Medical Termination of Pregnancy (MToP) in the 1st trimester - the role of human chorionic gonadotropin and ultrasound in pregnancy diagnosis and MToP follow-up.

Objective: In the Czech Republic, it is possible, to carry out Medical Termination of Pregnancy (MToP) in the 1st trimester up until the 49th day of secondary amenorrhea. The aim of the study is to analyse the significance of serum/urine human chorionic gonadotropin (hCG) assessment and ultrasound (US) examination in pregnancy diagnosis and MToP follow-up.

Methods: In 2017-2018, MToP was carried out in a total of 109 women by administering a combination of mifepristone (600 mg orally) and misoprostol (400 mcg orally). Serum/urine (LSUP - low sensitivity urine pregnancy test) hCG assessment and US examination were performed at pregnancy diagnosis and MToP follow-up.

Results: At pregnancy diagnosis, there was a positive and medium strong correlation between serum hCG and size of the gestational sac - GS (R = 0.711; P  1,000 IU/L and LSUP test was always positive). In 5.5% of women (6/109), a subsequent surgical intervention was carried out including those with ongoing pregnancy (N = 5); missed abortion (N = 1) was treated by additional misoprostol, where surgical intervention was not necessary.

Conclusion: At pregnancy diagnosis, there is a positive and medium strong correlation between serum hCG and CRL. In MToP follow-up, a negative LSUP test enables reliable exclusion of ongoing pregnancy and missed abortion. In case of a positive LSUP test, US examination should be performed; however, surgical intervention should not be indicated solely on the basis of uterine cavity dilatation.