Here is a thread on a few of the nutrition, food prep, and supplementation guidelines that I followed during my first pregnancy.

I ate salmon roe to support fetal brain development. DHA in phospholipid form accumulates in the fetal brain at 10x the rate compared to DHA in free fatty acid form. 40-70 percent of the DHA in roe is in phospholipid form (salmon meat contains just 1-3% by comparison).

Licorice consumption during pregnancy is linked to significant IQ reduction (up to 7 points). I avoided licorice candy, anise-flavored candy/beverages, and herbal teas containing licorice root (you may be surprised how many teas have licorice root in the ingredients).

Tylenol use during preg. can increase the risk of autism by 30%, is linked to language delays at up to 6x the frequency in girls, and can reduce testosterone production in developing testes by 45%. Of course, these studies are based on specific dosages, but I avoided altogether.

A high intake of acrylamide during pregnancy is linked to lower birth weight and smaller head circumference. I minimized starchy foods cooked at high temperatures (potato chips, French fries, breakfast cereal, toast, etc.). I also cut out coffee, which is rich in acrylamide.

I avoided foods/beverages high in arsenic, cadmium, and lead. I minimized rice (especially brown), chocolate, high-mercury fish, and tea grown in China (particularly problematic is tea made with mature leaves such as oolong and black).

High fluoride exposure during pregnancy is associated with reduced IQ. I filtered my city tap water with a Berkey fluoride filter (most home filter systems do not remove fluoride). I avoided fluoride toothpaste/mouthwash.

I cooked meat low and slow. I avoided grilled and smoked meats to minimize exposure to polycyclic aromatic hydrocarbons (PAHs). Increased exposure to PAHs is linked to lower birth weight and smaller head circumference.

I supplemented with Visbiome in my 3rd trimester, intending to improve my baby’s gut health and reduce her chance of colic.

Many of these recommendations are thanks to @foundmyfitness