The present invention concerns compositions comprising and methods of identification and use of targeting peptides for placenta or adipose tissue. In certain embodiments, the targeting peptides comprise part or all of SEQ ID NO:5-11, SEQ ID NO:13-22 OR SEQ ID NO:144. The peptides may be attached to various therapeutic agents for targeted delivery. Adipose-targeting peptides may be used in methods for weight control, inducing weight loss and treating lipodystrophy syndrome. Adipose-targeting may also be accomplished using other binding moieties selectively targeted to adipose receptors, such as a prohibitin receptor protein complex. Placenta-targeting peptides may be used to interfere with pregnancy, induce labor and/or for targeted delivery of therapeutic agents to placenta and/or fetus. In other embodiments, receptors identified by binding to placenta-targeting peptides may be used to screen compounds for potential teratogenicity. An exemplary placental receptor is FcRn/.beta..sub.2M, and compounds that bind to FcRn/.beta..sub.2M are potential teratogens.