Is microwaving food in plastic safe during pregnancy?

What does the evidence say about microwaving food in plastic during pregnancy?

1. Microwave ovens heat food with non-ionising radiation and do not make food radioactive or contaminated, and ovens meeting the FDA standard and used per the manufacturer's instructions are considered safe to use. 1
2. Some plastic containers should not be used in a microwave because they can be melted by the heat of the food inside, and the FDA advises using cookware specifically manufactured for microwave use. 1
3. NIEHS advises not microwaving polycarbonate plastic food containers, since polycarbonate may break down over time from repeated use at high temperatures, and notes that some plastics marked with recycle codes 3 or 7 may be made with BPA. 2
4. How much BPA leaches from a polycarbonate bottle into liquid depends more on the temperature of the liquid or the bottle than on the age of the container, and NIEHS suggests glass, porcelain, or stainless steel particularly for hot food or liquids. 2
5. Testing of plastic containers during microwave operations detected dibutylphthalate migrating into food simulants at up to 7.5 micrograms per litre, with higher temperature increasing migration and containers used for a prolonged time releasing more as heating time went up. 3

Is microwaving food in plastic safe in each trimester?

• First trimester. Microwaves use non-ionising radiation, so there is no radiation concern for a first-trimester pregnancy from standing near one. What the research actually flags is migration from the container, and swapping to a glass bowl solves that in one move.
• Second trimester. Retire the tired containers. Phthalate migration testing showed little pattern in new containers, but a clear rise in ones that had been used for a long time, and the increase tracked with heating time. Warped, cloudy, or scratched tubs are the ones to replace.
• Third trimester. Takeaway and meal-prep containers matter most late in pregnancy, when reheating gets more frequent. Yoghurt tubs, margarine containers, and delivery boxes were never designed for the microwave. Plate the food first, and let hot leftovers cool a little before sealing them in plastic.