To identify whether potential components of the pro-inflammatory environment associated with obesity can drive acute BRCA1 upregulation in the first trimester placenta, human chorionic villous explants (gestational week 5+0–10+4, n = 6–11) were incubated with TNF-α (50 ng/mL), leptin (100 ng/mL), and interleukin 6 (IL-6) (100 ng/mL) for 48 h. Here, BRCA1 is linked to obesity due to melanocortin 4 receptor deficiency.