Shah Rukh Khan is a Bollywood legend and a household name across the sub-continent.
Media reports suggest he and his wife are expecting a baby boy - to be born by a surrogate.
Health authorities have launched an inquiry to find out whether the couple used an ultrasound test to determine the baby's gender.
Such tests are banned in India because of the high rate of female infanticide.
Presenter: South Asia Correspondent Michael Edwards
Speakers: Shah Rukh Khan, Bollywood actor; Dr Ranjana Kumari, Centre for Social Research in New Delhi
(Audio from Shah Rukh Khan song)
MICHAEL EDWARDS: If could imagine combining the star power of Brad Pitt, Tom Cruise, Tom Hanks and Bruce Springsteen, then you're getting close to understanding Shah Rukh Khan's popularity across the Subcontinent.
The Indian actor has starred in hundreds of movies, his songs are hits, and he endorses almost every product imaginable.
(Song from Pepsi ad)
MICHAEL EDWARDS: And unlike many men in Bollywood who flaunt their hedonistic values, he's also a respected family man with two children.
He spoke recently of encouraging his daughter Suhana to follow him into the entertainment industry.
SHAH RUKH KHAN: I would like her to be part of the film industry, because I really believe - I'd be very proud if my daughter as an actress.
I'd be very, very proud for every aspect, whether it's a song, whether it's a dance, whether it's the cover shoots of fashion magazines, whether it's the interviews - whether it's whatever.
MICHAEL EDWARDS: But the actor now finds himself amid controversy surrounding an alleged ultrasound he and his wife Gauri are said to have used to work out the sex of their unborn child. They're said to be using a surrogate.
Reports suggest the baby is a boy, but such testing is illegal in India.
Women's rights activists estimate hundreds of thousands of baby girls are aborted each year and India's gender balance is heavily distorted towards boys.
The ratio is 914 girls born to every 1,000 boys.
Dr Ranjana Kumari is from the Centre for Social Research in New Delhi.
RANJANA KUMARI: It is a very serious issue, because even in 2011 census, the zero to six age group - which is infants - the sex ratio has gone down. We have still a lot of issues in terms of people getting sex selections done followed by abortion, and female foetuses are being aborted around 7,000 according to UNICEF report, on a daily basis.
MICHAEL EDWARDS: Shah Rukh Khan and Gauri have so far even refused to even confirm whether or not they're actually having a third child.
But Indian health authorities are taking the claims of a gender test seriously.
Health officials in the state of Maharastra have launched an investigation.
The Indian Medical Association says gender-testing laws should be applied to everyone, regardless of their level of fame or fortune.
But according to Dr Ranjana Kumari, gender selection is mostly carried out by the educated and the wealthy.
RANJANA KUMARI: The ones who can take care of two children or three children, whatever they want, and also who can educate them well, who can look after them well, are the ones who are the ones who are doing this, because this really speaks volumes that education does not change your mindset.
And also in some sense they don't want to distribute the resources between the male and the female child, between their daughters and their sons.
They want to give it to their sons, and that perhaps is the only reason that one can understand and one can explain this whole thing.
MICHAEL EDWARDS: Dr Kumari says she really hopes the claims about Shah Rukh Khan are not true.
RANJANA KUMARI: I really fail to understand this whole phenomena, and I fail to understand why we are working so hard to reverse this whole trend, we are working so hard to protect girl children, and there's a huge (inaudible) campaign that we are doing in the country - the "my strength, my daughter" campaign - and here is this film star; he's an icon, he endorses products, he will market products, and now he's endorsing something which is totally unacceptable.
It's ridiculous what he has done, if he has done that.
MICHAEL EDWARDS: If the Khans are having a baby and do know its sex, it is possible they did the test overseas - in which case they will have no problems under Indian law.