Abnormal uterine bleeding during puberty: to the pathogenesis and diagnosis
Authors: Kovalishin O.A. 
Published: August 2022

The objective: to study the genetic aspects of the pathogenesis of abnormal uterine bleeding during puberty (AUB PP) and to evaluate the effectiveness of diagnostic measures taking into account the presence or absence of mutations in the MTHFR C677T gene.Materials and methods. Sixty girls with a history of AUB PP were included in the main group and 30 healthy girls without AUB consisted the control group. The main group is divided into three subgroups: the 1st subgroup (n=20) – the girls with AUB PP, born from the mothers with physiological pregnancy; the 2d subgroup 2 (n=20) – the girls with AUB PP, born form the mothers whose pregnancy was complicated by preeclampsia; the 3d subgroup (n=20) – the girls with AUB PP, born from the mothers with a history of miscarriage.All persons were examined with the study of reproductive and menstrual functions, the assessment of hormonal status, family and hereditary anamnesis, ultrasound examination of the pelvic organs in the dynamics of the menstrual cycle. Depending on the duration of bleeding and the severity of compensatory disorders, the severity of anemia the mutations in the MTHFR C677T gene and homocysteine ​​concentration were determined in girls and their mothers in the blood, the assessment of menstrual blood clotting and morphological status of the endometrium were performed.Results. The mothers of girls with AUB PP had pregnancy complications significantly more often (reccurent miscarriages – 28.0 %, preeclampsia - 25.8 %) than mothers of healthy girls (14.0 % and 12.2 %, respectively), in 55,0 % of cases a mutation in the MTHFR C677T gene was detected, which is absent in mothers of healthy girls. The majority of girls with AUB PP born from the mothers with a history of miscarriage (70.0 %) or preeclampsia (60.0 %) was 7 and 6 times more likely to have mutations in the MTHFR C677T gene, respectively, than girls with AUB PP who were born from the mothers with physiological pregnancies without complications (10.0 %). Mutation of the MTHFR C677T gene was found in 3.3 % of healthy girls.Serum homocysteine ​​levels in girls and their mothers who had the MTHFR C677T gene mutation were 6.0±1.2 and 8.0±1.0 μmol/L, respectively, and did not differ significantly from those in girls and mothers without the mutation. The clinical picture and state of the hemostasis system in girls with AUB PP and the presence of mutations in the MTHFR C677T gene also did not differ significantly from the clinical picture of girls with AUB PP without this mutation and healthy girls. But in the menstrual blood of girls with AUB PP and mutations in the MTHFR C677T gene, hyperfibrinolysis was significantly more pronounced than in the menstrual blood of healthy girls and girls with AUB PP without gene mutations.Conclusions. The analysis of the presence of mutations in the MTHFR C677T gene in girls with AUB PP demonstrates that mutation in this gene is 6 times more often in patients who were born from the pregnancies complicated by preeclampsia, and 7 times more often in girls with AUB PP who were born from the mothers with pregnancy loss in the anamnesis, in comparison with those who were born from physiologically normal pregnancy.