How to calculate the formula of giving birth to boys and girls in Runnian?

49+4 (lunar month of conception refers to the day before and after ovulation) -33 (pregnant age, nominal age)+19=39 (male)

To put it bluntly, this formula is a wish. The formula is definitely not that rigorous. The situation of leap month is really bad. According to the truth, it should still be April. Actually, it has nothing to do with 49 You are an imaginary odd number. You are a girl one month pregnant and a boy two months pregnant. It should be noted that your pregnancy in April is not necessarily your ovulation in April. If you ovulate in March, you have to count it in March. Because no matter how to calculate, there is a 50% correct rate. If you do it right, you will feel extremely right. Actually, there is no science at all.