Hormonal profiles of early gestations with abnormal karyotype.

OBJECTIVE

To describe the hormonal profiles of chromosomally abnormal pregnancies during the first trimester.

DESIGN

A prospective study from 1984 through 1990 in which infertility patients who conceived were monitored weekly with serum E2, P, and beta-hCG levels.

SETTING

The infertility practice at Rush-Presbyterian-St. Luke's Medical Center in Chicago, Illinois.

PATIENTS

Study included 15 women who had dilatation and curettage for first trimester fetal losses with confirmed abnormal karyotype, 6 women with chromosomally normal male abortuses, and 60 consecutive women whose pregnancies yielded normal term infants.

RESULTS

After natural conception, E2 demonstrated a moderate rise in both normal and chromosomally abnormal pregnancies to approximately 300 pg/mL by day 29 (6 weeks of gestation). In normal gestations, E2 continued a steady increase to exceed the level of 1,000 pg/mL by day 64 (11 weeks of gestation). In chromosomally abnormal pregnancies, the mean E2 plateaued and remained at approximately 200 pg/mL until fetal demise was noted. In stimulated conceptions, the rise of E2 was sharp and early (1,200 pg/mL by day 29); in normal pregnancies, E2 steadily increased to an average of 1,400 pg/mL by the end of the first trimester, whereas in karyotypically abnormal gestations, E2 declined to approximately 200 pg/mL by day 64. In pregnancies yielding a male abortus, a sharp decline and plateau at 800 pg/mL by day 56 (10 weeks of gestation) was observed. In both natural and stimulated normal pregnancies, hCG levels first demonstrated a linear rise, followed by a curvilinear increase from day 29 until day 56, with a peak of approximately 110,000 mIU/mL. The beta-hCG in chromosomally abnormal pregnancies, as well as in pregnancies yielding a male abortus, was characterized by a slow and gradual rise to a maximum of 40,000 mIU/mL, which remained relatively linear until day 64 when fetal demise was detected in all cases. Progesterone level data were excluded from analysis because of frequent P supplementation.

CONCLUSIONS

There were significant differences in the hormonal profiles of chromosomally normal and abnormal pregnancies. Serial measurements of serum E2 and beta-hCG from the 6th week of gestation may be useful in predicting an abnormal karyotype sooner than other current diagnostic tests.