Like all ideas that become social imperatives, the "breast is best" mandate of recent decades -- the assertion that breast-feeding is superior to the bottle -- isn't true for everyone. Director Dana Ben-Ari never argues the point in the documentary "Breastmilk," instead letting women's experiences speak for themselves.

The first-time filmmaker follows five New Yorkers, a cross section of ages and incomes, from late in their pregnancy through the first year of motherhood. She spikes their discerning, often anxiety-filled comments with provocative observations from experts and other parents, including same-sex couples.

The subject's appeal is decidedly limited, but the intimate chronicle is no one-note celebration of the goddess. Ben-Ari embraces real-life complexities and elemental questions about gender roles, mother-child bonding and female sexuality (lactation pornography gets a shout-out).

She reveals not just the sublime moment when a nursing newborn's gaze fixes on its mother's face, but how pressure to do the natural thing can give rise to new categories of maternal guilt and feelings of inadequacy. With a 2014 Ohio State study of siblings showing no significant long-term health advantages for breast-fed children by the time they reach ages 4 to 14, the orthodoxy surrounding breast-feeding might be loosening. Our "ridiculously competitive" supermom culture, as a health worker in the film describes it, is another matter.

There are "Portlandia"-worthy moments amid the talk of breast pumps, latching and engorgement, and also surprising insights with implications beyond the nursery. Playfully artsy close-ups of squirting nipples might be as off-putting to some viewers as the participants' earnest testimony will be to others. Either way, audiences will find themselves face to face with their own prejudices, assumptions and, perhaps, squeamishness.

'Breastmilk'

* * *

Rating: NR
Director: Dana Ben-Ari
Running time: 1 hour, 31 minutes