A prospective, two-way open cohort design will be used when samples are collected and retrospective for analysis once the pregnancy is confirmed during follow-up.
Volunteer women who meet the inclusion and exclusion criteria, seeking a profile of a woman with a high probability of spontaneous pregnancy (age between 18 and 35 years, without pathologies, with regular menstrual cycles, with a normal body mass index ), will be grouped as women seeking pregnancy from the study group (EG) and women from the negative control groups (GCN) who will undergo clinical and ultrasound follow-up along with the taking of different biological samples both in the pre-phase -conceptional as during pregnancy and delivery as appropriate.
These samples correspond to cervicovaginal fluid (collected through a menstrual cup), saliva, blood, and urine.
The samples will be collected by the recruitment and collection team and will be stored at -80º C for later use in proteomics and genomics research.
The following graph shows the sampling scheme, which begins on day -6 of ovulation, this is predicted according to the analysis of previous cycles; until day 14 post ovulation, which is determined by hormonal analysis and ultrasound follicular monitoring.