What should I be mindful of in relation to pregnant workers? Is there a right to suspend?

Yes, but as a last resort. In summary, the law requires employers:

• to assess the workplace risks posed to new or expectant mothers or their babies;
• to alter the employee’s working conditions or hours of work to avoid any significant risk to them;
• where it is not reasonable to alter working conditions or hours, or would not avoid the risk, to offer suitable alternative work on terms that are not “substantially less favourable”;
• where suitable alternative work is not available, or the employee reasonably refuses it, the employer should consider whether it is appropriate to suspend the employee on full pay.