Brief Answer:
Follow as per the treating Gynecologist recommendations.

Detailed Answer:

Hello,

Well, 28 week means you're already in your third trimester of pregnancy. If all previous tests were fine and the fetal anomaly scan is already carried out, then additionally, you should continue with routine Fetal heart rate monitoring (can be done once / twice weekly or even more frequent based on the pregnancy status and as per the treating gynecologist).

Additionally, your gynecologist may also order a check sonogram, and few other tests to rule out any sexually transmitted infections (i.e. syphilis, gonorrhea, HIV, chlamydia) and Group B Streptococcus screening and a few more/less based on your clinical history.

This is a sensitive phase of pregnancy, and the decision of investigations may vary in each and every individual differently. Please follow the treating gynecologist's advice and always discuss with him / her in case of any doubts.

Take care.
Regards

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