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

Abstract

Summary: Objective: In the Czech Republic, it is possible, to carry out Medical Termination of Pregnancy (MToP) in the 1st trimester up until the 49^th 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 < 0.0001) and crown-rump length of the embryo – CRL (R = 0.605; P < 0.0001). Gestational age was 42–49 days (average 45.6, median 45 days), the women were 16–44 years of age (average 29.4, median 29 years). In MToP follow-up, serum hCG level was > 1,000 IU/L in 13.8% of women (15/109) and a positive LSUP test in 17.4% (20/109). US examination diagnosed ongoing pregnancy in five women and missed abortion in one woman (serum hCG was always > 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.