A major issue for female scientists wanting to start a family is the career break--and the gap in their track record--that usually comes with having children. But the challenges women face when balancing career and family start well before the arrival of their first child. As pregnant scientists adjust to their changing life and body, they must also try to adapt their work and working environment to their new condition.
Above all, women must keep safe and healthy throughout their pregnancy, and working in a research lab doesn’t make that easy. The issue is the same no matter what country you're in, but different parts of the world have strikingly different ways of dealing with the issue. In Europe, employers are required by law  to conduct a risk assessment once a woman has informed them, often in writing, of her pregnancy. To the eyes of European authorities, a lab contains many more risks than those posed solely by physical, chemical, and biological agents. Mental and physical fatigue, standing or sitting for too long, and stress at work are all recognised as potential threats  during pregnancy. Once risks are identified, employers must guarantee that they are avoided, and this may go all the way to forbidding a woman to access research labs--even if it puts her scientific career on hold.
In the United States, on the other hand, academic institutions have few policy guidelines that protect pregnant women from exposure to potential threats other than radiation. Women are often left to assess on their own whether their work in the lab is dangerous for them and their fetuses. To make things more difficult, many substances are more harmful in the early stages of pregnancy, when the woman may not be aware that she is pregnant. The reassuring note is that according to some studies, lab workers in general are at no increased risk of problems during pregnancy. These studies, however, are widely viewed as inadequate, and specific hazards are known to exist in the lab.
Health and safety issues need to be taken seriously, but pregnant scientists have to deal with many others. Women often delay announcing their pregnancy to their supervisor out of fear that they would miss out on the opportunity to go to an important conference, gain some research training abroad, or get more funding or a new position. Women may also worry about their colleagues assuming that their new condition makes them less committed to their work, and that this may affect their working relationships.
Staying in the lab can be difficult, but leaving the lab may be even more difficult. Women scientists should find out as early as possible whether it is possible to extend the period of their funding and get paid maternity leave, and before leaving, they should negotiate the conditions of their return. The impact of a career break will be smallest if women manage to get that paper published before they leave, arrange to attend a conference while on maternity leave, and organise their research projects so that it is easy to get back in the swing of things when they return. Carefully arranged, even a generous maternity leave need not seem longer than the unproductive--pun intended--spells that most researchers experience from time to time.
The challenges for pregnant scientists often come unannounced and need to be dealt with quickly. The stakes are high. Most women will have children at one point or another in their career, yet pregnancy and the lab is not a typical topic for conversations in most departmental tearooms. So where should you turn for the information you need? We took the initiative, talking to health and safety officers, principal investigators, and young scientists to find out more about the issues, provide some answers, and pass on some firsthand experiences.
The Top Five Challenges for Pregnant Scientists 
From keeping safe and healthy to interacting with your colleagues, the challenges that come along with pregnancy are many and often unforeseeable. Freelancer Lynn Dicks  offers scientists from Europe and other parts of the world a guide on how to handle them.
Alone in the Lab 
Jim Kling  looks at the health and safety issue from a North American perspective. The good news is that lab workers are at roughly the same risk of pregnancy problems as the general population. But the bad news is that most U.S. institutions lack guidelines for pregnant lab workers, leaving women to identify hazards and solutions on their own.
Managing Your Career Through a Pregnancy 
North and West Europe Editor Anne Forde  talks to young scientists around Europe about what it's like to be an expectant mother in the lab and about the impact of their pregnancy on their life and work.
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