As others have said, it's now often expected that women who're TTC must act as though they could be pregnant.
I had comments when pregnant over alcohol, sex, caffeine, prawns, blue cheese, meat, going to smoky places, stress, wearing heels, going out in the evening, "doing too much", lying down too much (may lead to non-optimal position), commuting, driving, lifting my toddler, working til 37 weeks, exercising (both too much and not enough), our birth plan/wishes, how long we waited ( or didn't wait) before ttc after 30, birth or miscarriage, wearing underwired bras, taking a pessary for thrush, taking paracetomol, eating out, eating nuts, not eating enough veg, weight gain (too much / not enough).
Some of it must be about control.
Have also heard some really horrible comments about women who have had miscarriages, premature babies or stillbirth along the lines of "well she did X, Y or Z......." ( unfinished statements but clear woman-blaming).