Madam Qin's method was something Su Yunjin also knew, it was what people in the modern era called the "safe period," referring to having intercourse in the week after a woman's menstruation, when it's generally harder for a woman to get pregnant, though it's not absolute, just a lower probability, and not a certainty.
After saying this, Madam Qin intentionally scrutinized Su Yunjin with a curious expression. At first, Su Yunjin didn't think there was anything unusual in Madam Qin's words, but being looked at like this, she suddenly felt something was off.
"Madam Qin, you...?" Su Yunjin stared at Madam Qin, instinctively about to ask how Madam Qin knew about the safe period.
Su Yunjin learned about the safe period in modern times, could it be that there was also such a concept in ancient times? With a face full of suspicion, Su Yunjin looked at Madam Qin, who casually asked, "Su sister, why? Is there anything wrong with what I just said?"
