Brief Answer: Hi Detailed Answer: the answer is not so simple. Puberty is a period( that starts in girls between 9-13 years) and this is not just one moment. So girls cant know did their puberty(sexual puberty) start, until they get first menstruation. And first menstruation occurs 15 days after first ovulation. If there was fertilization during this first ovulation,then girl will be pregnant without having first menstruation; this is of course very rare and there is very small chance that there was intercourse right during first ovulation ever. Secondly. first periods are usually irregular so sometimes girls cant determine did periods start or not. Also,other features of puberty such as hair grow, fat tissue accumulation ,genital development are not very specific in determining female fertility. All in all, if girl didnt have period yet,then pregnancy is possible but chances are almost negligible. There are cases where first ovualtion was first fertilization too,but as I said this is rare scenario.

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Brief Answer: Hi Detailed Answer: Yes,we can say it almost like that.There is no pregnancy before puberty. But there are reported few cases in human history in extreme precocious puberty where girls had child in those ages that you mentioned so the youngest one was 5 years old. But there are only several reported such cases. of course, it is not natural for girls to have sex in this age so the Nature didnt give them pregnancy potentional.

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Brief Answer: Hi Detailed Answer: Yes,it is impossible if there is no ovulation since there is no female egg then. First period usually occurs between 11 and 14 and rarely below age 9. But as I mentioned it is not impossible that it happens even in 6 or 7 years old girl,but this is considered to be hormonal disorder.

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Brief Answer: Hi Detailed Answer: Yes,thats right. It is practically impossible for ovulation to occur before 5 and almost never it occurs between 5-8, while only 5% of girls get ovulation before the age 10.

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