Two short stanzas turn the body into a place where something is being born. The speaker imagines their heart as a "beautiful fat woman in childbed," heavy, tender and in the middle of labor or recovery, while the speaker becomes the bed that holds her. It's a strange, intimate picture: the speaker isn't the one giving birth but the one providing support, the thing that bears the weight.
The second stanza is trickier. The speaker says they "increase" in any place where they "want to live all in one place." That could mean the self grows, swells or multiplies wherever it feels at home, much like a pregnant body expanding. There's a tension in the wording, though: increasing suggests spreading out, while living "all in one place" suggests wholeness and settling down.
The mood is warm, odd and quietly playful. The title, "Reproductive system," adds a dry, clinical contrast to the soft, bodily imagery, so feeling and biology blur together.