Zika virus fears have left pregnant women with serious questions about how to avoid contracting the virus, and whether the use of insect repellents will put their fetuses at risk. Zika isn’t the only disease that’s bug borne (ticks also carry diseases such as Lymes and Rocky Mountain Spotted Fever) so avoiding these types of insect borne diseases depends upon the use of chemicals that deter bites. The first line a defense is avoiding areas that are affected by Zika, but the CDC has suggested that the virus will spread within the US, so the use of repellants is recommended for all pregnant women.

The most effective mosquito (and tick) repellent contains DEET, and it's considered safe to use during pregnancy and breastfeeding by the EPA. An alternative repellent is Picaridan, but that and other newer repellent chemicals haven’t been as rigorously tested for safety during pregnancy.  In studies that compared the effectiveness of 20% DEET, picaridin, IR3535 and plant based repellents such as citronella, cedar, lemon or eucalyptus, the DEET product was the most effective against the Aedes species mosquito that carries Zika.

Here are some tips for the best protection from mosquito bites:

• Most people notice mosquitos are more prevalent during early morning and dusk, but keep in mind that the mosquito that spreads Zika is more active during they day.  Make a habit of applying insect repellent every time you are going to spend time outdoors.
• Clothing can provide a barrier from bites, so when possible wear long sleeves and pants, and socks. Permethrin coated clothing provides the highest level of protection, but be sure to avoid spraying that products directly on your skin. The EPA has not seen any adverse fetal developmental issues associated with pregnant women wearing permethrin coated clothing when used as directed.
• Make sure that your home window screens aren’t torn or open in any areas.
• Some repellents decrease the SPF (duration of protection) of sunscreens, so for best sun protection apply an SPF 30 lotion or higher before applying insect spray, and reapply your sunscreen frequently when outdoors.
•  Use products that contain at least 20% DEET, which provide up to four hours of protection.  A 20-30% DEET product provides protection from 90% of mosquito or tick bites.

During pregnancy, the benefits of using DEET to avoid the Zika virus and serious birth defects for the fetus are far out weigh the concerns.  For the best protection and safety when using these products remember to carefully read all repellent instructions and apply as directed. 
For more information on the use of DEET and other products during pregnancy go to:

Organization of Teratology Information Specialists OTIS www.mothertobaby.org