physical contact or danger of falling, including horseback riding, downhill skiing, ice hockey, gymnastics, and Olympic lifts 1.
• Avoid non-stationary cycling due to higher fall risk; substitute with stationary cycling, brisk walking, swimming, or aquafit 1.

Heat and Altitude Exposure

• Avoid physical activity in excessive heat, especially with high humidity, to prevent maternal hyperthermia 1, 5.
• Avoid hot yoga due to dehydration risk 5.
• If using a hot tub, limit exposure to less than 10 minutes with water temperature below 39.0°C, and exit immediately if feeling unwell 5.
• Lowlander women (living below 2500m) should avoid physical activity at high altitude (>2500m) 1.

Workplace and Environmental Toxins

• Avoid exposure to teratogenic agents including heavy metals, solvents, pesticides, endocrine disruptors, and allergens at home, in the neighborhood, and workplace 1.
• Review Material Safety Data Sheets for workplace exposures and consult a teratology information specialist when needed 1.

Specific Positioning and Sleep Safety

Exercise Positioning

• Modify physical activity to avoid the supine position when feeling unwell, though this recommendation is based on limited evidence 1.
• Maintain the "talk test" during exercise—reduce intensity if unable to maintain a conversation 1.

Postpartum Infant Sleep Safety (Relevant for Pregnancy Planning)

• Avoid bed-sharing with infants, particularly when the infant is younger than 3 months 1.
• Never bed-share if you are a smoker, excessively tired, or using medications/substances that impair alertness 1.
• Keep soft objects, loose bedding, pillows, quilts, and bumper pads out of the infant's sleep environment 1.

Infections to Prevent

• Take precautions to prevent TORCH infections (Toxoplasmosis, Other viruses, Rubella, Cytomegalovirus, Herpes simplex) 1.
• Screen for and treat periodontal, urogenital, and sexually transmitted infections as indicated 1.

Warning Signs Requiring Immediate Medical Attention

Stop all physical activity and seek immediate medical care if experiencing:

• Persistent excessive shortness of breath that does not resolve with rest 1.
• Severe chest pain 1.
• Regular and painful uterine contractions 1.
• Vaginal bleeding 1.
• Persistent loss of fluid from the vagina indicating rupture of membranes 1.
• Persistent dizziness or faintness that does not resolve with rest 1.

Common Pitfalls to Avoid

• Do not assume "natural" products are safe—herbs and supplements require the same scrutiny as medications 1.
• Do not discontinue needed chronic disease medications without consulting an obstetric provider, as untreated conditions (e.g., asthma, epilepsy, hypertension) can be more dangerous than medication risks 1.
• Do not rely solely on internet information—conflicting recommendations are common and should be verified with healthcare providers 6.
• Avoid douching and always wear seatbelts 1.