This was easier than expending undue effort* to go look up my birth certificate.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3219436/
In the United States, mean birth weight increased during the second half of the 20th century, continuing through the 1990s.1–4 Similar trends occurred in Canada,5–7 the United Kingdom,8–10 Scandinavia,11–13 and Japan.14 More recently, U.S. national surveillance data suggest that this upward trend in mean birth weight is reversing.15
We used data from the U.S. National Center for Health Statistics for 36,827,828 singleton neonates born at 37–41 weeks of gestation, 1990–2005. We examined trends in birth weight, birth weight for gestational age, large and small for gestational age, and gestational length in the overall population and in a low-risk subgroup defined by maternal age, race or ethnicity, education, marital status, smoking, gestational weight gain, delivery route, and obstetric care characteristics.
In 2005, compared with 1990, we observed decreases in birth weight (−52 g in the overall population, −79 g in a homogenous low-risk subgroup) and large for gestational age birth (−1.4% overall, −2.2% in the homogenous subgroup) that were steeper after 1999 and persisted in regression analyses adjusted for maternal and neonate characteristics, gestational length, cesarean delivery, and induction of labor. Decreases in mean gestational length (−0.34 weeks overall) were similar regardless of route of delivery or induction of labor.
*i.e. putting down my drink and getting off my ass