RESUMEN
OBJECTIVE: To compare ß-hCG levels measured as the first pregnancy test in women who conceived after in vitro maturation (IVM) or IVF. DESIGN: Retrospective matched cohort analysis. SETTING: University-based medical center. PATIENT(S): Women treated with IVM or IVF. INTERVENTION(S): We studied the first serum ß-hCG levels in 104 pregnant women who were successfully treated with IVM and in another 104 women with IVF treatment. Blood samplings for ß-hCG were drawn on day 12-15 after ET. The two groups were matched by age, order of pregnancy, and day of blood sampling. MAIN OUTCOME MEASURE(S): First ß-hCG levels. RESULT(S): Serum ß-hCG levels on days 12 to 13 after ET of IVM viable singleton pregnancies were significantly higher than those of IVF pregnancies (343.2±48.4 vs. 264.0±29.2 IU/L, 95% confidence interval [CI] 22-229). Similarly, ß-hCG levels on days 14 to 15 after ET of IVM viable singleton pregnancies were higher than those of IVF pregnancies (350.1±126.4 vs. 284.4±30.2 IU/L). Similar trends were found in ß-hCG levels on days 12 to 13 after ET of twin viable pregnancies (IVM, 682.1±97.7 vs. IVF, 434.5±41.8 IU/L; 95% CI 44-662). Grouped linear regression with covariance analysis showed a significant difference between IVM and IVF regression lines. CONCLUSION(S): The first serum ß-hCG levels in pregnancies after IVM are consistently higher than those after IVF treatment. More studies are needed to elucidate these findings.