The mutual fusion of the male semen and female menstrual secretion inside the female womb is called conception. That is fusion of mixture intake received by the female is called conception.[43] The birth of a creature acquiring a body through mother's menstrual secretion and father's semen is called conception.[44]
Kinds of ConceptionsConception results into four kinds of foetus - female, male, neuter and a solid mass of flesh.[45] Excess of semen produces male, excess of female secretion produces female, both being equal results into neuter and if the female secretion freezes due to defective humours it results into a mass of flesh.[46] Manusmṛti,[47] Caraka Saṁhitā,[48] Aṣtānga haṛdaya[49] and Suśruta Saṁhitā confirm this opinion. Manusmṛti gives one more reason for this that if a ovulating woman has intercourse on even nights she gives birth to a male child while if she conceives on odd nights she produces a female child. Explaining it more scientifically Bhoja says that during even nights the quality of menstrual secretion is less while on odd nights its quality is more and therefore, the said results.[50]
In the book Bahula Vaicārika Prakīrṇaka this topic is discussed focusing on the situation of the embryo too. The embryo situated in the right side of the womb grows into a male child, the one situated in the left side grows to be a female child while the embryo situated in the middle of the uterus grows to be an eunuch.[51] The same is discussed in detail in Suśruta.[52] Some western scholars also have maintained that there exists such substances in the right ovary of woman that possesses the power to produce a male child while the left ovary produces a female child.[53]
Modern scientists explain that birth of a male or female child is determined by sperm cell. XY chromosomes determine the male sex while XX chromosomes are responsible for female sex. Egg cell contains XX chromosome where as sperm cell has XY chromosomes. When the X chromosome from mother and Y chromosome from father fuse together, a boy is born, whereas if both of them contribute only X chromosomes, a girl child is born.[54] If at the time of conception, the male breaths from right nostrils and the female breaths from left nostril, a male child is born.[55] According to Japanese scientists a pregnant lady can convert her foetus into either male or female through her will power. If from the time of conceiving till two months, she auto suggest herself repeatedly before going to sleep that "I will give birth to a son" she may bear a son. He claims nearly 200 women have given birth to male children in this way.[56] Similarly, a western scientist conducted experiments on lower animals ascertaining sex of the young ones and concluded that a rich diet results into female sex while a poor diet produces male sex. He believes the same will prove successful for women too.[57]
In the opinion of well known Philosopher Aristotle if, at the time of conception, there blows a northerly wind, the embryo grows to be a male child. There are numerous such beliefs but many of them are not logical enough, therefore, they are not discussed here.