This study is based on pubertal surveillance of fetal ovarian cysts (KOF). Fetal ovarian cysts (KOF) detected during fetal ultrasound examinations occur during the 3rd trimester of pregnancy and are of unknown cause.

These cysts are functional in the vast majority of cases and are therefore likely to disappear spontaneously, but they may become complicated before regressing. Apart from complication, the natural evolution of these cysts, which are said to be "simple" because they are liquid on ultrasound, is towards regression in the first months of neo-natal life.

Surveillance during the 1st year of life showed that simple cysts regressed during the 1st trimester. In the case of complicated cysts, oophorectomy was necessary in 9 cases. In the 1-year follow-up, the ovarian recovery rate was significantly different depending on the appearance of the cyst (p<0.0001); 60 ovaries out of 89 homolateral to the cyst were follicular, of which 48/49 (98%) were carriers of fluid cysts and 12/40 (30%) were initially heterogeneous. The origin of these cysts is unknown, the ovary is again physiologically stimulated during the onset of puberty. No series in the literature gives the long-term ovarian prognosis for these patients. We wish to evaluate the pubertal evolutionary profile of patients followed at the University Hospital for KOF. The data collected concerning puberty (age of menses) will be examined in relation to the age of menses in the siblings and in the mother, as well as to the data in the literature on the age of the first menses in France.

Inclusion Criteria:

• Patients at least 8 years of age at the time of inclusion.
• Patients being followed for fetal ovarian cyst.
• Minor patients of whom at least one of the two holders of parental authority has given his or her non-opposition.
• Patients covered by a social security scheme.

Exclusion Criteria:

• Patients less than 8 years of age at the time of inclusion
• Ovarian cysts outside the neonatal period
• Refusal to participate.
• Opposition to disclosure of neonatal data.
• Pregnant or nursing patient.

Young girls who have to answer a questionnaire on their pubertal development. Estimated duration of data collection by questionnaire for one participant: 30 minutes maximum.