The nausea has lifted — and now comes the anatomy scan, gestational diabetes screening, the question of birth preparation, and the physical demands of a growing pregnancy. Dr. Neha Sain takes you through weeks 13 to 40, covering the tests that matter, the symptoms to watch for, and how to prepare for birth in the Indian context.
For most women, the second trimester brings genuine relief. The nausea of the first trimester — which for many was the most exhausting and miserable part of the experience so far — begins to ease. Energy improves. The pregnancy becomes visible. And sometime around week 18 to 22, there is the flutter of movement — the baby's first felt kicks — which makes the whole thing feel undeniably real in a way that even the ultrasound images did not quite manage.
But the second and third trimesters are not simply a comfortable waiting period. They contain several important tests, meaningful clinical risks, physical changes that deserve proper management, and — eventually — the preparation for birth. Let me take you through what to expect.
The Second Trimester: Weeks 13 to 26
The Anatomy Scan: Weeks 18 to 22
This is one of the most important antenatal assessments of the entire pregnancy. The detailed anomaly scan — performed by ultrasound — systematically examines the baby's brain, face, heart, spine, abdominal wall, kidneys, limbs, and placenta. It also assesses amniotic fluid volume and placental position.
The scan cannot detect every possible condition — its sensitivity depends on the position of the baby, the quality of the equipment, and the experience of the sonographer — but it does identify the majority of major structural abnormalities. These include neural tube defects, cardiac abnormalities, cleft lip and palate, abdominal wall defects, and skeletal abnormalities.
Do not skip this scan. If the report comes back with any finding that needs follow-up, do not panic — many anomalies found at this stage are mild, resolve, or are false positives. Ask your doctor to explain the finding specifically and what, if anything, it means for management.
The scan will also check placental position. A low-lying placenta at this stage is common and usually migrates upward as the uterus grows. If it remains low (placenta praevia) at a later scan, it affects how and where you can safely deliver.
Gestational Diabetes Screening
India has one of the highest rates of gestational diabetes mellitus (GDM) in the world, reflecting our population's genetic predisposition to insulin resistance. The DIPSI (Diabetes in Pregnancy Study Group India) recommends universal screening at the first antenatal visit and a repeat test between 24 and 28 weeks.
The second-trimester test involves a 75g non-fasting oral glucose load, with a plasma glucose measurement at two hours. A result of 140 mg/dL or above is diagnostic of GDM.
GDM without management carries real risks: large-for-gestational-age babies (macrosomia), complicated deliveries, and a significantly elevated lifetime risk of type 2 diabetes for the mother. Managed well — through dietary modification, blood glucose monitoring, and when necessary, insulin — outcomes for both mother and baby are excellent.
Anaemia Check-In
Iron supplementation is recommended throughout pregnancy in India, given our high background prevalence of deficiency. Haemoglobin should be rechecked at 28 weeks. A level below 10.5 g/dL in the second trimester warrants medical review and possibly intravenous iron if oral supplementation has been insufficient.
Physical Changes in the Second Trimester
Round ligament pain: As the uterus expands, the round ligaments that support it are stretched. This causes sharp, stabbing pain on one or both sides of the lower abdomen — often precipitated by sudden movements, rolling over in bed, or laughing. It is harmless but often frightening when first experienced.
Backache: The growing uterus shifts the centre of gravity forward and places increasing strain on the lumbar spine and sacroiliac joints. Prenatal yoga, swimming, and physiotherapy-guided core strengthening are effective.
The Third Trimester: Weeks 27 to 40
Pre-eclampsia Monitoring
Pre-eclampsia — hypertension with proteinuria arising after 20 weeks — is one of the most serious pregnancy complications. It affects approximately 5–8% of pregnancies globally, with higher rates in India, and it is a leading cause of maternal and perinatal mortality in our context.
Blood pressure should be monitored at every antenatal visit. If you develop headache that does not respond to paracetamol, visual disturbances, significant swelling of the face and hands, or pain under the right rib cage — especially in the third trimester — contact your doctor urgently. Do not wait for your next appointment.
Fetal Movement Monitoring
From around week 24 onwards, you should feel regular fetal movements every day. There is no fixed number of kicks to count — rather, you should know your baby's individual pattern and be alert to any sustained reduction. If you notice your baby is moving significantly less than normal on any single day — contact your maternity unit. Do not wait overnight.
Reduced fetal movement can sometimes be the first sign of placental insufficiency or fetal compromise, and it always warrants assessment, not watchful waiting at home.
Preparations for Birth
From around 34 to 36 weeks, it is appropriate to have an informed, unhurried conversation with your obstetrician about your birth plan: where you will deliver, whether induction or caesarean is anticipated based on your specific clinical picture, and what your preferences are.
In India, caesarean section rates have increased sharply — the NFHS-5 data found a national C-section rate of 21.5%, with rates above 40% in some private hospital settings. A caesarean is sometimes the safest option for clinical reasons; it is also sometimes performed without a clear indication. Understanding your specific clinical situation — why a particular mode of delivery is being recommended and whether there are alternatives — is your right as a patient.
Warning Signs to Act on Immediately
Seek urgent assessment at any point in the third trimester for: heavy vaginal bleeding, severe abdominal pain, reduced or absent fetal movement, leaking fluid, symptoms of pre-eclampsia, or regular painful contractions before 37 weeks.
If you would like a personalised review of your antenatal care, test results, or birth preparation, you are welcome to submit a Smart Consultation. I will review your specific history and provide a clear response within 48 hours.
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