No increased risk of peanut allergy with antenatal intake or intake during breast feeding, or with infant intake (Fox, J Allergy Clin Immunol. 2009 Feb;123(2):417-23). But did find dose response with household intake, esp peanut butter – so avoid!?

10 000 mums in US, not high risk, Eating Peanuts/Tree Nuts ≥5 times vs <1 time per month in their peripregnancy diet reduced risk of allergy by 2/3: odds ratio = 0.31; 95% CI, 0.13-0.75; Ptrend = .004). [Lindsay Frazier JAMA Pediatr. 2014;168(2):156-162. doi:10.1001/jamapediatrics.2013.4139]

60 000 mums in Danish National Birth Cohort, those eating peanuts and treenuts at least once weekly had kids with less asthma (OR 0.66), tree nuts also appeared to protect against rhinitis.

1200 US mums (not high risk) Higher maternal peanut intake (each additional z score) during the first trimester was associated with 47% reduced odds of peanut allergic reaction (odds ratio [OR], 0.53; 95% CI, 0.30-0.94).[J Allergy Clin Imm Volume 133, Issue 5, May 2014, Pages 1373–1382. DOI: 10.1016/j.jaci.2013.11.040]