As an employee you have a duty to take reasonable care of your own safety and health at work. As soon as a female employee knows she is pregnant she should tell her employer and doctor. This is a good opportunity to discuss with both her doctor and employer whether the work she does may affect her pregnancy or whether her pregnancy may restrict the type of work she does. If there are any potential problems then these can be discussed with her employer at the earliest opportunity. 

As pregnancy progresses widespread changes occur in most systems of a woman’s body so as to provide a suitable environment for the growing foetus. Some of these physiological changes may affect a woman?s working capacity; important examples are: 

• Circulatory changes: there are increases in blood volume and the amount of blood pumped by the heart (cardiac output). This reduces the heart's ability to adapt to exertion and also increases pressure in the veins in the legs, which makes standing for long periods difficult and uncomfortable. Pregnant women often find that they cannot tolerate hot weather very well, especially in the later stages of pregnancy, and this may be a problem if a woman is also working hard. 
• Body weight: women gain weight during pregnancy, some more than others, most noticeably during the last 6 months. Some of this weight gain is due to an increase in body fluids and fat deposits, and the rest is from the growing foetus. Consequently, this extra load has to be added on to an employee's usual work load and may increase feelings of fatigue. 
• Nutrition: the body's running costs increase during pregnancy to meet the needs of the foetus and also the mother's extra weight. The energy requirements during pregnancy are equivalent to the requirements of two to four hours of work. 
• Ligaments: changes in hormone levels in the body cause ligaments to become more easily stretched, especially later in pregnancy, and this may make the back (and other joints) more vulnerable to injury when lifting heavy weights (or participating in some sporting activities). 
• Posture: the extra weight and bulk in the abdominal region leads to an exaggeration of the normal low back curve (lumbar lordosis). This will make some tasks more difficult, especially when standing or carrying loads, if it is necessary to reach forward or above the shoulders to reach a load, or even sitting in one position for long periods. Poor posture may also contribute to the backache experienced by many pregnant women. 

Current medical opinion is that moderate exercise is good for pregnant women and a lot depends on the woman's state of health and level of fitness before she became pregnant. Paid work (which may be a necessity during pregnancy) is different from voluntary exercise, in that an employee has a responsibility to her herself, her employer and fellow employees. 

A review of tasks undertaken to identify potentially hazardous manual tasks, as well as any other hazards (such as the presence of chemicals which may be hazardous to pregnant women), needs to be done. Risk assessments of those work tasks that have been identified as a hazard when undertaken by a pregnant employee should be performed. The key lies in gaining a full understanding of those work situations where the employee may be at risk of injury to herself or her unborn child. 

Any previous risk assessments that have been made for these tasks will need to be reviewed  as the situation has changed because there is now a pregnant employee to consider. Once the risk assessment has been completed then appropriate risk control measures should be implemented. 

Some potential risk factors related to manual tasks during pregnancy are: 

• fatigue due to physiological changes in conjunction with an excessively long work week; 
• prolonged standing (for more than 3 hours per day); 
• heavy physical workload (continuous or periodical physical effort, carrying loads of more than 10 kg); 
• working under hot working conditions if a lot of sweat is being produced; and 
• frequent forward bending, stooping or reaching above shoulder height, even when light loads are being handled. 

Some practicable control measures that can be implemented include: 

• reviewing the work tasks undertaken to avoid heavy work duties, in particular avoidance of extremely heavy physical exertion in early pregnancy and a reduction of the physical workload after the third month and again after the sixth month of pregnancy; 
• reducing, if possible, the amount of time spent working under hot conditions, or improving workplace climate or ventilation, especially if heavy work is involved; 
• reviewing work tasks that require a lot of bending and reaching, especially late in pregnancy, in order to reduce as much as possible the range of movements required; 
• provision of rest breaks during the day; and 
• establishing a more flexible work system, for example: changing the pattern of work through alteration of shift work and reduction in overtime.