Obstetric complications (OCs) are robust environmental correlates of schizophrenia (McNeil, 1988; Cannon, 1997). Deviations from the normal course of pregnancy, delivery, or early neonatal life have been associated with the development of schizophrenia in numerous studies with many different types of samples, including: adult schizophrenics and matched comparison subjects (O'Callaghan et al., 1992; Kendell, Juszczak, & Cole, 1996; Hultman, Ohman, Cnattingius, Wieselgren, & Lindstrom, 1997), siblings and twins discordant for schizophrenia (Lane & Albee, 1966; Pollack, Woerner, Goodman, & Greenberg, 1966; Pollin & Stabenau, 1968; Woerner, Pollack, & Klein, 1971; Markow & Gottesman, 1989; Eagles et al., 1990; Bracha, Torrey, Gottesman, Bigelow, & Cunniff, 1992; Günther-Genta, Bovet, & Hohlfeld, 1994; Kinney et al., 1994; Torrey et al., 1994), adopted schizophrenics (Jacobsen & Kinney, 1980), offspring of schizophrenic parents (Parnas et al., 1982; Fish, Marcus, Hans, Auerbach, & Perdue, 1992), and representative birth cohorts (Buka, Tsuang, & Lipsitt, 1993; Dalman, Allebeck, Cullberg, Grunewald, & Koster, 1999; Zornberg, Buka, & Tsuang, 2000). The two studies reporting null results are not outliers in this respect, only in that the 95 percent confidence intervals of their risk estimates included values of one (Done et al., 1991; Buka et al., 1993). One of these studies found that odds of schizophrenia were 2.6 times higher among individuals with a history of fetal hypoxia than among those without such a history (p = .13), but statistical power was limited by a small number of schizophrenia outcomes (N = 8; Buka et al., 1993).