Explanation:

 It is a subtler way of son preference which means that parents may choose to keep having children until they get the desired number of sons.
It does not lead to sex selective abortion but it may be detrimental to female children because it may lead to fewer resources devoted to them.
This form of sex selection alone will not skew the sex ratio.
This kind of fertility stopping rule will lead to skewed sex ratios but in different directions i.e. skewed in favor of males if it is the last child, but in favor of females if it is not.

A preference for sons will manifest itself in the SRLC being heavily skewed in favor of boys. For India, the sex ratio of the last child for firstborns is 1.82, heavily skewed in favor of boys compared with the ideal sex ratio of 1.05. This ratio drops to 1.55 for the second child for families that have exactly two children and so on. The striking contrast between the two panels conveys a sense of son meta preference. 

It gives rise to “unwanted” girls (girls whose parents wanted a boy, but instead had a girl), computed as the gap between the benchmark sex ratio and the actual sex ratio among families that do not stop fertility. It stands at 21 million for India. Reasons for such a son preference include patrilocality (women having to move to husbands’ houses after marriage), patrilineality (property passing on to sons rather than daughters), dowry (which leads to extra costs of having girls), oldage support from sons and rituals performed by sons.