ISRO do recruit doctors but there are no such specialization requirements like Gyno or else. Although you have to keep an eye on the notifications of recruitment released by ISRO. To know about the notifications for vacancy you visit the link below:

https://www.isro.gov.in/careers

The answer is yeah! ISRO recruits doctors and medical officers so you can go for it.

You can check the notification of 2016 for ISRO Medical Officer recruitment:

https://www.isro.gov.in/sites/default/files/iprc_advt-new.pdf

The eligibility is:

MBBS from a recognised University registered with Medical Council of India (candidates possessing grades below II class need not apply) 2 Years Experience in a reputed hospital Permanent registration from Medical Council of India.

I hope this answer helps. All the very best for your future endeavors!