1. Hyperemesis during pregnancy and delivery outcome: a registry study;Kallen;Eur J Obstet Gynecol Reprod Biol,1987
2. Hyperemesis gravidarum;Abell,1992
3. Epidemiology of vomiting in early pregnancy;Klebanoff;Obstet Gynecol,1985
4. Nausea and vomiting of early pregnancy and pregnancy outcome: an epidemiological study;Weigel;Br J Obstet Gynaecol,1989
5. Nausea and vomiting of early pregnancy and pregnancy outcome;Weigel,1989