怀上孩子/双胞胎(等等)
to be pregnant
  I hear his wife's having a baby. 我听说他妻子怀孕了。 
 She was delighted to discover that she was having a baby.
 When they got married, everyone assumed she was having a baby.
 The technician asked if I knew I was having twins.
 When she found out she was having triplets, she didn't know whether to laugh or cry.
 See also: have verb (BABY)