We Need to Improve Prenatal Screening Practices in Primary Obstetric Care: A Representative Data from a Fetal Medicine Unit in Coastal Karnataka.

Background: The present observational data from the fetal medicine unit aim to identify gaps in prenatal screening modalities employed in the primary obstetric care population in coastal Karnataka.

Methods: A retrospective observational study of all referrals to Fetal Medicine unit is over 2 years. For each fetal abnormality, we reviewed the literature to note the range of gestational age at which the abnormality should almost always be diagnosed. Taking this as standard, the gestational age at which each of these problems was diagnosed and referred was noted down. They were compared and analysed to understand the efficiency of prenatal screening practices in the referral population. The final perinatal outcome was also noted down in order to assess the impact on perinatal mortality/morbidity.

Results: A total of 277 cases were referred to fetal medicine unit. Two hundred twenty-eight cases (82.31%) were low risk pregnancies. Among 277 cases, 200 (72.2%) had structural abnormalities, 7 (2.5%) chromosomal/ genetic abnormalities, 61 (22.02%) isolated soft markers, and 9 (3.2%) twin-related problems. Detection rate of structural abnormalities was 33% at 14 weeks and 52.22% at 20 weeks, considering those anomalies usually diagnosed by these gestational age windows. The primary reason for delayed diagnosis was non-performance of ultrasound "on time", rather than missed diagnosis. Fifty-three per cent (106 out of 200) of all the fetal structural abnormalities were diagnosed beyond 20 weeks. Average gestational age at mid-trimester anomaly scan in this group was between 20 and 24 weeks. Sixty-one patients were referred due to isolated soft markers, 30 beyond 20 weeks. Eighty per cent of them did not have any aneuploidy screening in pregnancy.

Conclusion: Practice of fetal medicine hugely depends upon appropriate prenatal screening practices in the referral population. There is an urgent need to bring in standard protocols for Prenatal Screening across all the primary obstetric care providers, both in the public and private sectors. Considering the huge burden of delayed prenatal diagnosis in our country, the proposed revision of MTP bill is a welcome change in fast-growing field of fetal diagnosis and therapy.