Work Environment Restrictions During Pregnancy: Temperature and Safety Guidelines
Pregnant women should avoid physical activity in excessive heat, especially with high humidity, as this can pose risks to both maternal and fetal health. 1
Temperature Guidelines
Ambient Temperature Recommendations
- Optimal workplace temperature range: 20°C to 22°C (68°F to 71.6°F) is considered comfortable for pregnant women 1
- Humidity considerations: Humidity should be maintained below 60% as cardiovascular responses become variable above this level 1
- Delivery room temperature:
Heat Exposure Limits
- Pregnant women can safely engage in:
Critical Temperature Thresholds
- Maternal core temperature: Should remain below 39.0°C to avoid teratogenic risk 3
- Neonatal temperature: Should be maintained between 36.5°C and 37.5°C after birth 1, 2
Physical Activity Restrictions
Safety Precautions
- Avoid activities involving physical contact or danger of falling 1
- Avoid non-stationary cycling due to higher risk of falling 1
- Avoid scuba diving as the fetus is not protected from decompression sickness 1
- Avoid physical activity at high altitude (>2500m) unless under medical supervision 1
Contraindicated Activities
- Horseback riding
- Downhill skiing
- Ice hockey
- Gymnastics
- Olympic lifts 1
Warning Signs to Stop Activity
Pregnant women should stop activity and seek medical attention if experiencing:
- Persistent excessive shortness of breath that doesn't resolve with rest
- Severe chest pain
- Regular and painful uterine contractions
- Vaginal bleeding
- Persistent loss of fluid from the vagina
- Persistent dizziness or faintness that doesn't resolve with rest 1
Occupational Considerations
High-Risk Work Environments
- Heat-exposed workplaces: Women working in environments exceeding threshold limit values (maximum wet-bulb globe temperatures of 27.5°C for heavy workload and 28.0°C for moderate workload) have doubled risk of adverse pregnancy outcomes 4
- Heavy physical work: Women engaged in moderate to heavy physical work in hot environments show increased risk of:
- Miscarriage (adjusted odds ratio 2.4)
- Adverse pregnancy and fetal outcomes (adjusted odds ratio 2.3)
- Adverse outcomes at birth (adjusted odds ratio 2.0) 4
Monitoring Recommendations
- Monitor core body temperature during strenuous work in hot environments
- Check for signs of dehydration (urine specific gravity ≥1.020 indicates moderate dehydration) 4
- Use the "talk test" during physical activity - if unable to maintain conversation, reduce intensity 1
Preventive Measures
Environmental Controls
- Use circulating fans to assist in controlling room temperature and ventilation 1
- Maintain a cool, dry environment (50% humidity) to enhance heat dissipation 1
- Consider workplace modifications for pregnant women in hot environments 4
Personal Measures
- Maintain adequate nutrition and hydration—drink water before, during, and after physical activity 1
- Include warm-up and cool-down periods in any physical activity regimen 1
- Consider water-based exercise as it provides greater heat loss 5
Special Considerations
First Trimester
- Heat exposure is most hazardous during the first trimester of pregnancy 5
- Women may not be aware of their pregnancy during this critical period, so workplace temperature policies should account for this 5
Preterm Infants
- Preterm infants are more vulnerable to hypothermia and may require more aggressive warming measures 2
- Use combination of interventions including radiant warmer, plastic wrap, warm blankets, cap, and thermal mattress 2
By following these guidelines, pregnant women can maintain safe working conditions that protect both maternal and fetal health while allowing continued productivity in the workplace.