Doll, Kitten and Brynn, from Massachusetts, were joined together in a marriage-style ceremony last August and are expecting a daughter in July.
Kitten, 27, is pregnant after undergoing IVF treatment using an anonymous sperm donor, and the trio eventually plan to have three children – one for each of them.
The plan at the moment is that Kitten will bear all the children – possibly using her wives’ eggs and donated sperm – but they are open to other options, such as adoption.
Brynn, 34, says: ‘The hope is to have three kids altogether. We always joke that the children should never outnumber the parents.’
Doll, Kitten and Brynn Young married in a ceremony in August 2013, when each of their fathers walked them down the aisle. All three women wore white wedding gowns and exchanged rings.