At latest update no published data on excretion into breastmilk were found.

 Because of a large volume of distribution along with a very low or undetectable plasma concentration reached after inhalation (Laurikainen 1988, Wood 1995), it must be very unlikely the passage of significant amounts into breastmilk.
Its low oral bioavailability would hamper the pass to the infant’s plasma through the breastmilk ingested.
It has been used to treat newborns (Pediamecum 2015). 

Experts and scientific societies consider the use of ipratropium bromide during breastfeeding as devoid of risk to the infant (van Haren 1998, National Asthma Education 2004, Amir 2011).