Kisspeptins are a family of neuropeptides that are critical for the puberty initiation and female fertility. The investigators aimed to investigate in this study kisspeptin levels in early pregnancy, ectopic pregnancy, and early pregnancy loss.

Clinicians can easily do a differential diagnosis of early pregnancy, miscarriage, and ectopic pregnancy when the human chorionic gonadotropin (hCG) values higher than 2000 mIU/mL with transvaginal ultrasound. However, in cases where the hCG value is below the critical threshold of 1500 to 2000 mIU/mL (often called the discrimination level) and ultrasound is not likely to be diagnostic, the pregnancy is of unknown location. Plasma or serum kisspeptin is mainly derived from the placenta during pregnancy and plasma kisspeptin levels significantly increase across pregnancy. Plasma kisspeptin levels could be used as a potential biomarker for the discrimination of miscarriage and ectopic pregnancy. All statistics will be carried out with the use of SPSS (ver. 21, IBM). A P value of \<.05 is considered to be statistically significant. Pearson chi-square test will be used to evaluate between-group differences by pregnancy outcome for categoric data. Kisspeptin differences will be calculated between groups with one way ANOVA.