Holder et al (unpublished work 1979) found that in a series of 13 women who gave weekly samples of blood between weeks 6 & 14 from LMP with a final sample at 17 weeks from which serum hCG, βhCG, progesterone and oestrodiol were estimated. These values were related to the women’s symptoms of nausea and vomiting in the previous week that each sample of blood was taken (6). The correlations between maternal serum hCG levels and pregnancy sickness symptoms in individual patients were so limited that they were clearly insignificant, agreeing with the findings of Soules. However, when serum hCG levels of those women with severe symptoms were compared with those with mild symptoms, raised hCG and bhCG levels were significantly associated with severe symptoms during weeks 7 and 9-12 from first day of last menstrual period (LMP), agreeing with the findings of Kaupilla, Masson and Jarnfelt Samsioe. In addition, when the overall maternal serum hCG levels were compared with overall sickness symptoms for several weeks throughout early pregnancy, there was a correlation for maternal serum hCG (P<0.02) and bhCG (P<0.01) levels with sickness symptoms from weeks 6-11 from LMP. This association became highly significant when bhCG and hCG serum levels and sickness symptoms were compared for weeks 6-17 from LMP (P<0.001). At the same stage of pregnancy the fall of serum progesterone during weeks 5-9 from LMP and its subsequent rise to week 17 showed an inverse association with the rise of pregnancy sickness symptoms in weeks 5-9 and fall of these symptoms from weeks 10-17 from LMP. Table 1 (6).. La hormona Beta hCG es fabricada por el cuerpo pocos días después de la concepción y su evolución es uno de los indicadores de una correcta progresión del embarazo.. maternal serum human chorionic gonadotrophin (hcg) βhcg and progesterone levels in weeks 5-17 from lmp associated with symptoms of pregnancy sickness Clinical relationship between maternal serum hCG and pregnancy sickness..