LMP
LMP stands for last menstrual period, meaning the first day of your most recent period before you became pregnant. Doctors use this date to estimate how far along your pregnancy is, because the exact date of ovulation and conception is often unknown. Pregnancy is counted as 40 weeks starting from the LMP, even though conception typically happens around week two. If your cycles are irregular or longer than 28 days, the LMP-based estimate may be inaccurate. In that case, an early ultrasound scan, usually done between 8 and 12 weeks, gives a more reliable dating of your pregnancy.
What This Means for You
Understanding LMP is an important part of your early pregnancy journey. During pregnancy, your care team will use this term regularly. Being familiar with it means you can ask better questions and feel more confident at your antenatal appointments.
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At your first antenatal visit in Singapore, your doctor or midwife will ask for your LMP date, so it helps to note it in a period-tracking app before you conceive. If you are unsure of the date, a dating ultrasound at KKH or NUH can establish your gestational age more accurately.
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Always consult your healthcare provider for personalised advice.
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